1995 AGRICULTURAL RESEARCH

Transcription

1 1995 AGRICULTURAL RESEARCH Report of Progress 733 AgriculturI Experiment Sttion Knss Stte University, Mnhttn Mrc A. Johnson, Director SOUTHEAST AGRICULTURAL RESEARCH CENTER

2 LYLE LOMAS, Reserch Center Hed, received B.S. nd M.S. degrees in Animl Husbndry from the University of Missouri nd Ph.D. degree in Animl Husbndry from Michign Stte University. He provides ledership for reserch nd is responsible for Reserch Center dministrtion. Lyle joined the stff in 1979 s Animl Scientist. His reserch interests re beef cttle nutrition, production, nd mngement. KEN COFFEY, Animl Scientist, received B.S. degree in Animl Science from the University of Tennessee, M.S. degree in Animl Science from the University of Kentucky, nd Ph.D. degree in Animl Science from the University of Missouri. He joined the stff in His reserch focuses on ruminnt nutrition nd improving forge utiliztion by grzing beef cttle. KEN KELLEY, Crops nd Soils Agronomist, received B.S. degree in Agriculturl Eduction nd M.S. degree in Agronomy from Knss Stte University. He hs been stff member since His reserch includes evlution of herbicides, crop rottion systems, nd intensive whet mngement. JIM LONG, Crop Vriety Development Agronomist, received B.S. degree from Missouri Southern Stte College nd M.S. nd Ph.D. degrees in Agronomy from the University of Arknss. He joined the stff in 1990 nd directs vriety performnce testing of grins, works with plnt breeders in development nd evlution of new whet nd soyben cultivrs, nd conducts soyben production reserch. JOE MOYER, Forge pgronomist, received B.S., M.S., nd Ph.D. degrees in Agronomy from Knss Stte University. He hs been stff member since His reserch evlutes cultivrs nd mngement prctices with forge grsses nd legumes nd forge utiliztion by beef cttle. DAN SWEENEY, Soil nd Wter Mngement Agronomist, received B.S. degree in Chemistry from Kentucky Wesleyn College, M.S. degree in Agronomy from Purdue University, nd Ph.D. degree in Soil Science from the University of Florid. He joined the stff in His reserch focuses on soil fertility, tillge nd compction, nd irrigtion.

3 TABLE OF CONTENTS BEEF CATTLE RESEARCH EFFECT OF PREVIOUS SPRING STOCKING RATE ON FALL GRAZING AND SUBSEQUENT FEEDLOT PERFORMANCE OF STEERS... 1 EFFECT OF FEEDLOT IMPLANT PROGRAM ON PERFORMANCE BY STEERS PREVIOUSLY GRAZING INFECTED FESCUE PASTURES... 6 PERFORMANCE BY STEERS GRAZING INFECTED AND NONINFECTED FESCUE PASTURES WITH AND WITHOUT LADINO CLOVER OVERSEEDING... 9 PERFORMANCE BY STEERS GRAZING RYE/BERMUDAGRASS PASTURES WITH AND WITHOUT LADINO CLOVER OVERSEEDING PERFORMANCE BY FINISHING STEERS OFFERED MAGNESIUM-MICA IN THE FEEDLOT RATION EFFECT OF MAGNESIUM-MICA DURING GRAZING AND/OR FEEDLOT PHASES ON PERFORMANCE AND RUMEN FERMENTATION PRODUCTS OF STEERS. 20 EFFECTS OF YEAST AND SODIUM BICARBONATE ON RUMINAL DIGESTION AND INTAKE OF HIGH CONCENTRATE DIETS FORAGE CROPS RESEARCH ALFALFA VARIETY PERFORMANCE IN SOUTHEASTERN KANSAS FORAGE PRODUCTION OF BERMUDAGRASS CULTIVARS IN SOUTHEASTERN KANSAS LEGUME PERSISTENCE UNDER HAY PRODUCTION MANAGEMENT NITROGEN RATE AND PLACEMENT EFFECTS ON EASTERN GAMAGRASS UNDER 1-CUT AND 2-CUT HARVEST SYSTEMS SOIL AND WATER MANAGEMENT RESEARCH TILLAGE AND NITROGEN FERTILIZATION EFFECTS ON YIELDS IN A GRAIN SORGHUM - SOYBEAN ROTATION TIMING OF LIMITED-AMOUNT IRRIGATION TO IMPROVE YIELD AND QUALITY OF EARLY-MATURING SOYBEAN i

4 GRAIN SORGHUM RESPONSE TO LEGUME RESIDUAL AS AFFECTED BY PHOSPHORUS AND POTASSIUM LAND APPLICATION OF COMPOSTED MUNICIPAL SOLID WASTE FOR GRAIN SORGHUM PRODUCTION FOLIAR POTASSIUM THIOSULFATE AND BORON FERTILIZATION OF DRYLAND ALFALFA CROPS AND SOILS RESEARCH EFFECTS OF PLANTING DATE AND FOLIAR FUNGICIDE ON WINTER WHEAT WHEAT AND SOYBEAN ROTATIONS COMPARED LONG-TERM EFFECTS OF CROPPING SYSTEMS ON SOYBEAN YIELDS SOYBEAN HERBICIDE RESEARCH CROP VARIETY DEVELOPMENT RESEARCH SOYBEAN VARIETY TRIAL FOR CYST NEMATODE RESISTANCE PERFORMANCE TRIAL OF DOUBLE-CROP SOYBEAN VARIETIES VARIETY RESISTANCE AND ROTATIONS FOR SOYBEAN CYST NEMATODE THE EFFECT OF CROP ROTATION AND VARIETY SELECTION ON CHARCOAL ROT AND SOYBEAN GRAIN YIELD ANNUAL WEATHER SUMMARY FOR PARSONS ACKNOWLEDGEMENTS NOTE Trde nmes re used to identify products. No endorsement is intended, nor is ny criticism implied of similr products not mentioned. Contribution No S from the Knss Agriculturl Experiment Sttion. ii

5 EFFECT OF PREVIOUS SPRING STOCKING RATE ON FALL GRAZING AND SUBSEQUENT FEEDLOT PERFORMANCE OF STEERS 1 Kenneth P. Coffey nd Joseph L. Moyer Summry One hundred twenty-one mixed-breed steers (730 lb vg BW) were llowed to grze in the fll on fescue (IF) or fescue-ldino clover (IFL) pstures for n verge of 91 dys. Pstures hd been grzed previously t different stocking rtes in the spring nd left idle in the summer. Previous spring stocking rte hd little influence on fll grzing performnce nd psture crrying cpcity. Feedlot gin, feed consumption, nd feed cost declined (P<.05) nd dressing % incresed (P<.05) with incresing previous spring stocking rte. When verged within forges but cross the previous stocking rtes, clves grzing IFL gined 56% nd 40% more (P<.05) /hed nd /cre, respectively on 10 fewer (P<.05) grzing dys/cre. However, when plced in the feedlot, steers tht previously grzed IFL hd 4% lower (P=.05) gin, nd 3% higher (P<.05) intke but tended (P<.10) to hve higher mrbling scores thn steers tht previously grzed IF. Therefore, grzing fescue pstures t higher stocking rtes in the spring my hve little effect of subsequent fll grzing performnce nd crrying cpcity. Ldino clover ddition to IF pstures should hve substntil positive impct on cttle grzing performnce. Introduction In previously reported study (KAES Rep. Prog. 708), performnce by steers grzing IF nd IFL pstures declined s spring stocking rtes were incresed from pproximtely one steer/ to over three steers/. Avilble forge remining t the end of the spring grzing period vried substntilly with spring stocking rte. The purpose of this study ws to determine wht effects grzing IF nd IFL pstures t different stocking rtes in the spring would hve on fll grzing performnce nd crrying cpcity nd subsequent feedlot performnce by steers. Experimentl Procedures A totl of 243 mixed-breed stocker steers were divided into light- nd hevy-weight groups during the spring stocking rte study. Animls in the hevy-weight group ws used s tester steers in the spring stocking rte study, nd steers in the light-weight group were dded s necessry to crete different stocking rtes. At the end of the spring stocking rte comprisons, steers in the hevy-weight group were moved to the SEARC feedlot fcility t Mound Vlley, nd steers in the light-weight group (121 hed) were moved to bermudgrss pstures for the summer grzing period. On October 10 nd 11, 1991; September 3 nd 4, 1992; nd September 22 nd 23, 1993; steers in the light-weight group were dewormed nd llotted rndomly to one of eight 5-cre IF or IFL pstures. Initil stocking rtes for the fll 1 Apprecition is expressed to SmithKline Beechm, West Chester, PA for providing Bovishield 4+L5, Ultrbc/somnubc, nd Boveye vccintions; to Syntex Animl Helth, West Des Moines, IA for providing oxfendzole nd Synovex-S; to Mllinckrodt Veterinry, Mundelein, IL for De-Lice nd Sber Extr fly tgs; nd to Steve Clrk for use of experimentl nimls. 1

6 grzing period were determined bsed on initil vilble forge in ech psture, nd put-ndtke grzing system ws used to mintin similr quntities of vilble forge cross pstures. Pstures were fertilized ech fll with 40 lb/ ech of nitrogen, phosphte, nd potsh. Tester steers grzed their respective pstures for n verge of 91 dys nd then were processed ccording to routine procedures nd fed highconcentrte diet for n verge of 140 dys in the SEARC feedlot fcility. Following the feedlot period, steers were trnsported to Empori, KS nd slughtered t commercil slughter fcility. Crcss dt were collected following 24-hour chill. Costs of gin nd economic return were clculted using the following ssumptions. Estimted purchse price for the steers ws clculted ech yer bsed on locl mrket prices on the sle dte most recent to the beginning of the fll grzing period. Chrges for processing, fertilizer, seed, minerl, nd feed were bsed on ctul prices t the time of the study. Chrges for seeding nd fertiliztion were bsed on rtes published in the Knss Custom Rtes Bulletin. An interest rte of 10% nd lnd cost of $20/cre were ssumed. Seed nd seeding chrges s well s chrges for phosphte nd potsh fertiliztion were ssessed t hlf price, with the remining hlf ssessed to the spring grzing period. Results nd Discussion Spring stocking rte hd little effect on fll grzing performnce on IF or IFL pstures (Tble 1). However, the subsequent feedlot period following the fll grzing period ws ffected by previous spring stocking rte. Generlly, feedlot gin, intke, nd feed cost declined (P<.05) with previous spring stocking rte (Tble 2). The possibility of this reltionship ctully being rel nd expected is difficult to believe nd explin. Becuse fll psture performnce nd stocking rtes were not significntly ffected by previous spring stocking rte, we conclude tht the effect hppened without cler cuse nd effect reltionship. Grzing IFL pstures in the fll did prove to be dvntgeous during the grzing period compred with grzing IF pstures (Tble 3). Steers grzing IFL pstures gined 41.6 lb more (P<.01) during the grzing period nd.48 lb more/dy (P<.05) on 10 fewer (P<.05) grzing dys/. Fescue - ldino clover pstures produced 30.8 lb more (P<.05) steer weight/ thn IF pstures. Clculted psture returns bove lnd nd vrible costs were negtive when verged cross the 3-yer grzing study. These returns re bsed on purchsing steers weighing 730 lb in the fll. This wy, the returns re bsed on the vlue of the cttle going onto the pstures nd my not reflect ctul costs becuse the cttle ctully were purchsed erlier nd grzed on fescue then bermudgrss pstures. Less (P<.05) money ws lost with steers grzing IFL thn those grzing IF pstures when clculted s described. When plced in the feedlot, steers previously grzing IF pstures gined 17.5 lb more (P=.05) per hed while consuming.71 lb less (P<.05) DM per dy thn steers previously grzing IFL pstures. This increse in performnce by IF steers in the feedlot period probbly ws due to compenstory gin. Steers previously grzing IFL pstures tended (P<.10) to hve higher mrbling scores thn those previously grzing IF pstures. This higher mrbling score hs been shown in other studies from SEARC. One recommendtion to overcome much of the toxic effect on cttle grzing infected tll fescue is more closely mnging the fescue. This entils grzing fescue hevily in the spring to reduce seedhed formtion nd stimulte more lefy regrowth. In our previous study, this prctice substntilly reduced spring grzing performnce. Even with the pstures left idle during the summer nd pprent differences in vilble forge for the fll grzing period, little difference existed in fll performnce becuse of the different spring stocking rtes. Therefore, 2

7 this prctice, lthough it logiclly ppers to hve merit, does not seem to benefit niml performnce or overll return bove lnd nd vrible costs. Tble 1. Effect of Previous Spring Stocking Rte on Performnce by Steers Grzing Fescue or Fescue-Ldino Clover Pstures in the Fll Previous Stocking Rte on Previous Stocking Rte on Fescue Fescue - Ldino Item Psture phse Initil wt., lb Finl wt., lb Gin, lb Dily gin, lb Grz. dys/ Gin/, lb b Return, $/hed (22.80) (34.20) (22.20) (21.70) (13.40).12 (6.17) (1.69) Feedlot phse Finl wt., lb Gin, lb Dily gin, lb DM intke, lb/dy Feed:gin Feed cost, $ $/cwt. gin Return, $/hd (27.00) 4.53 (5.48) 4.75 (2.62) 2.48 (33.90) (29.50) Overll Return, $/hd (49.90) (29.70) (27.60) (16.90) (16.00) 2.60 (40.10) (31.20) Liner effect of stocking rte (P<.05). b Costs included the following: $5.08 processing, $10.69/ for fertilizer nd seed cost on IFL, $25.25/ for fertilizer on fescue, $18.00/cwt for minerl, 10% interest on clf nd fertilizer costs. 3

8 Tble 2. Crcss Chrcteristics of Steers Previously Grzing on Fescue or Fescue-Ldino Clover Pstures t Different Spring Stocking Rtes Stocking Rte on Stocking Rte on Fescue Fescue - Ldino Chrcteristic Dressing % Hot crcss wt., lb Bckft, in b Ribeye re, in c Mrbling score USDA Yield Grde Liner effect of stocking rte (P<.05). b Liner effect of stocking rte (P<.10). c = SelectE; = Select ; etc. Tble 3. Performnce by Steers Grzing Fescue or Fescue-Ldino Clover Pstures in the Fll Averged cross Previous Spring Stocking Rte Item Fescue Fescue-Ldino Psture Initil wt., lb Finl wt., lb. b Gin, lb. b Dily gin, lb. d.95 c 1.43 Grz. dys/ c 96.7 d 86.8 Gin/, lb. d 77.8 c Return, $/hed d (25.23) c (5.29) Feedlot phse Finl wt., lb Gin, lb. e f Dily gin, lb. e 3.39 f 3.26 DM intke, lb/dy d 25.6 c 26.4 Feed:gin d 7.7 c 8.3 Feed cost, $ $/cwt. gin f e Return, $/hd (5.81) (15.90) Overll Return, $/hd (31.02) (21.16) b Mens within row nd min effect with unlike superscripts differ (P<.01). cd Mens within row nd min effect with unlike superscripts differ (P<.05). ef Mens within row nd min effect with unlike superscripts differ (P<.10). 4

9 Tble 4. Crcss Chrcteristics of Steers Previously Grzing Fescue or Fescue-Ldino Clover Pstures in the Fll Averged cross Previous Spring Stocking Rte Chrcteristic Fescue Fescue-Ldino Hot crcss wt., lb Dressing % Bckft, in Ribeye re, in b Mrbling score d 556 c 590 USDA Yield Grde Bsed on ctul nonshrunk weight. b = SelectE; = Select ; etc. c Mens within row without common superscript letter differ (P<.10). 5

10 EFFECT OF FEEDLOT IMPLANT PROGRAM ON PERFORMANCE BY STEERS PREVIOUSLY GRAZING INFECTED FESCUE PASTURES 1 2 Kenneth P. Coffey, Frnk K. Brzle, nd Joseph L. Moyer Summry Thirty-nine mixed breed steers were llowed to grze on common Acremonium coenophilum-infected fescue psture for 77 dys beginning on April 1. On June 17, steers were llotted rndomly to six pens to provide two replictes of three different implnt procedures. Implnt progrms consisted of zernol initilly nd t reimplnting 76 dys lter (Z-Z), progesterone-estrdiol initilly nd t 76 dys (PE-PE), nd zernol initilly nd progesteroneestrdiol t 76 dys (Z-PE). Steers implnted with PE-PE hd greter (P<.10) feedlot gin nd dily gin thn those implnted with Z-Z. Steers implnted with Z-PE nd PE-PE tended to hve lower (P<.15) feed to gin rtios, lower (P<.15) feed cost of gin, nd hevier (P<.10) hot crcss weights thn those implnted with Z- Z. Therefore, progesterone-estrdiol ppered to be better feedlot phse implnt thn zernol for clves previously grzing infected fescue nd being finished during the summer months. Due to the sesonlity of fescue toxicity, extrpoltion of this dt to other times of the yer should be voided. Introduction Tll fescue is the predominnt cool-seson forge in Southest Knss nd much of the southestern United Sttes. Much of this forge is infected with the endophytic fungus A. coenophilum, which produces lkloids tht provide insect resistnce for the plnt but re toxic to cttle. The production of these lkloids nd their effects on cttle re very sesonl. In erlier studies, cttle previously consuming infected fescue showed greter response to zernol implnts thn those consuming noninfected fescue. This implies tht t lest some of the toxic fescue effects were offset by the implnt. This study ws designed to compre the effects of feedlot implnts on performnce by steers previously grzing infected fescue in lte spring. Experimentl Procedures Eighty mixed-breed steers were grzed on common 40 cre A. coenophilum-infected tll fescue psture for 77 dys beginning on April 1. All steers hd been vccinted previously ginst respirtory nd clostridil orgnisms upon rrivl nd hd been treted for internl nd externl prsites on April 1. Steers received pir of insecticide er tgs nd were vccinted ginst pinkeye on My 9. On June 17, steers were divided into light- nd hevy-weight groups. The 1 Apprecition is expressed to SmithKline Beechm, West Chester, PA for providing Bovishield 4+L5, Ultrbc/somnubc, nd Boveye vccintions; to Syntex Animl Helth, West Des Moines, IA for providing oxfendzole nd Synovex-S; to Mllinckrodt Veterinry, Mundelein, IL for Rlgro, De-Lice, nd Sber Extr fly tgs; nd to Steve Clrk for use of experimentl nimls. 2 Southest Knss Are Extension Livestock Specilist, Chnute, KS. 6

11 light-weight group ws moved to bermudgrss, nd the hevy-weight group (40 steers) ws trnsported to the Mound Vlley Unit of SEARC. These steers were vccinted ginst respirtory nd clostridil orgnisms nd llotted rndomly to six pens to provide two replictes of three different implnt procedures. Implnt progrms consisted of zernol initilly nd t reimplnting 76 dys lter (Z-Z), progesterone-estrdiol initilly nd t 76 dys (PE-PE), nd zernol initilly nd progesterone-estrdiol t 76 dys (Z- PE). Steers were fed diet of 80% ground grin sorghum, 15% corn silge, nd 5% protein supplement on dry mtter bsis. The protein supplement ws formulted to provide 50% crude protein nd to meet or exceed NRC requirements for minerls nd vitmins. Following 154-dy feedlot period, steers were trnsported to Empori, KS nd slughtered t commercil slughter fcility. Crcss mesurements were collected following 24-h chill. Results nd Discussion Steers implnted with PE-PE hd 40 lb greter (P<.10) feedlot gin nd.26 lb greter (P<.10) dily gin thn those implnted with Z-Z (Tble 1). Feedlot gin by steers implnted with Z-PE ws intermedite nd did not differ (P>.10) from tht of steers implnted with either Z-Z or PE- PE. Steers implnted with Z-PE nd PE-PE tended (P<.15) to hve lower feed to gin rtios nd lower feed cost of gin thn those implnted with Z-Z. From previous trils, we postulted tht zernol reduced the impct of fescue toxins in feedlot cttle. If this ws the cse, nd progesterone-estrdiol combintion would not reduce this toxic impct, steers implnted with zernol should hve shown n dvntge on erlier feedlot weights. Becuse no weight differentil ws detected from erly weights, we postulte tht for clves grzing lte spring fescue nd finished in the summer, the toxic-reducing effects of zernol nd progesterone-estrdiol re similr. Steers implnted with Z-PE nd PE-PE hd hevier (P<.10) hot crcss weights thn those implnted with Z-Z (Tble 2). No other crcss mesurements differed (P>.10) mong implnt tretments, lthough net crcss vlue ws numericlly (P=.25) lower from steers implnted with Z-Z thn from those implnted with Z-PE nd PE-PE. Therefore, progesterone-estrdiol ppered to be better feedlot phse implnt thn zernol for clves previously grzing infected fescue nd being finished during the summer months. We hve observed tremendous sesonlity in the response of cttle to both fescue toxicosis nd compounds tht my reduce its impct. Therefore, one should use these dt only for the time frme of the study nd should be cutious in extrpolting them to other times of the yer. We re currently evluting the sme tretments during winter feeding period from steers grzing infected fescue in the fll. This study should help determine if sesonl difference occurs in the response to feedlot implnts for steers previously grzing infected fescue. 7

12 Tble 1. Effect of Feedlot Implnt Progrm on Performnce by Steers Previously Grzing Infected Fescue Forge Initil nd Second Implnt Zernol Zernol Prog.+ Est. Item Zernol Prog.-Est. Prog.+ Est. Psture gin, lb Feedlot weights, lb 6/ / / / / Feedlot gin, lb b 501 b Dily gin, lb b 3.25 b 3.39 b 3.51 DM intke, lb Feed:gin c 7.11 d 6.71 d 6.65 Feed cost, $ $/cwt. gin c d d b Mens within row without common superscript letter differ (P<.10). cd Mens within row without common superscript letter differ (P<.15). Tble 2. Effect of Feedlot Implnt Progrm on Crcss Chrcteristics of Steers Previously Grzing Infected Fescue Forge Initil nd Second Implnt Zernol Zernol Prog. + Est. Chrcteristic Zernol Prog. + Est. Prog. + Est. Dressing % Hot crcss wt., lb c b b Bckft, in Ribeye re, in d Mrbling score % choice USDA Yield Grde Net crcss vlue, $ Bsed on ctul nonshrunk weight. bc Mens within row without common superscript letter differ (P<.10). d = SelectE; = Select 8

13 PERFORMANCE BY STEERS GRAZING INFECTED AND NONINFECTED FESCUE PASTURES WITH AND WITHOUT LADINO CLOVER OVERSEEDING 1 Kenneth P. Coffey, Joseph L. Moyer, nd Frnk K. Brzle 2 Summry A totl of 80 mixed-breed steers were llowed to grze on infected (IF) nd noninfected (FF) fescue pstures with (+L) nd without (-L) ldino clover for n verge of 209 dys in 2-yer grzing study. In 1993, steers grzing +L gined 83% more (P<.05) weight thn steers grzing -L pstures. In 1994, steers grzing FF gined 74 lb more (P<.15) thn those grzing IF. Environmentl conditions hd substntil impct on steer performnce, with wet cool summer sesons fvoring greter clover production nd greter niml gins. Introduction Tll fescue is the predominnt cool seson forge in Southest Knss nd much of the southestern United Sttes. A lrge percentge of the fescue in the United Sttes is infected with the endophytic fungus Acremonium coenophilum. This fungus produces lkloids tht ssist the plnt with pest tolernce but re toxic to livestock consuming the forge. Overseeding infected fescue pstures with ldino clover hs resulted in substntil performnce benefit to livestock grzing those infected pstures. This study ws conducted to compre performnce by steers grzing infected or noninfected fescue with nd without ldino clover overseeding. Experimentl Procedures A totl of 80 mixed-breed steers ws used in 1993 nd 1994 to determine the effects of forge type on grzing performnce. In ech yer, steers were vccinted ginst respirtory, clostridil, nd pinkeye infections nd treted for internl nd externl prsites. Steers were weighed on consecutive dys, strtified by weight nd llotted rndomly into groups of four hed ech. The groups were plced on 5-cre pstures of infected (IF) or noninfected (FF) fescue pstures with (+L) nd without (-L) ldino clover. Grzing periods extended from April 27 - Nov. 11, 1993 nd from Mr Oct. 27, All pstures were fertilized in the fll of ech yer with 40 lb/c ech of nitrogen (N), phosphte, nd potsh. Pstures hving no ldino clover overseeding (-L) were fertilized with n dditionl 80 lb N/ in the winter. Results nd Discussion Dt were nlyzed sttisticlly cross yers, but significnt (P<.05) yer fescue or clover tretment interction ws detected. This indictes tht the tretments did not respond the sme reltive to ech other in both yers. Therefore, the dt were nlyzed within yer nd re presented in Tble 1. No fescue type legume 1 Apprecition is expressed to SmithKline Beechm, West Chester, PA for providing Bovishield 4+L5, Ultrbc/somnubc, nd Boveye vccintions; to Syntex Animl Helth, West Des Moines, IA for providing oxfendzole nd Synovex-S; to Mllinckrodt Veterinry, Mundelein, IL for De-Lice, nd Sber Extr fly tgs; nd to Steve Clrk for use of experimentl nimls. 2 Southest Knss Are Extension Livestock Specilist, Chnute, KS. 9

14 interction ws detected (P<.05) in either yer. Therefore, the effect of +L or -L ws reltively the sme whether on IF or FF. In 1993, steers grzing FF gined 63 lb more thn those grzing IF, but the differences were not sttisticlly significnt. Steers grzing +L showed performnce dvntge (P<.10) over those grzing -L by July 15, nd this dvntge incresed throughout the grzing seson (Figure 1). Steers grzing +L pstures gined 190 lb more (P<.05) thn those grzing -L pstures. In 1994, steers grzing FF pstures gined 74 lb more (P<.15) thn those grzing IF. Fiftyone lb of the 74 lb gin differentil ws chieved by My 25 (Figure 2). Gins were similr between steers grzing +L nd -L pstures in The substntil dvntge from +L in 1993 nd the filure of n dvntge of +L in 1994 re probbly ttributble to different wether conditions ws wet yer with generlly cooler tempertures during the summer months. These types of wether conditions generlly fvor clover production. Wether conditions in 1994 were much more rid during the lte spring nd erly summer of 1994, resulting in poor clover production. In previous studies, steer gins hve benefitted gretly during wet yers nd not benefitted in dry yers from ldino clover overseeding. Therefore, one should consider these fctors when considering clovers for pstures in southestern Knss nd should look t the long-term benefits of clover rther thn the short-term filures. Tble 1. Performnce by Steers Grzing Infected nd Noninfected Fescue Pstures with nd without Ldino Clover Overseeding Fescue Type Ldino clover Item Non-infected Infected Present Absent 1993 Initil wt., lb Finl wt., lb b 729 Gin, lb c 418 d 228 Dily gin, lb c Initil wt., lb Finl wt., lb. e 877 f Gin, lb e 420 f Dily gin, lb e 1.95 f b Mens within row nd min effect with unlike superscripts differ (P<.10). cd Mens within row nd min effect with unlike superscripts differ (P<.05). ef Mens within row nd min effect with unlike superscripts differ (P<.15). d 10

15 Dte Figure 1. Weight of Steers Grzing Fescue Pstures in Dte Figure 2. Weight of Steers Grzing Fescue pstures in

16 PERFORMANCE BY STEERS GRAZING RYE/BERMUDAGRASS PASTURES WITH AND WITHOUT LADINO CLOVER OVERSEEDING 1 Kenneth P. Coffey nd Joseph L. Moyer Summry Eighty mixed-breed steers were llowed to grze on pstures of rye/bermudgrss (B) or rye/bermudgrss overseeded with ldino clover (BL) for 189 dys beginning on Mrch 15. Grzing gins were 48 lb greter (P<.05) but feedlot gins were 18 lb less (P>.10) from steers grzing B compred with those grzing BL. A higher percentge of B steers thn BL steers grded USDA Choice. Ldino clover production ws limited by rid wether conditions in lte spring nd erly summer. Under these conditions, ldino clover overseeding did not positively benefit performnce by steers grzing bermudgrss pstures. Introduction Bermudgrss is highly productive wrmseson forge cpble of exceptionl production if moisture nd fertilizer re vilble. Bermudgrss qulity declines drmticlly s it reches mturity. Ldino clover could provide n dditionl high-qulity forge for cttle grzing this lower-qulity bermudgrss nd thereby improve cttle gin nd reduce nitrogen fertilizer usge. Experimentl Procedures Eighty mixed-breed steers were llowed to grze on pstures of bermudgrss (B) or bermudgrss overseeded with ldino clover (BL) for 189 dys beginning on Mrch 15. Steers received vccintions ginst respirtory, clostridil, nd pinkeye orgnisms; were treted for internl nd externl prsites; nd were implnted with zernol. Steers were weighed on consecutive dys, strtified by weight, nd llotted rndomly to one of eight bermudgrss pstures tht hd been no-till drilled with 100 lb/ of cerel rye the previous fll. Pstures were llotted rndomly such tht four of the eight pstures were overseeded with 4 lb/ of ldino clover. All pstures were fertilized with 50 lb nitrogen (N)/ for the rye nd fertilized to soil test for phosphte nd potsh for the bermudgrss. Pstures overseeded with clover were fertilized with 50 lb N/ nd those without clover were fertilized with 100 lb N/ on My 19 nd 20. All pstures were clipped with rotry mower on July 6 nd 7 nd received n dditionl 50 lb N/ on July 7 nd Aug 5. Steers were weighed on 9/19 nd 9/20, trnsported to commercil feedlot fcility, nd fed finishing rtion for 140 dys. Following the finishing period, steers were trnsported to Empori, KS nd slughtered t commercil slughter fcility. Crcss mesurements were collected following 24-h chill. 1 Apprecition is expressed to SmithKline Beechm, West Chester, PA for providing Bovishield 4+L5, Ultrbc/somnubc, nd Boveye vccintions; to Syntex Animl Helth, West Des Moines, IA for providing oxfendzole; to Mllinckrodt Veterinry, Mundelein, IL for Rlgro, De-Lice, nd Sber Extr fly tgs; to Cl-West Seeds, Woodlnd, CA for providing ldino clover seed; nd to Richrd Porter for use of experimentl nimls. 12

17 Results nd Discussion Steers grzing B gined 43 lb more (P<.05) thn those grzing BL during the entire 189-dy grzing period (Tble 1). Overll gins during the grzing period were low nd verged.88 lb/dy. Low rinfll mounts in spring reduced forge production during the rye grzing period, resulting in gins of pproximtely one-hlf the mount normlly produced during this time. Gins during the bermudgrss growing period were somewht below the lb/dy tht we hve ttined in the lst 2 yers since chnging to more intensive mngement system (Figure 1). The gretest portion of gin occurred between My 10 nd July 6, with miniml gins occurring fter July 6. Becuse of low nd errtic rinfll, bermudgrss production ws reduced, thus limiting vilble forge for the grzing nimls. Ldino clover production ws miniml s well, presumbly lso becuse of the low nd errtic rinfll. Considering the combintion of poor clover production with lower N fertiliztion of BL, we cn conclude tht the reduced niml performnce by BL ws due to less bermudgrss production nd lower qulity of the forge produced. During the feedlot phse, steers previously grzing BL tended (P>.10) to gin more thn those previously grzing B. All steers were fed in common pen, so feed efficiency dt could not be collected. Steers previously grzing B hd higher % USDA Choice thn those previously grzing BL (Tble 2). Other crcss mesurements did not differ between previous forge type. In previous studies t SEARC, steers grzing fescue pstures overseeded with ldino clover hve hd higher % USDA Choice thn those previously grzing fescue pstures without clover. This reversed trend probbly ws due to greter grzing gins by steers grzing pstures without clover. Therefore, results of one grzing seson, indicte tht overseeding bermudgrss pstures with ldino clover my not be beneficil to niml performnce. However, should rinfll mounts be dequte in future yers, the results might reverse. Tble 1. Performnce by Steers Grzing Rye/Bermudgrss Pstures with nd without Ldino Clover Overseeding Item - Ldino + Ldino Psture phse Initil wt., lb Finl wt., lb. c d Gin, lb c d Dily gin, lb c Feedlot phse End wt., lb Gin Dily gin, lb b Mens within row nd min effect with unlike superscripts differ (P<.10). cd Mens within row nd min effect with unlike superscripts differ (P<.05). c 13

18 Tble 2. Crcss Chrcteristics of Steers Previously Grzing Rye/Bermudgrss Pstures with nd without Ldino Clover Overseeding Chrcteristic - Ldino + Ldino Hot crcss wt., lb Bckft, in Mrbling score % USDA Choice USDA Yield grde Net crcss vlue, $ b b Mens within row nd min effect with unlike superscripts differ (P<.05). Flgure 1. Weight of Steers Grzing Bermudgrss Pstures. 14

19 PERFORMANCE BY FINISHING STEERS OFFERED MAGNESIUM-MICA IN THE FEEDLOT RATION 1 Kenneth P. Coffey nd Frnk K. Brzle 2 Summry Forty-eight mixed breed steers from two sources were used in 141-dy feedlot study to compre control rtion (C) with rtion contining mgnesium-mic (MM; 9 lb/ton). No diet cttle source interctions were detected. Steer gin, efficiency, or cost of gin did not differ (P <.10) between diets. Mrbling score tended (P <.10) to be greter nd the percentge of cttle grding USDA Choice nd net crcss vlue were greter (P <.05) from steers fed MM. Steers rised t the KSU - Southest Agriculturl Reserch Center (SEARC) gined more (P <.10) weight, consumed more (P <.05) dry mtter, nd hd higher (P <.10) feed cost/hed thn purchsed mixed-breed steers. SEARC steers hd hevier (P <.01) hot crcss weights, tended (P <.10) to hve greter mrbling scores, hd higher (P <.01) USDA yield grdes, nd hd higher (P <.01) net crcss vlue thn purchsed steers. Therefore, feeding mgnesiummic in feedlot rtion my hve substntil economic impct on feedlot cttle. Experimentl Procedures Twenty-four mixed breed steers previously grzing tll fescue pstures nd 24 Angus Simmentl crossbred steers previously grzing smooth bromegrss were llotted in rndom strtified mnner within cttle source into eight groups of six hed ech on Jnury 20, The groups then were llotted rndomly to receive one of two finishing diets. Finishing diets consisted of 80% ground grin sorghum, 15% corn silge, nd 5% protein supplement (50% CP) on dry mtter bsis (Tble 1). The control supplement consisted primrily of soyben mel, whet middlings, ure, nd minerls to meet NRC (1984) requirements. In the other supplement, 9% of the whet middlings ws replced by mgnesium-mic. The soyben mel level ws ltered to replce the protein differentil between whet middlings nd mgnesium-mic. Steers were vccinted ginst IBR, BVD, PI 3, leptospirosis (5 strins), BRSV, nd clostridil infections (7-wy); dewormed; nd implnted (Synovex-S) upon rrivl t the feedlot. Steers were reimplnted fter 83 dys in the feedlot. Cttle received the finishing diet for 141 dys nd then were slughtered t commercil pcking plnt. Crcss dt were collected following 24-hour chill. Economic informtion ws clculted using ctul feed costs nd crcss vlues. Crcss prices were $106/cwt of hot crcss weight with discounts of $7 for USDA Select grde nd $20 for USDA Yield Grde 4 or crcss weights over 950 lb. Net crcss vlue ws clculted using the bse price of $106 with pproprite discounts. Live vlue of the steers ws clculted by 1 Apprecition is expressed to Micro-Lite, Inc., Chnute, KS for providing finncil support; to SmithKline Beechm, West Chester, PA for providing Bovishield 4+L5, nd Ultrbc/somnubc vccintions; nd to Syntex Animl Helth, West Des Moines, IA for providing oxfendzole nd Synovex-S. 2 Southest Knss Are Extension Livestock Specilist, Chnute, KS. 15

20 dividing net crcss vlue by the ending live weight pencil shrunk 4%. Results nd Discussion No diet by cttle source interction ws detected in the study. Therefore, dt re expressed within min effects. Steers receiving MM were (P<.05) hevier t 83 dys thn those receiving C (Tble 2). However, they were somewht hevier t the initition of the study thn C steers were. Finl weight nd gin did not differ (P>.10) between diets. Feed cost, feed efficiency, nd feed cost per /lb of gin likewise did not differ (P>.10) between diets. However, totl feed cost ws numericlly $16.47 lower per steer nd cost of gin ws numericlly $3.00 less per 100 lb of gin for steers fed MM thn for steers fed C. Steers of known prentge rised t SEARC were 119 lb hevier (P<.01) t the beginning of the feedlot period, were 198 lb hevier (P<.01) t the end of the 141-dy study, nd gined.56 lb/dy more (P<.10) thn purchsed steers of unknown prentge. Furthermore, SEARC steers consumed 4.4 lb more (P<.05) DM/dy nd hd $45.63/hed higher feed cost thn purchsed steers. Hot crcss weight, dressing percentge, ft thickness, nd USDA Yield Grdes did not differ (P>.10) between diets (Tble 3). Mrbling scores were 113 points or over one third of qulity grde higher (P<.10) from steers fed MM. Steers in this study grded poorly. Therefore, this increse in mrbling score resulted in substntil increse (P<.01) in the percentge of steers grding USDA Choice. This increse in the percentge of steers grding USDA Choice resulted in $50.92 higher (P <.05) crcss vlue nd $3.02/cwt higher (P =.11) live vlue for steers fed MM. SEARC steers hd 124 lb hevier (P<.01) hot crcss weights, higher (P <.01) USDA Yield Grdes, nd 111 points higher (P<.10) mrbling scores thn purchsed steers. These fctors contributed to $ greter (P<.01) net crcss vlue of SEARC steers. However, live vlue did not differ (P>.10) between cttle sources. Dt from this experiment re comprble in mny wys to dt from other experiments t SEARC using mgnesium-mic. It hs not shown ny dverse effects on DM consumption or performnce in previous studies. Furthermore, in those studies, mgnesium-mic hs been somewht beneficil for fiber digestion nd in ltering VFA profiles. In the current experiment, no dverse effects on feedlot gin, consumption, or efficiency were observed by substituting mgnesium-mic for whet middlings in the supplement. Mgnesium-mic pprently hd no effect on crcss weight or ft thickness, but hd n pprent substntil effect on crcss mrbling. One must remember tht this study utilized limited number of nimls (48) nd tht mrbling score is highly vrible mesurement. However, the fct tht, of the 24 hed per diet, 13 of the steers fed mgnesium-mic grded Choice, wheres only three of the steers fed the control diet grded Choice certinly csts shdow of doubt on the possibility tht the difference could be due to rndom chnce. However, biologicl explntion for the improved mrbling score by steers fed mgnesium-mic is lso not cler. However, this improvement represents significnt economic benefit, if other studies show similr findings. 16

21 Tble 1. Composition of Diets Offered to Finishing Steers Mgnesium- Ingredient Control Mic Ground grin sorghum Corn silge Soyben mel Whet middlings Ground limestone Ure TM slt Cne molsses Diclcium phosphte Potssium chloride Vitmin A,D,E premix Rumensin premix Mgnesium-mic

22 Tble 2. Performnce by Finishing Steers Offered Mgnesium-Mic (9 lb/ton) in the Feedlot Rtion Diet Cttle Source Mgnesium Item Control Mic Purchsed SEARC Period 1 (dy 0-83) b Initil wt., lb bc 83-dy wt., lb d Gin, lb d Dily gin., lb d Dily DM intke, lb Gin/feed, lb/lb d Feed cost, $ $/cwt. gin Totl (dy 0-141) b Initil wt., lb b Finl wt., lb e Gin, lb e Dily gin, lb d Dily DM intke, lb Gin/feed, lb/lb e Feed cost, $ $/cwt. gin Purchsed steers were exotic mixed-breed steers. SEARC steers were Angus Simmentl nd Simmentl Angus crossbred steers. b Differences between cttle sources were detected (P <.01). c Differences between diets were detected (P <.05). d Differences between cttle sources were detected (P <.05). e Differences between cttle sources were detected (P <.10). 18

23 Tble 3. Crcss Chrcteristics of Finishing Steers Offered Mgnesium-Mic (9 lb/ton) in the Feedlot Rtion Diet Cttle Source Mgnesium Chrcteristic Control Mic Purchsed SEARC b Hot crcss wt., lb c Dressing % Ft thickness, in Longissimus eye re, in def Mrbling score gh % USDA Choice b USDA Yield Grde bi Net crcss vlue, $ jk Live vlue, $/cwt Purchsed steers were exotic mixed-breed steers. SEARC steers were Angus Simmentl nd Simmentl Angus crossbred steers. b Differences between cttle sources were detected (P<.01). c Clculted using ctul unshrunk live weight. d = Select; 500 = Select. e Differences between diets were detected (P<.10). f Differences between cttle sources were detected (P<.10). g Differences between diets were detected (P<.01). h Differences between cttle sources were detected (P<.05). i Differences between diets were detected (P<.05). j Clculted by dividing net crcss vlue by the end live weight shrunk 4%. k Differences between diets were detected (P=.11). 19

24 EFFECT OF MAGNESIUM-MICA DURING GRAZING AND/OR FEEDLOT PHASES ON PERFORMANCE AND RUMEN FERMENTATION PRODUCTS OF STEERS 1 Kenneth P. Coffey, Lyle W. Loms, Joseph L. Moyer, nd Frnk K. Brzle 2 Summry Seventy-two mixed breed steers (679 lb vg. BW) grzing smooth bromegrss pstures were llotted rndomly to one of eight groups of nine steers ech nd fed 2.2 lb/dy of either control supplement (PC) or one contining.075 lb./dy of mgnesium-mic (PMM). Following the 112- dy grzing period, steers were plced in feedlot by psture group nd fed highconcentrte diet. The psture groups were split upon rrivl t the feedlot such tht two of the groups offered ech psture supplement were offered control supplement (FC) nd the two groups were offered supplement contining 10% mgnesium-mic (FMM). Steers fed PMM tended to gin 10 lb (P>.10) or.09 lb/dy more thn those fed PC during the psture phse. Supplementl mgnesium-mic hd no pprent effect on totl voltile ftty cid (VFA) production, but steers supplemented with PMM hd lower (P<.01) propionic cid molr concentrtions nd higher (P<.05) cetic to propionic cid rtios on My 6. Neither previous psture supplement nor feedlot supplement ffected (P>.10) steer gin or efficiency. Steers fed PMM hd higher dressing % (P<.05) nd net crcss vlue (P<.06) nd numericlly (P>.10) hd higher mrbling scores nd % USDA Choice thn those fed PC. No differentil effect of feedlot supplement ws detected for crcss mesurements. Positive benefits on performnce by supplementing grzing cttle with mgnesiummic were minor, possibly becuse of high levels of gin by ll of the cttle used in this study. Considering these dt nd those from previous study, the effect of mgnesium-mic on subsequent mrbling scores does pper to be rel. Also, the effect my be estblished if mgnesium-mic is fed in psture or finishing phse. Introduction Previous work t SEKES hs shown tendency for incresed totl VFA concentrtions nd more fvorble VFA profile from cttle offered mgnesium-mic. Similr chnges with other commercilly vilble compounds hs improved performnce by grzing cttle. Crcss mrbling scores nd the percentge of steers grding Choice ws higher from feedlot steers fed mgnesium-mic (MM) compred with steers fed our typicl feedlot diet in nother study. Our objective ws to mesure rumen fermenttion products, grzing nd subsequent feedlot performnce, nd crcss chrcteristics of cttle offered mgnesium-mic in the grzing nd/or feedlot phses. 1 Apprecition is expressed to Micro-Lite Inc., Chnute, KS for providing finncil support; to SmithKline Beechm, West Chester, PA for providing Bovishield 4+L5, Ultrbc/somnubc, nd Boveye vccintions; to Syntex Animl Helth, West Des Moines, IA for providing oxfendzole nd Synovex-S; nd to Mllinckrodt Veterinry, Mundelein, IL for Rlgro, De-Lice, nd Sber Extr fly tgs. 2 Southest Knss Are Extension Livestock Specilist, Chnute, KS. 20

25 Experimentl Procedures Seventy-two mixed-breed steers were received t the KSU - Southest Agriculturl Reserch Center in November, Upon rrivl, steers were vccinted ginst seven clostridil strins, Hemophilus somnus, IBR, BVD, PI, 3 BRSV, nd five strins of leptospirosis nd were dewormed. Steers were distributed rndomly onto cre smooth bromegrss pstures, fed hy d libitum, nd fed 2 lb/dy of 20% CP supplement during the winter. Steers were weighed without prior removl of feed nd wter on April 6 nd 7 to determine n initil weight nd llotted rndomly by weight into eight groups of nine hed ech. Rumen smples were collected rndomly vi stomch tube from three steers per group of nine hed t the time of weighing on the second dy. Steers lso were vccinted ginst pinkeye, dewormed, nd implnted (zernol) on April 7. The eight groups of steers were llotted rndomly to one of eight 10- smooth bromegrss pstures. Hlf of the steer groups were fed control supplement (C) contining 84% ground grin sorghum, 15% cottonseed mel, nd 1% soyben oil, wheres hlf were offered supplement contining 80.63% ground grin sorghum, 15% cottonseed mel, 1% soyben oil nd 3.37% mgnesium-mic t rte of 2.2 lb/hed dily (MM). This level ws fed to provide.075 lb of mgnesium-mic/hed dily. Steers were rotted through the pstures t 14-dy intervls to minimize the effect of psture vrition nd were weighed t 28-dy intervls throughout the 112- dy grzing study. Rumen smples were collected from three steers determined rndomly per group on dys 0, 28, 56, nd 112 of the study, nd VFA concentrtions were determined. Finl weights were mesured without prior removl of feed nd wter on July 27 nd 28, nd the steers were trnsported to the SEARC feedlot fcility t Mound Vlley, KS. Groups of steers were blocked by previous psture tretment nd llotted rndomly to receive one of two finishing diets. Finishing diets consisted of 80% ground grin sorghum, 15% corn silge, nd 5% protein supplement (50% CP) on dry mtter bsis. The control supplement (FC) consisted primrily of soyben mel, whet middlings, ure, nd minerls to meet NRC (1984) requirements (Tble 1). The other supplement contined mgnesium-mic (FMM) t 10% replcing whet middlings. The soyben mel level ws ltered to replce the protein differentil between whet middlings nd mgnesium-mic. Steers were vccinted ginst IBR, BVD, PI 3, leptospirosis (5 strins), BRSV, nd clostridil infections (7-wy); treted for internl nd externl prsites; nd implnted upon rrivl t the feedlot. Steers were reimplnted fter 69 dys in the feedlot. At the end of 120-dy finishing period, steers were slughtered t commercil pcking plnt, nd crcss dt were collected following 24-hour chill. Results nd Discussion Steers fed PMM tended (P>.10) to weigh 12.5 lb more t the end of the 112-dy grzing period nd to gin 10 lb more during the study thn steers fed PC (Tble 2). No differences were detected (P>.10) for totl VFA t ny of the smpling dtes (Tble 3). Molr concentrtions of propionte were greter (P<.01) from PC thn from PMM on My 6, but no differences were detected on the other smpling dtes. The cetic to propionic cid rtio ws greter (P<.05) from PMM thn from PC on My 6. Molr percentges of other VFA on My 6 nd other dtes did not differ (P<.10) between PC nd PMM. No significnt psture tretment feedlot tretment interctions were detected (P<.05) for ny of the performnce or crcss mesurements. Therefore, feedlot dt were pooled cross the min effects of psture tretment nd feedlot tretment. Neither psture tretment nor feedlot tretment ffected (P<.10) feedlot gin, efficiency, or cost of gin (Tble 4). These dt re in greement with those from the previous study conducted t SEARC. One must recognize 21

26 tht the steers were lrge ccording to tody's feedlot stndrds. The steers gined extremely well during the psture phse nd, therefore, were hevier going into the feedlot period. During the time frme when the steers were slughtered, hevy-weight steer crcsses were being discounted s much s $23/cwt. This encourged us to mrket the steers erlier thn they should hve been to prevent substntil economic loss. Feedlot supplements hd no effect on ny of the crcss mesurements evluted in this study. However, previous psture supplement hd n effect on severl mesurements (Tble 5). Steers fed PMM tended to hve hevier (P =.11) hot crcss weights nd hd higher (P <.05) dressing percentge thn those fed PC. Although not sttisticlly different (P <.10), steers fed PMM hd 50% increse in the percentge grding USDA Choice compred with steers fed PC. These fctors combined to produce $19.92 higher (P <.06) net crcss vlue nd $1.50/cwt. higher (P <.05) live vlue for those steers. The low percentge of steers grding Choice my be ttributed to the erlier mrketing. The reson for the tendency for difference in the percentge of steers grding USDA Choice between psture supplements is not cler. The lck of psture tretment feedlot tretment interction is indictive of similr responses to tretments cross production phses. Of the steers fed PC, five of the 18 steers fed FC nd five of the steers fed FMM grded USDA Choice. Of the steer fed PMM, seven of the 18 steers fed FC nd eight of the 18 steers fed FMM grded USDA Choice. Therefore, no dvntge in % USDA Choice ws gined by feeding PC steers mgnesium-mic in the feedlot period, nd no dditionl dvntge ws gined by feeding PMM steers mgnesiummic in the feedlot. Therefore, the response ppers to be primrily due to the psture phse mgnesium-mic supplementtion. It is possible tht the high rtes of gin observed during the psture phse in this study offset the dvntge of supplementl mgnesiummic, nd tht greter dvntge might be observed should overll grzing gins be lower. Considering the feedlot dt nd those of our previous feedlot study, we cn conclude tht mgnesium-mic fed t level of 9-10 lb/ton of dry mtter should hve miniml effects on gin nd efficiency of feedlot steers. Therefore, feed cost then becomes the issue in determining whether or not to include mgnesium-mic in the rtion when looking t growth prmeters. The effect of the psture- phse supplementl mgnesium-mic on subsequent crcss qulity nd vlue is perplexing in light of the bsence of n effect of feedlot-phse mgnesium-mic supplementtion in this study. Some of the feedlot effect my hve been msked by previously receiving mgnesium-mic in the psture supplement. However, the lck of psture tretment by feedlot tretment interction does not substntite this. The rel dvntge, other thn cost, of including mgnesium-mic in steer rtions or supplements ppers to be in incresing the number of steers tht will grde USDA Choice nd, thereby, incresing the net crcss vlue to the producer. 22

27 Tble 1. Composition of Supplements Offered to Finishing Steers Mgnesium- Ingredient Control Mic Soyben mel Whet middlings Ground limestone Ure TM slt Cne molsses Potssium chloride Vitmin A,D,E premix Rumensin 80 premix Mgnesium-mic Supplement ws fed t 5% of the rtion dry mtter. Tble 2. Grzing Performnce by Steers Grzing Smooth Bromegrss Pstures nd Fed Mgnesium-Mic in Grin Supplement Mgnesium- Item Control Mic Initil wt., lb Finl wt., lb Gin, lb Gin, lb/dy No significnt differences (P <.10) were detected. 23

28 Tble 3. Ruminl Fermenttion Products by Steers Grzing Smooth Bromegrss nd Fed Mgnesium-Mic in Grin Supplement My 6 June 5 July 28 Item PC PMM PC PMM PC PMM Totl VFA, mm mole/100 mole Acetic Propionic b 18.0 c Isobutyric Butyric Isovleric Vleric Acetic: propionic c 3.6 b C=control supplement; MM=supplement contining.075 lb/d mgnesium-mic. b,c Mens within row nd dte without common superscript letter differ (P <.05). Tble 4. Performnce by Finishing Steers Offered Mgnesium-Mic in Psture or Feedlot Supplement b c Psture Tretment Feedlot Tretment Item PC PMM FC FMM Totl (dy 0-120) Initil wt., lb Finl wt., lb Gin, lb Dily gin, lb Dily DM intke, lb Gin/feed, lb/lb Feed cost, $ $/cwt. gin Mgnesium-mic levels were.075 lb/dy in the psture supplement nd 10 lb/ton DM in the feedlot rtion. b No significnt differences were detected (P <.10). c PC nd PMM = control nd mgnesium-mic supplements during the psture phse; FC nd FMM = control nd mgnesium-mic supplements during the feedlot phse. 24

29 Tble 5. Crcss Chrcteristics of Finishing Steers Offered Mgnesium-Mic in Psture or Feedlot Supplement c Psture Tretment Feedlot Tretment Chrcteristic PC PMM FC FMM c Hot crcss wt., lb de Dressing % Ft thickness, in Longissimus eye re, in f Mrbling score % USDA Choice USDA yield grde g Net crcss vlue, $ eh Live vlue, $/cwt Mgnesium-mic levels were.075 lb/dy in the psture supplement nd 10 lb/ton DM in the feedlot rtion. b PC nd PMM = control nd mgnesium-mic supplements during the psture phse; FC nd FMM = control nd mgnesium-mic supplements during the feedlot phse. c Differences between psture supplements were detected (P=.11). d Clculted using ctul unshrunk live weight. e Differences between psture supplements were detected (P<.05). f = Select; 500 = Select. g Differences between psture supplements were detected (P<.06). h Clculted by dividing net crcss vlue by the end live weight shrunk 4%. 25

30 EFFECTS OF YEAST AND SODIUM BICARBONATE ON RUMINAL DIGESTION AND INTAKE OF HIGH CONCENTRATE DIETS 1 Kenneth P. Coffey Summry Two experiments were conducted to compre responses on intke nd rumen fermenttion to supplementl sodium bicrbonte nd yest. In both experiments, four ruminlly fistulted nonpregnnt nonlctting Trentise cows were used in 4-period experiment during which ech of four diets ws fed to the four cows. In Exp. 1, cows were fed bsl diet of corn nd lflf hy nd supplemented with sodium bicrbonte twice dily (B), yest either once (1Y) or twice dily (2Y), or control supplement (C). Intke, ruminl ph, nd ruminl voltile ftty cids (VFA) did not differ (P <.10) mong tretments. In situ (nylon bg) dry mtter (DM) nd neutrl-detergent fiber (NDF) disppernce t 48 h tended (P <.10) to be greter from cows fed B compred with those fed 1Y nd 2Y, nd DM digestion lg phse tended to be lower (P <.10) from those cows thn those fed 1Y nd 2Y. Dry mtter digestion lg phse tended (P <.10) to be lower from cows fed 1Y nd 2Y thn from cows fed C. In Exp. 2, ruminlly fistulted cows were fed bsl diet of corn silge, dry-rolled corn, ground (1 inch) lflf hy, nd soyben mel. Sodium bicrbonte ws fed twice dily (B) wheres yest ws fed once dily lone (Y) or in combintion with bicrbonte (YB). Intke, ruminl ph, nd mmoni did not differ (P <.10) mong tretments. When verged cross smpling times, cows fed B hd greter molr concentrtions of cetic (P <.10) nd isovleric cids (P <.05). In situ dry mtter (DM) disppernce t 24 nd 48 h tended (P <.10) to be greter, nd the digestion rte ws numericlly (P =.19) greter from cows fed B thn from those not fed B. In situ neutrl-detergent fiber (NDF) disppernce tended (P<.10) to be greter t 24 h nd ws greter (P<.05) t 48 h from cows fed B compred with those not fed B. Cows fed Y tended (P<.16) to hve greter NDF disppernce t 96 h nd slower NDF digestion rte nd tended (P<.10) to hve shorter digestion lg nd greter digestible NDF frction thn cows not fed Y. Cows fed Y hd greter (P<.05) weight chnge during the experimentl periods thn those not fed Y, possibly indictive of ccumultion of greter fill which ultimtely could led to greter niml performnce. Therefore, cttle fed high concentrte diet nd supplemented with yest once dily nd/or sodium bicrbonte did show limited improvements in some mesurements deling with fiber digestion. However, neither supplement pprently ffected intke or ruminl fermenttion to the extent of ltering ruminl ph or VFA production. Therefore, other thn limited improvements in some mesurements, ll tretments proved ineffective in improving prmeters tht might benefit niml performnce. 1 Apprecition is expressed to Agrimeric, Inc., Northbrook, IL for finncil ssistnce. 26

31 Experimentl Procedures Experiment 1 Four nonpregnnt nonlctting Trentise cows fitted with rumen cnnule were offered bsl diet of pproximtely 69% dry-rolled corn, 30% ground (1 inch) lflf hy, nd 1% soyben oil in four-period experiment. The experiment ws designed such tht ech of four tretments ws fed to one cow during ech period, nd ech cow received ech tretment once during the experiment. Tretments consisted of 1) control supplement offered twice dily (C); 2) supplement contining.5g yest offered t 7AM nd control supplement offered t 3PM (1Y); 3) supplement contining 50 g sodium bicrbonte offered t 7AM nd 3PM (B); nd 4) supplement contining.25 g yest offered t 7AM nd 3PM (2Y). Supplements consisted primrily of ground corn nd molsses nd were formulted to meet or exceed NRC requirements for mcro nd trce minerls, vitmins, nd MGA. Supplements were used s crriers for yest nd bicrbonte nd were fed t rte of.5 lb t 7AM nd 3PM. Yest nd bicrbonte were weighed individully nd mixed into the supplement prior to ech feeding. Ech period consisted of 10-d dietry dpttion followed by 4-d smple collection period. Rumen smples were collected 0, 4, nd 8 hours following the 7AM feeding nd 2 h fter the 3PM feeding on 2 consecutive dys nd ruminl ph ws mesured. Nylon bgs contining lflf hy were suspended in the rumen for times up to 96 hours. Periods two nd four immeditely followed periods one nd three, respectively. Cows were removed from the metbolism fcility following period two for 7- dy rest nd exercise period. During tht time, they were offered the bsl diet with the control supplement. Experiment 2 Four nonpregnnt nonlctting Trentise cows fitted with rumen cnnule were used in four-period experiment similr to tht described for Exp. 1. A bsl diet of pproximtely 40.5% corn silge, 39.6% dry-rolled corn, 15.2% ground (1 inch) lflf hy, nd 4.7% soyben mel ws supplemented with (Y) or without (No Y) yest, nd with (B) or without (No B) sodium bicrbonte. Yest ws fed t 7:30AM t rte of.5g blended with the dily supplement. Sodium bicrbonte ws fed t 7:30AM nd 3:30PM t rte of 50 g sodium bicrbonte blended with the dily supplement. The supplement consisted primrily of ground corn nd molsses nd ws formulted to meet or exceed NRC requirements for mcro nd trce minerls, vitmins, nd MGA. Periods nd smpling procedures were similr to those described for Exp. 1. Results nd Discussion Experiment 1 Dry mtter intkes did not differ (P>.10) mong tretments (Tble 1) nd verged 2% of body weight. Ruminl ph ws ffected (P<.05) by smpling time but not by tretment (Tble 2), nd tretment smpling time interction ws not detected (P>.10) for ruminl ph. Totl VFA s well s molr proportions of cetic, isobutyric, butyric, isovleric, nd vleric cid, nd the cetic to propionic cid rtios vried (P<.05) cross smpling times. The tretment smpling time interction tended (P<.10) to be significnt for molr proportion of cetic cid. However, totl VFA concentrtion or molr percentges of different VFA did not differ (P<.10) between tretments when verged cross smpling times nd dys. In situ (nylon bg) DM disppernce t 48 hours of incubtion tended to be greter (P<.10) from cows offered B thn from those offered 1Y or 2Y (Tble 3). In situ disppernce t 48 hours from cows offered either 1Y or 2Y did not differ (P<.10) from tht by cows offered C. Cows fed B tended to hve lower (P<.10) in situ indigestible DM frction nd shorter (P <.01) DM digestion lg phse thn cows fed the other tretments. In situ digestible nd 27

32 indigestible DM frctions did not differ (P<.10) mong cows fed 1Y, 2Y, or C, but cows fed 1Y or 2Y hd shorter (P<.01) DM digestion lg phses thn cows fed C. Dry mtter disppernce rtes did not differ (P<.10) mong tretments. In situ NDF disppernce t 48 hours of incubtion tended to be greter (P<.10) from cows fed B thn from those fed 1Y or 2Y (Tble 4). The digestible NDF frction from cows fed 2Y tended to be lower (P<.10) thn tht from cows fed B or 1Y. Disppernce rtes of NDF did not differ mong tretments. Experiment 2 Dry mtter intkes did not differ (P>.10) between min effects (Tble 5) nd verged 1.8% of body weight. Averge weight tended (P<.10) to be greter from B thn No B, nd weight chnge during the experimentl periods ws greter (P<.05) from Y thn from No Y. This is probbly indictive of the cows fed Y chieving greter ruminl fill thn those fed No Y. Ruminl ph nd mmoni were ffected (P<.01) by smpling time but not by supplements (Tble 6), nd smpling time interctions with either min effect were not detected (P<.05). Isovleric cid concentrtions were higher (P<.05) from cows fed B thn from those fed No B. However, totl VFA concentrtion nd molr percentges of the other VFA did not differ (P<.10) between min effects when verged cross smpling times nd dys. In situ DM disppernce t 24 nd 48 hours of incubtion tended to be greter (P<.10) from cows fed B thn from those fed No B (Tble 7). However, disppernce t 72 nd 96 hours of incubtion did not differ (P>.10) between cows fed B nd those fed No B. This indictes tht supplementl sodium bicrbonte did not ffect the mximum extent of digestion but tht the extent ws reched t shorter incubtion time. This is verified by similr digestible frctions (f) d between cows fed B nd No B while in situ DM disppernce rte tended (P =.19) to be fster from cows fed B thn from those fed No B. These fctors typiclly might led to improved intke in cttle consuming diets with high roughge content. In this study, cows fed B consumed 5.3 % more DM thn those fed No B, but the difference ws not sttisticlly significnt. Yest did not ffect in situ DM disppernce. In situ NDF disppernce t 24 hours of incubtion tended to be greter (P<.10) nd disppernce t 48 hours ws greter (P<.05) from cows fed B thn from those fed No B (Tble 8). However, sodium bicrbonte supplementtion hd no effect (P<.10) on digestible or indigestible NDF frctions or on NDF digestion rte. Yest did not ffect NDF disppernce t ny digestion time, but the digestible NDF frction from cows fed Y tended to be higher (P<.10) thn tht from cows fed No Y. Cows fed Y lso tended to hve shorter (P<.10) digestion lg time but slower (P =.12) digestion rte thn cows fed No Y. Altering NDF digestion cn hve substntil impct on intke of high roughge diets, but hs much less of n effect in high concentrte diet becuse of intke regultion by chemosttic mechnisms rther thn from gut distention. Therefore, the impct of NDF digestion rte on interprettion of other dt is probbly not s effective s it might be in diet with higher roughge content. At the levels fed in this experiment, supplementl yest hd little effect on intke, ruminl fermenttion, or in situ disppernce of lflf hy DM. Although supplementtion with yest did hve positive effect on NDF digestible frction nd digestion lg, these improvements were not effective in improving intke. Supplementtion of the high-concentrte diet with sodium bicrbonte did hve n pprent positive effect on lflf hy disppernce from nylon bgs suspended in therumen, but hd little effect on intke or ruminl fermenttion products. 28

33 However, the mgnitude of improvements demonstrted here would not led one to believe tht niml performnce would be improved substntilly by either product evluted in these studies. Tble 1. Intke of Corn-Alflf Hy Diet by Cows Fed Sodium Bicrbonte or Yest - Exp. 1. Tretment Item C B 1Y 2Y Animl weight, lb d DM intke, lb d DM intke, % BW No significnt differences were detected (P<.10). Tble 2. Ruminl ph nd Voltile Ftty Acid Concentrtions from Cows Fed Corn-Alflf Hy Diet Supplemented with Sodium Bicrbonte or Yest - Exp. 1. Tretment Item C B 1Y 2Y ph Totl VFA, mm mole/100 mole Acetic Propionic Isobutyric Butyric Isovleric Vleric Acetic:propionic Tretment differences or tretment time interctions were not detected (P<.10). 29

34 Tble 3. In Situ (Nylon Bg) Dry Mtter Digestibility from Cows Fed Corn-Alflf Hy Diet Supplemented with Sodium Bicrbonte or Yest - Exp. 1. Tretment Item C B 1Y 2Y Time, hours b b 51.3 b f, d % b b 35.3 b 33.3 f, i % 28.0 b f, s % k, d1 h k, d2 h lg time, hours 9.0 c 1.7 b 5.3 b 5.4,b,c Mens within row without common superscript letter differ (P<.10). f = the potentilly digestible frction; f = the potentilly indigestible frction;f = the soluble frction d i s of the substrte; k d1 = the frctionl digestion rte constnt clculted using non-liner SAS; k d2 = the frctionl digestion rte constnt clculted using regression of the nturl logrithm of the potentilly digestible substrte remining ginst time. 30

35 Tble 4. In Situ (Nylon Bg) Neutrl-Detergent Fiber Digestibility from Cows Fed Corn-Alflf Hy Diet Supplemented with Sodium Bicrbonte or Yest - Exp. 1. Tretment Item C B 1Y 2Y Time, hours b b 38.2 b f, d % b b 36.5 f, i % b 51.4 b f, s % k, d h k, d h lg time, hours ,b Mens within row without common superscript letter differ (P<.10). f = the potentilly digestible frction; f = the potentilly indigestible frction;f = the soluble frction d i s of the substrte; k d1 = the frctionl digestion rte constnt clculted using non-liner SAS; k d2 = the frctionl digestion rte constnt clculted using regression of the nturl logrithm of the potentilly digestible substrte remining ginst time. Tble 5. Intke of High-Concentrte Diet by Cows Fed Sodium Bicrbonte or Yest - Exp. 2. Yest Sodium Bicrbonte Item Control Yest Control Bicrb. Animl weight, lb d DM intke, lb d DM intke, % bw b Weight chnge, lb Diets supplemented with sodium bicrbonte differed (P<.10) from those tht were not supplemented with sodium bicrbonte. b Diets supplemented with yest differed (P<.05) from those tht were not supplemented with yest. 31

36 Tble 6. Ruminl ph, Ammoni nd Voltile Ftty Acid Concentrtions from Cows Fed High- Concentrte Diet Supplemented with Sodium Bicrbonte or Yest - Exp. 2. Yest Sodium Bicrbonte Item Control Yest Control Bicrb. ph Ruminl mmoni, mm Totl VFA, mm mole/100 mole Acetic Propionic Isobutyric Butyric b Isovleric Vleric Acetic:propionic Sodium bicrbonte time interction ws significnt (P<.05). b Diets supplemented with sodium bicrbonte differed (P<.05) from those not supplemented with sodium bicrbonte. Tble 7. In Situ (Nylon Bg) Dry Mtter Digestibility (%) from Cows Fed High-Concentrte Diet Supplemented with Sodium Bicrbonte or Yest - Exp. 2. Yest Sodium Bicrbonte Item Control Yest Control Bicrb. Time, hours f, d % f, i % k, d h lg time, hours Diets supplemented with sodium bicrbonte differed (P<.10) from those tht were not supplemented with sodium bicrbonte. f d = the potentilly digestible frction; f i = the potentilly indigestible frction; k d = the frctionl digestion rte constnt clculted using non-liner SAS. 32

37 Tble 8. In Situ (Nylon Bg) Neutrl-Detergent Fiber Digestibility (%) from Cows Fed High- Concentrte Diet Supplemented with Sodium Bicrbonte or Yest - Exp. 2. Yest Sodium Bicrbonte Item Control Yest Control Bicrb. Time, hours b c d f, d % f, i % c k,h d d lg time, h Diets supplemented with sodium bicrbonte differed (P<.10) from those tht were not supplemented with sodium bicrbonte. b Diets supplemented with sodium bicrbonte differed (P<.05) from those tht were not supplemented with sodium bicrbonte. c Diets supplemented with yest differed (P<.16) from those tht were not supplemented with yest. d Diets supplemented with yest differed (P<.10) from those tht were not supplemented with yest. f d = the potentilly digestible frction; f i = the potentilly indigestible frction; k d = the frctionl digestion rte constnt clculted using non-liner SAS. 33

38 ALFALFA VARIETY PERFORMANCE IN SOUTHEASTERN KANSAS Joseph L. Moyer Summry Alflf yields for 1994 included five cuttings. For the yer, 'Riley yielded less thn 12 other cultivrs. Over the 5-yer period, Grst 630 hs consistently produced more thn Riley. Introduction The importnce of lflf s feed crop nd/or csh crop hs incresed in recent yers. The worth of prticulr vriety is determined by mny fctors, including its pest resistnce, dptbility, longevity under specific conditions, nd productivity. Experimentl Procedures The 15-line test ws seeded (12 lb/) in April, 1990 t the Mound Vlley Unit. Plots were fertilized with lb/ of N-P2O5-K2O on 11 Mrch, Five hrvests were obtined in Growing conditions were generlly fvorble (see wether summry), except bit dry in July for optimum growth. No prticulr insect or disese problems were noted. Results nd Discussion Forge yields of ech of the five cuttings, totl 1994 production, nd 5-yer totls re shown in Tble 1. Cut 1 yield ws higher from 630 thn from DK 135, Riley, or WL-320. Yield of 5472 ws higher in cut 3 thn tht of Riley nd DK 135 nd higher in cut 4 thn tht of 10 cultivrs. Totl 1994 yields of 5472, 630, 'Mgnum III', 'Apollo Supreme', nd WL 317 were higher thn yields of Riley, DK 135, nd 'Cimmron VR'. After 5 yers of testing, yields of the highest- nd lowestrnking cultivrs were seprted by more thn 12 percentge points (3.5 tons). 34

39 Tble 1. Forge Yields of the Alflf Vriety Test in 1994, Mound Vlley Unit, Southest Agriculturl Reserch Center Yr Source Vriety 5/6 6/7 7/5 8/3 9/13 Totl Totl % ICI (Grst) bc 1.71bcd 0.37bc bc 7.25bc Dirylnd Mgnum III 2.36b 1.68bcd 0.52b bc Crgill Trident II 2.17bcd 1.68bcd 0.44bc bc 7.26bc Grst bc bc Americ's Alflf Apollo Supreme 2.27bc 1.63bcd 0.48bc bc Pioneer bc 1.58bcd 0.40bc bc 7.10bc 30.28b Pioneer bcd 1.80b W-L Reserch WL bc 1.60bcd 0.41bc bc b Agripro Drt 2.30bc 1.78bc 0.40bc c 7.22bc 30.04b Agripro Ultr 2.12bcd 1.69bcd 0.49bc b 7.30b 30.09b W-L Reserch WL bcd 1.70bcd 0.42bc bc 7.14bc 29.63b Pioneer bcd 1.68bcd 0.46bc bc 7.20bc 29.50b Gret Plins Res. Cimrron VR 2.10bcd 1.56cd 0.35bc c 6.62bcd 28.73bc DeKlb DK d 1.52de 0.33bc bc 6.56cd 27.93c KS AES & USDA Riley 2.00cd 1.35e 0.26c bc 6.36d 27.48c Averge LSD(.05) Mens within column followed by the sme letter do not differ (P=.05) ccording to Duncn's test.

40 FORAGE PRODUCTION OF BERMUDAGRASS CULTIVARS IN SOUTHEASTERN KANSAS Joseph L. Moyer nd Chrles M. Tliferro 2 Summry In the third hrvest yer of the test, experimentl 74 X 11-2 yielded more first-cut nd totl forge thn ll other cultivrs, including ll four nmed vrieties. Totl 1994 production ws higher from 'Hrdie' nd six experimentls thn from nine other cultivrs. Introduction Bermudgrss cn be high-producing, wrm-seson, perennil forge for southestern Knss. Producers hve profited considerbly from the replcement of the common bermuds with the vriety 'Midlnd'. Developments in bermudgrss breeding should be monitored closely to speed doption of improved types. Experimentl Procedures Plots were sprigged with plnts in pet pots on 28 June, 1991 t the Mound Vlley Unit. Plots were 15 x 20 ft ech, in four rndomized complete blocks. Plots were spryed on 4 April with 1.5 lb/ of metolchlor. Appliction of lb/ of N-P2O5-K2O ws mde on 19 My, followed by fertiliztion with 53 lb/ of N on 4 August. Strips 20 x 3 ft were cut on 10 June, 29 July, nd 10 October, Subsmples were collected for determintion of moisture. Visul rtings of vegettive spred were mde on 24 June. Results nd Discussion In the first cutting, Experimentl 74 X 11-2 yielded more forge thn ny other cultivr (Tble 1). However, 74 X 11-2 hs spred very little from the originl plnts in the 3 yers since sprigging, brely covering the width of the hrvest strip. Experimentl LCB84 X yielded more thn 14 other cultivrs, including 'Midlnd', 'World Feeder', 'Greenfield', nd 'Tifton 44'. The top three experimentls nd 'Hrdie' produced more first-cut forge thn seven other cultivrs. In the second cutting, 74 X 11-2 gin produced the most. Hrdie nd seven experimentl cultivrs yielded more thn 10 other cultivrs, including three nmed cultivrs. In the third cut, Hrdie nd seven experimentl cultivrs yielded more thn eight other cultivrs. One experimentl tht yielded well in the second cutting, 74 X 12-6, lso rnked highest in cut 3 forge yield, producing more thn 15 other cultivrs. Totl 1994 production ws higher from cultivr 74 X 11-2 thn ny other cultivr. Hrdie nd six experimentls yielded more thn nine other cultivrs. Yields for the 3 yers re shown in Tble 2. Reltive yields of cultivrs vried by yer, s indicted by the significnt (P<.01) yer x cultivr interction. 2 Deprtment of Agronomy, Oklhom Stte University, Stillwter. 36

41 Tble 1. Bermudgrss 1994 Forge Yield, Mound Vlley Unit, Southest Agriculturl Reserch Center Cultivr Spred Cut 1 Cut 2 Cut % moisture b LCB84 X cde 3.35b 1.26bc 1.76bc LCB84 X bcde 3.90b bcd 74 X bcd 2.61def 1.34b 2.18 LCB84 X bcde 2.98bcd 1.05cde 2.02b LCB84 X bcde 3.00bc 0.95def 2.09 Hrdie 1.8def 2.93bcd 1.26bc 1.78bcd LCB84 X bcde 3.07b 1.12cd 1.75cd 74 X g 2.88bcde 1.22bc 1.80bcd LCB84 X bc 3.14b 1.15bcd 1.60def LCB84 X bcde 2.63cdef 1.15bcd 1.96bc LCB84 X bcd 2.84bcde 1.05cde 1.65de LCB84 X bcde 1.11cd 1.34gh Tifton bcde 2.29fg 1.23bce 1.71cde LCB84 X ef 3.09b 0.96def 1.06i LCB84 X bc 2.27fg 0.97def 1.38fg 74 X fg 2.02g 0.89efg 1.70cde Greenfield 3.2b 2.51ef 0.90efg 1.13hi Midlnd 2.8bcd 2.14g 0.78fg 1.48efg LCB84 X cdef 0.70g 0.97i World Feeder 3.2b 2.18gh 0.99f 1.13h Averge LSD(.05) b Visul rting (0-5), where 0 is no spred from originl plnts nd 5 is 100% plot coverge. Mens within column followed by the sme letter re not significntly (P<.05) different, ccording to Duncn's test. 37

42 Tble 2. Bermudgrss Forge Yield, , Mound Vlley Unit, Southest Agriculturl Reserch Center Cultivr Averge % moisture LCB84 X LCB84 X X LCB84 X LCB84 X Hrdie LCB84 X X LCB84 X LCB84 X LCB84 X LCB84 X Tifton LCB84 X LCB84 X X Greenfield Midlnd LCB84 X Averge LSD(.05) Cultivr x yer interction ws significnt (P<.01), so cultivr men comprisons cross yers re not shown. 38

43 LEGUME PERSISTENCE UNDER HAY PRODUCTION MANAGEMENT Joseph L. Moyer Summry Alflf cultivrs selected for grzing vs. hying my differ in longevity in southestern Knss. Four lflfs nd 'Fergus' birdsfoot trefoil were fll-seeded in Cherokee County for comprison of longevity nd productivity. Initil popultions of trefoil were less thn those of lflf cultivrs. All popultions declined to similr levels during the summer of Production of ll cultivrs ws similr by the middle of the first summer. Introduction Soils in southestern Knss re chrcterized by hving slowly permeble subsoils. These soils cn shorten the longevity of stnds of lflf nd other hy-type legumes, prticulrly during wet periods. Alflf cultivrs tht were selected to tolerte grzing by livestock my be longer-lived under some conditions. This test ws designed to compre lflfs tht were selected for different purposes, nd birdsfoot trefoil for persistence nd productivity in southestern Knss. Experimentl Procedures The test ws seeded in prepred seedbed on the Jmes Hefley frm on Tlok silt lom soil in southern Cherokee County on 9 September, Plots 10 x 30 ft were seeded in 10-inch rows t the rte of 12 lb/ for lflfs nd 8 lb/ for Fergus birdsfoot trefoil in rndomized complete block design with three replictions. Two lflfs, ICI 630 nd NK 'Commndor', re hy-producing types. NK 'Spredor II' ws selected for its bility to spred vegettively by root propgtion. 'Alfgrze' ws developed to tolerte grzing pressure. Plots were fertilized preplnt nd on 1 My, 1993 with lb/ of N-P2O5-K2O. No pest control mesures were pplied during the study. Visul rtings of the initil stnds were mde for plots on 21 October, Plnt popultion ws determined by counting crowns within two rndomly chosen 15 x 13-inch res of ech plot. Crowns were counted fter the first cutting in 1992 nd ner the beginning nd end of the 1993 nd 1994 growing sesons. The re ws hyed four times ech in 1992 nd 1994 nd three times in Forge disk meter redings (3/plot) were tken to estimte stnding forge production just prior to cuttings 2, 3, nd 4 in 1992 nd cuttings 1 nd 2 in Results nd Discussion Initil stnd rtings in the first fll were similr for the lflfs, verging 4.4 of possible 5 (dt not shown). However, the stnd of trefoil rted 2.7, significntly lower thn ny lflf. Fll seeding of birdsfoot trefoil did not result in stisfctory stnd before the first winter. Plnt popultions of legume cultivrs over time re indicted by the crown density dt in Fig. 1. Trefoil hd the lowest popultion in the first spring. The only difference in popultion of the lflfs ws tht 630 hd greter stnd density thn Spredor II in the first spring. By 26 months fter seeding, popultions of ll cultivrs 2 hd declined to n verge 1.6 crowns/ft, level tht ws mintined for the next yer. Forge production estimtes were similr for the cultivrs, except for the first mesurement 39

44 (dt not shown). Birdsfoot trefoil produced less forge thn the lflfs in tht first mesurement (cut 2) fter seeding. All cultivrs produced similrly low yields for the lst cut of the first seson becuse of droughty conditions. Production ws highest from cut 1 of the second seson (fourth mesurement) but declined significntly for cut 2. This production decline ws during wetter-thn-norml period in June, 1993 nd just prior to n extremely wet August nd September. During this time the most significnt decline in stnds lso occurred (see Fig. 1). Thus, little difference ws pprent mong the cultivrs in tolernce to wet soil conditions Months fter Plnting 40 Figure 1. Popultions of Four Alflf Cultivrs nd Fergus Birdsfoot Trefoil over Time, Cherokee County, KS. 40

45 NITROGEN RATE AND PLACEMENT EFFECTS ON EASTERN GAMAGRASS UNDER 1-CUT AND 2-CUT HARVEST SYSTEMS Joseph L. Moyer nd Dniel W. Sweeney Summry Estern gmgrss ws fertilized with three nitrogen (N) rtes pplied by brodcst or knife plcement. Hy crops were tken under 1-cut or 2-cut hrvest systems. Forge yield ws incresed under the 2-cut system s compred to 1-cut in 2 of 3 yers. Nitrogen incresed totl yield by 40-45% with the first 45 lb/ increment, nd by n dditionl 14-18% with the next 45-lb increment. Brodcst nd knife N plcements cused no differences in totl sesonl yield or in first-cut yield of either hrvest system. Secondcut yields (2-cut system) were higher (P<.05) from knife compred to brodcst N plcement t higher N rtes in 1992 nd Introduction Estern gmgrss [Tripscum dctyloides (L.) L.] is wrm-seson perennil grss ntive to the North Americn tllgrss pririe. It hs reltively better forge yield potentil nd qulity thn most other wrm-seson ntive species. Estern gmgrss thus my respond well to more intensive mngement prctices such s dded N nd more hrvests. This study ws estblished to determine the response of estern gmgrss to N fertilizer rtes nd plcement under 1-cut or 2- cut hrvest system. Experimentl Procedures Estblished (15-yer-old) 'Pete' estern gmgrss ws burned in April of 3 yers nd fertilized in lte April with 54 lb P2O 5/ nd 61 lb K2O/. Nitrogen (ure-mmonium nitrte solution, 28% N) tretments of 0, 45, or 90 lb/ were pplied in lte April to 8 x 20 ft plots by brodcst or knife (4-inch) plcement. Plots were cut with flil-type hrvester in lte June nd mid August from the 2-cut system nd on bout 10 July from the 1-cut system. Yields were determined from 3 x 20 ft strip of ech plot, with subsmple tken for moisture determintion. Results nd Discussion Totl forge yields for re shown in Tble 1. Totl forge yield ws incresed under the 2-cut system s compred to 1 cut in 1992 nd 1994, but not in Nitrogen incresed totl forge yield in the different yers by 40-45% with the first 45 lb/ increment nd by n dditionl 14-18% with the next 45-lb increment. Similrly, yields from the 1-cut system were incresed 57% (dt not shown), nd first-hrvest yields of the 2-cut system (Fig. 1) were incresed 49% with the first 45-lb/ increment of N. An dditionl 45 lb/ of N incresed yields of those cuttings by 14% nd 18%, respectively. Brodcst nd knife N plcement resulted in no difference in totl sesonl yield (Tble 1) or in first-cut yield of either hrvest system (dt not shown). Second-cut yields (2-cut system) were higher (P<.05) from knife compred to brodcst N plcement in 1992 nd 1993 but not in 1994 (Fig. 2). Significnt interctions between N rte nd plcement occurred in 1992 nd 1993, becuse the plcement response ws found in 1993 t only the 90-lb N rte nd in 1992 t both the 45- nd 90-lb rtes. 41

46 Tble 1. Estern Gmgrss Forge Yields under Two Hrvest Systems with Different Nitrogen Rtes nd Plcement Hrvest Nitrogen Nitrogen Forge Yield System Rte Plcement lb/ tons/cre (12% moisture) Cut 0 Brodcst Knife Brodcst Knife Brodcst Knife Cut 0 Brodcst Knife Brodcst Knife Brodcst Knife LSD(.05) Mens, Nitrogen Plcement Mens, Nitrogen Rte Mens, Hrvest System Brodcst Knife LSD(.05) NS NS NS LSD(.05) Cut Cut LSD(.05) 0.29 NS

47 Nitrogen Rte, lb/ Figure 1. Effect of N Fertiliztion Rte on Forge Yield of Estern Gmgrss under 2-Cut Hrvest System. Nitrogen Rte, lb/ Figure 2. Effect of N Fertiliztion Rte nd Plcement on Forge Yield of the Second Cutting of Estern Gmgrss in 2-Cut System. 43

48 TILLAGE AND NITROGEN FERTILIZATION EFFECTS ON YIELDS IN A GRAIN SORGHUM - SOYBEAN ROTATION Dniel W. Sweeney Summry In 1994, the twelfth cropping yer of grin sorghum-soyben rottion, tillge systems or residul nitrogen (N) fertiliztion did not ffect soyben yields. Introduction Mny kinds of rottionl systems re employed in southestern Knss. This experiment ws designed to determine the longterm effect of selected tillge nd N fertiliztion options on the yields of grin sorghum nd soyben in rottion. Experimentl Procedures A split-plot design with four replictions ws initited in 1983, with tillge systems s whole plots nd N tretments s subplots. The three tillge systems were conventionl, reduced, nd no tillge. The conventionl system consisted of chiseling, discing, nd field cultivtion. The reduced-tillge system consisted of discing nd field cultivtion. Glyphoste (Roundup) ws pplied ech yer t 1.5 qt/ to the no-till res. The four N tretments for the 1983, 1985, 1987, 1989, 1991, nd 1993 grin sorghum were ) no N (check), b) nhydrous mmoni knifed to depth of 6 inches, c) brodcst ure-mmonium nitrte (UAN - 28% N) solution, nd d) brodcst solid ure. N rte ws 125 lb/. Hrvests were collected from ech subplot for both grin sorghum (odd yers) nd soyben (even yers) crops, even though N fertiliztion ws pplied only to grin sorghum. Results nd Discussion Soyben yield in 1994 ws not ffected by tillge or residul fertilizer N (dt not shown). The verge yield ws 42.2 bu/. 44

49 TIMING OF LIMITED-AMOUNT IRRIGATION TO IMPROVE YIELD AND QUALITY OF EARLY-MATURING SOYBEAN Dniel W. Sweeney, Jmes H. Long, nd Mry Beth Kirkhm 1 Summry Limited-mount irrigtion resulted in incresed soyben yield, but bove verge July rinfll my hve msked ny differences cused by irrigtion timing or mount. Protein nd oil contents were not ffected by irrigtion tretments. Introduction Production of erly-mturing soybens my spred economic risk by crop diversifiction. Previous reserch hs shown tht erly-mturing soybens often cn hve yields comprble to those of full-seson soybens. However, one disdvntge of erly-mturing soybens hs been reduced qulity. This potentil for poor qulity my be due to lte reproductive growth tht generlly occurs in July when rinfll is typiclly low. Irrigtion my improve not only yield of erly-mturing soybens, but lso qulity. Even though lrge irrigtion sources such s quifers re lcking in southestern Knss, supplementl irrigtion could be supplied from the substntil number of ponds in the re. Thus, the objective of this study is to determine the effect of timing nd quntity of limited-mount irrigtion for improving yield nd qulity of erly-mturing soybens. Experimentl Procedures The study ws estblished in 1991 on Prsons silt lom soil. The experiment ws split plot rrngement of rndomized complete block design. The min plots comprised 3x2 fctoril rrngement of irrigtion timing nd mount. The three timings were irrigtion t the R4, R5, nd R6 soyben growth stges. The two mounts were 1 nd 2 inches. Also included ws nonirrigted check plot. The subplots were two Mturity Group I soyben cultivrs, 'Hodgson 78' nd 'Weber 84'. Cultivrs were drilled t 200,000 seeds/ on My 10, Results nd Discussion Below verge rinfll in June my hve prtilly reduced yield levels to 22 to 25 bu/ without irrigtion (Tble 1), but bove verge rinfll in July my hve prtilly msked yield response to irrigtion pplied during reproductive growth stges. Irrigtion incresed verge yields of Weber 84 nd Hodgson 78 by pproximtely 7 bu/ bove yields without irrigtion. However, yields were similr regrdless of timing or mount of irrigtion. Protein content of seeds ws slightly higher for Hodgson 78 thn Weber 84, but ws not ffected by irrigtion tretment (Tble 1). Similrly, irrigtion hd little effect on oil content. 1 Deprtment of Agronomy, KSU. 45

50 Tble 1. Effect of Timing of Limited-Amount Irrigtion on Erly-Mturing Soyben Seed Yield nd Qulity Growth Stge Amount Cultivr Yield Protein Oil inches bu/ % R4 1 Hodgson Weber Hodgson Weber R5 1 Hodgson Weber Hodgson Weber R6 1 Hodgson Weber Hodgson Weber Check None Hodgson Weber LSD (0.05) NS NS 0.5 Tretment Mens: Growth Stge R R R LSD (0.05) NS NS NS Amount (inches) LSD (0.05) NS NS NS Cultivr Hodgson Weber LSD (0.05) Interction(s) NS NS NS Contrsts: None vs. ll irrigtion ** NS NS None vs. 1" ** NS NS None vs. 2" ** NS NS 46

51 GRAIN SORGHUM RESPONSE TO LEGUME RESIDUAL AS AFFECTED BY PHOSPHORUS AND POTASSIUM 1 Dniel W. Sweeney, Joseph L. Moyer, nd Dvid A. Whitney 2 Summry Type of legume residul did not ffect the yield of the first grin sorghum crop fter legumes were killed. Phosphorus (P) incresed grin sorghum yields, but potssium (K) did not in Introduction With the ttention recently given to sustinble griculture, interest hs been renewed in the use of legumes in cropping systems. Becuse sustinbility of our griculturl resources needs to coincide with profitbility, chieving nd mintining dequte soil fertility levels re essentil. The residul from legumes such s lflf nd birdsfoot trefoil cn benefit subsequent row crops by supplying nitrogen. However, little informtion is vilble on the importnce of soil P nd K in the residul effect of lflf nd birdsfoot trefoil on subsequent grin sorghum crop. Experimentl Procedures soil test levels hve been mintined in whole plots by fertilizer pplictions. Phosphorus levels t the strt of this study rnged from below 10 to more thn 60 lb/ nd K levels from pproximtely 120 to more thn 200 lb/. The experimentl design ws split-split-plot. The whole plots comprised fctoril rrngement of P nd K rtes. Phosphorus rtes were 0, 40, nd 80 lb PO/, nd K rtes were 0, 125, nd 250 lb 2 5 K O/. Subplots were lflf nd birdsfoot trefoil 2 residul. Sub-subplots were 0 nd 100 lb N/ pplied s ure. Three-yer- old lflf nd birdsfoot trefoil were killed by offset discing on Mrch 22, Grin sorghum ws plnted t 62,000 seeds/ on June 13, Results nd Discussion In 1994, the first crop yer fter lflf nd birdsfoot trefoil were killed, grin sorghum yield ws not ffected by type of legume residul (dt not shown). Mintining the P level with 40 nd 80 lb PO/ 2 5 incresed yield to 119 nd 128 bu/, respectively, from 88 bu/ with no P pplictions. Potssium did not ffect yields in The experiment ws estblished on Prsons silt lom in spring Since 1983, different 1 Reserch prtilly supported by grnt funding from the Knss Fertilizer Reserch Fund. 2 Deprtment of Agronomy, KSU. 47

52 LAND APPLICATION OF COMPOSTED MUNICIPAL SOLID WASTE FOR GRAIN SORGHUM PRODUCTION 1 Dniel W. Sweeney nd Gry Pierzynski 2 Summry Municipl solid wste compost s the only orgnic mendment incresed grin sorghum yield, but ppered to suppress the benefit of cow mnure except t the highest compost rte. Cow mnure nd fertilizer pplictions generlly incresed growth nd yield. Introduction One of the most pressing environmentl issues tht will fce communities in the ner future is solid wste disposl. In recent yers, news medi coverge of lndfill problems hs become common. With diminishing cpcity of existing lndfills nd the reluctnce of the generl populce to crete new lndfills t their own "bck door", other lterntives to stright lndfilling of municipl solid wste (MSW) need to be explored. Incinertion my reduce wste volume, but likely rises s mny environmentl concerns s lndfilling. However, composting of MSW my be more environmentlly cceptble nd should substntilly reduce wste volume. Lndfill longevity could be further extended by finding lterntives to lndfilling the composted MSW. Composted MSW hs potentil uses in griculture, horticulture, silviculture, nd reclmtion. Thus, the objective of this study ws to determine the effect of ppliction rte of composted MSW, with or without cow mnure nd with or without commercil fertilizer, on the growth, composition, nd yield of grin sorghum nd on selected soil chemicl properties. Experimentl Procedures A field study ws estblished in 1992 on Zr silty cly soil t n off-sttion site in Montgomery County. The experimentl design ws split plot rrngement of rndomized complete block with three replictions. The whole plots comprised 4 x 2 fctoril rrngement of four rtes of MSW compost with or without cow mnure. The four rtes of MSW compost were 0 or 4.5, 9, nd 13.5 ton/ pplied ech yer. These rtes were selected to be more in line with "utiliztion" rther thn "disposl" mentlity. The cow mnure rtes were 0 or 4.5 ton/ pplied yerly. The subplots were with or without commercil fertilizer, lb N- PO-K 2 5 2O/. Compost nd cow mnure were pplied on June 2, nd fertilizer ws pplied on June 3. Grin sorghum ws plnted t 62,000 seed/ on June 7. Results nd Discussion Adding MSW compost did not increse dry mtter ccumultion t the 9-lef, boot, or soft dough growth stges s compred with no compost. In contrst, the highest MSW compost ddition resulted in higher grin sorghum yield thn with no compost. However, n interction between MSW compost nd cow mnure suggested tht, lthough compost lone ppered to increse yield, compost seemed to suppress the benefit of cow mnure except t the highest rte of compost ppliction. Adding cow mnure or fertilizer generlly incresed growth nd yield of grin sorghum. 1 With the coopertion of Resource Recovery, Inc. 2 Deprtment of Agronomy, KSU. 48

53 Tble 1. Effect of Composted Municipl Solid Wste (MSW), Cow Mnure (CM), nd Fertilizer on Grin Sorghum Growth nd Yield Dry Mtter Production Tretment 9-Lef Boot Soft Dough Yield lb/ bu/ MSW (t/) LSD 0.05 NS NS NS 5.9 CM (t/) LSD NS 4.1 Fertilizer (lb/) LSD 0.05 NS Interction(s) NS NS NS MxC 49

54 FOLIAR POTASSIUM THIOSULFATE AND BORON FERTILIZATION OF DRYLAND ALFALFA Dniel W. Sweeney nd Joseph L. Moyer Summry Folir pplictions of potssium (K) nd sulfur (S) s potssium thiosulfte nd boron (B) s Solubor did not ffect totl nnul lflf yields in 1993 or Soil pplictions of K, S, nd B t "green-up" produced smll increses in totl lflf production during the 2 yers. Introduction Production of lflf under drylnd conditions requires good mngement of plnt nutrients. Besides requiring fertiliztion with mcronutrients such s phosphorus (P) nd K, lflf nutritionl needs lso include dequte mounts of secondry nutrients nd micronutrients. Dt from previous studies hve indicted tht, in the clypn soils of southestern Knss, lflf my be more responsive to P thn to K fertiliztion. However, in those studies, K concentrtions in the plnt were often low. If soil-pplied K is becoming prtilly unvilble, folir-pplied K my benefit lflf production. Sulfur is secondry nutrient tht my be low in the topsoils of the re, nd fertiliztion with S lso my improve production nd qulity. The current vilbility of potssium thiosulfte (KTS) liquid fertilizer presents the opportunity to pply both K nd S to folige s one compound. Boron is micronutrient tht is importnt for lflf production nd cn be mrginl in the soils of southestern Knss. Applictions of K nd S s KTS nd B s Solubor my provide increses in yield of lflf. Experimentl Procedures The experiment ws conducted on new lflf stnd plnted in fll of 1992 t the Prsons field. The experiment ws 3x2x2 fctoril rrngement. The three rtes of folir KTS supplied i) 0 lb KO/ nd 0 lb S/, ii) 3.0 lb 2 KO/ nd 2.1 lb S/, nd iii) 6.0 lb KO/ nd lb S/. Folir pplictions of B were 0 or 0.5 lb B/. Folir pplictions of KTS nd B were mde when plnts were pproximtely 8 inches tll prior to the first nd second cuttings. Soil pplictions of K, S, nd B were mde t "greenup" to supply 80 lb KO/, 28 lb S/, nd 2 lb 2 B/. Cuttings were tken from 3 x 25 ft re of ech plot. Results nd Discussion During 1993 nd 1994, folir pplictions of KTS or B did not ffect yields (dt not shown). Soil pplictions of K, S, nd B significntly incresed totl nnul yield by 0.4 tons/ (3.8 tons/ without fertiliztion nd 4.2 tons/ with fertiliztion). 50

55 EFFECTS OF PLANTING DATE AND FOLIAR FUNGICIDE ON WINTER WHEAT Kenneth W. Kelley Summry Whet plnted in mid- to lte October produced higher grin yields compred to whet plnted in erly October or in mid-november. Grin yields nd test weights were significntly higher where folir fungicide hd been pplied. Introduction Whet often is plnted over wide rnge of dtes in southestern Knss becuse of the vried cropping rottions. Whet following erly corn, erly grin grin sorghum, or whet is plnted in lte September nd erly October, wheres whet following soybens typiclly is plnted from erly October through erly November. This reserch seeks to determine how plnting dte ffects grin yield of selected hrd nd soft winter whet cultivrs with vrible disese resistnce. Experimentl Procedures In 1994, six winter whet cultivrs were plnted on four different dtes t the Prsons Unit. Cultivrs were selected for vrious folir disese resistnces: 1) modertely resistnt soft whet cultivrs ('Cldwell' nd Pioneer 2551), 2) susceptible hrd whet cultivrs ('Chisholm' nd 'TAM 107'), nd 3) resistnt hrd whet cultivrs ('Krl' nd 2163). Cultivrs were seeded t the recommended rte for ech plnting dte (850,000 seeds/ for erly Oct.; 1,050,000 seeds/ for mid- to lte Oct.; nd 1,250,000 seeds/ for erly Nov. plntings). Tilt, systemic foilr fungicide, ws pplied t 4 oz/ to hlf of the plot re for ech plnting dte when the whet ws t Feekes' growth stge 8 (flg lef just visible from the boot). Results nd Discussion Grin yields nd test weights were highest for the mid- to lte October plnting dtes (Tble 1), but whet plnted in erly October yielded significntly higher thn tht plnted in November. In 1994, folir disese pressure ws reltively light for most of southest Knss; however, t the Prsons Unit, septori lef blotch ws severe ner the criticl whet heding period, which reduced grin yield nd grin qulity. Becuse of the septori disese pressure, grin yield nd test weight were significntly higher for ll cultivrs where Tilt hd been pplied. Whet heding dte ws pproximtely 1 week lter with the lst plnting dte compred to the first (pproximtely 6 weeks prt). 51

56 Tble 1. Effects of Plnting Dte nd Folir Fungicide on Whet Yield nd Test Weight of Selected Cultivrs, Prsons Unit, 1994 Grin Yield Test Weight Heding Plnting Dte Fungicide Fungicide Dte Cultivr No Yes No Yes --- bu/ lb/bu --- Erly October (Oct. 4) My 4 Cldwell (S) My 5 Chisholm My 2 Krl My 3 Pioneer 2551 (S) My 6 TAM My 1 (AVG) Mid-October (Oct. 14) My 6 Cldwell (S) My 7 Chisholm My 4 Krl My 5 Pioneer 2551 (S) My 8 TAM My 3 (AVG) Lte October (Oct. 28) My 8 Cldwell (S) My 9 Chisholm My 5 Krl My 6 Pioneer 2551 (S) My 11 TAM My 5 (AVG) Erly November (Nov. 10) My 11 Cldwell (S) My 12 Chisholm My 10 Krl My 10 Pioneer 2551 (S) My 14 TAM My 9 (AVG) LSD (0.05): Cultivr within sme (F) & sme (DOP) Cultivr for different (F) & sme (DOP) S = soft whet cultivr. Folir fungicide = Tilt, pplied t 4 oz/ t Feekes' GS 8 (erly boot stge). 52

57 WHEAT AND SOYBEAN ROTATIONS COMPARED Kenneth W. Kelley Summry Full-seson soybens hve verged 5 bu/ higher yields thn double-crop soybens over the 14-yer period. Full-seson soyben yield lso hs been highest where no double-cropping occurred in the previous yer. Since 1988, whet yield hs been 10 bu/ higher following whet compred to whet following lte-mturing soybens (MG 4 nd 5), wheres whet yield following erly-mturing soybens (MG 1 nd 3) hs been nerly the sme s whet yield following whet. Introduction In southestern Knss, producers often rotte whet fter soybens or plnt double-crop soybens following whet hrvest. Mngement prctices of one crop, therefore, my ffect the production of the subsequent crop. This reserch seeks to determine the long-term effects of whet nd soyben rottions on yield nd soil properties. Experimentl Procedures Beginning in 1981, three different whet nd soyben rottions were estblished t the Prsons Unit: 1) [continuous whet - double-crop soybens, 2) [whet - double-crop soyben] - fullseson soyben, nd 3) full-seson soyben following whet with no double-cropping. Prior to 1988, full-seson soybens were mturity group (MG) V nd double-crop, MG III or IV. Beginning in 1988, MG I, III, IV, nd V were compred in both full-seson nd double-crop rottions (Rottion # 2). Group I mturity ws plnted in erly My in 7-inch row spcing, wheres the other full-seson mturity groups normlly were plnted in lte My or erly to mid-june. Double-crop soybens were plnted in lte June or erly July fter whet. In 1994, dditionl cultivrs with vrying resistnce to soyben cyst nemtode (SCN) were included. Prior to 1988, whet ws plnted fter ll doublecrop nd full-seson soybens hd mtured, regrdless of rottion. However, since 1988, whet hs been plnted t different times with respect to individul crop rottions. Results nd Discussion Tble 1 shows the yerly soyben yields for the different whet nd soyben rottions for the pst 14 yers. Double-crop soyben yields hve verged nerly 20 bu/, with no difference in yield from continuous double-cropping versus double-cropping every other yer. Full-seson soyben yields following summer-fllowed whet hve verged 2 bu/ higher thn those following double-crop soybens. Full-seson soyben yields hve verged 5 to 7 bu/ higher thn double-crop soyben yields, but the vrition from yer to yer hs been significnt. During the yers when wet wether conditions delyed full-seson plnting (1982, 1985, 1989, nd 1992) until the sme time s double-crop plnting, no significnt differences occurred in yields mong rottions. Since 1988, soyben mturity hs significntly influenced full-seson soyben yield, but when verged over 7 yers, grin yield differences between mturity groups were less thn 2 bu/ (Tble 2). In double-crop systems (Tble 3), MG IV hs consistently produced the highest yield. In 1994, growing conditions were excellent for both double-crop nd full-seson soyben (Tble 4). Although significnt yield differences occurred in grin yield between 53

58 mturity groups, results suggest tht the SCN is not problem t this site. Whet yield s ffected by the different crop rottions is shown in Tble 4. Yield differences hve been more pronounced since whet hs been plnted t different dtes ccording to the prticulr rottion scheme. Since 1988, whet yields hve verged 10 bu/ higher following whet compred to whet following full-seson soybens. Whet following 2 yers of soybens (double-crop nd full-seson) hs yielded nerly the sme s whet following only 1 yer of fullseson soybens. Whet yields hve been lowest in the continuous double-crop system. Whet plnted fter erly-mturing soybens (MG I) hs yielded nerly the sme s whet fter whet, wheres whet yields hve been lowest following lte-mturing soybens (MG V). Tble 1. Effects of Whet nd Soyben Cropping Systems on Soyben Yield, Southest Agriculturl Reserch Center, Prsons, KS Crop (Rot. 1) (Rot. 2) (Rot. 2) (Rot. 3) Yer Wh - DC Soy Wh - DC Soy Wh - DC Soy Wh - Wh LSD FS Soy FS Soy FS Soy (0.05) bu/ * NS NS * NS * * Avg (*) Full-seson nd double-crop soybens were plnted on the sme dtes in 1982, 1985, 1989, nd DC = Double-crop soybens; FS = full-seson soybens. Cultivrs plnted: Double-crop (MG IV); full-seson (MG V). 54

59 Tble 2. Comprison of Soyben Mturity Groups in Full-Seson Soyben Crop Rottion, Southest Agriculturl Reserch Center, Prsons, KS Mturity Full-Seson Soyben Yield Group Cultivr Avg bu/ I Weber III Flyer IV Stfford V Hutcheson LSD (0.05) Rottion is [Whet - double-crop soyben] - full-seson soyben. Tble 3. Comprison of Soyben Mturity Groups in Double-Crop Soyben Crop Rottion, Southest Agriculturl Reserch Center, Prsons, KS Mturity Double-Crop Soyben Yield Group Cultivr Avg bu/ I Weber III Flyer IV Stfford V Essex LSD (0.05) Rottion is [Whet - double-crop soyben] - full-seson soyben. 55

60 Tble 4. Comprison of Soyben Cultivrs with Vrying Mturity nd SCN Resistnce in Full- Seson nd Double-Crop Rottions, Southest Agriculturl Reserch Center, 1994, Prsons, KS Mturity SCN Soyben Yield Plnt Mturity Cultivr Group Resistnce Full- Double- Full- Double- Seson Crop Seson Crop bu/ bu/ Weber I No Aug 24 Sept 30 Jck II Yes Sept 5 Oct 10 Flyer III No Sept 30 Oct 10 Del-Soy 4210 III Yes Sept 30 Oct 10 Stfford IV No Oct 10 Oct 24 Mnokin IV Yes Oct 11 Oct 25 Hutcheson V No Oct 15 Oct V Yes Oct 19 Oct 28 LSD (0.05): SCN hs not been detected t this site. Rottion is [Whet - double-crop soyben] - full-seson soyben. 56

61 Tble 5. Effect of Whet nd Soyben Cropping Rottions on Whet Yield, Southest KS Agriculturl Reserch Center, Prsons, KS (Rot. 1) (Rot. 2) (Rot. 3) (Rot. 3) Yer (Wh-DC Soy) (Wh-DC Soy) Whet Whet FS Soy Whet Whet LSD FS Soy FS Soy (0.05) bu/ yr vg yr vg Whet ws not hrvested from 1985 through 1987 becuse of wet soil conditions. Spring ots were plnted in 1986 nd 1987 s substitute crop for whet. Soyben mturity group: Rottion 1: MG III or MG IV Rottion 2 & 3: MG V From , whet for ll rottions ws plnted on the sme dte, which ws fter the ltest mturing soybens. Since 1988, whet hs been plnted t different times ccording to the prticulr cropping system. 57

62 Tble 6. Effects of Soyben Mturity Group on Whet Yield, Southest KS Agriculturl Reserch Center, Prsons Unit Soyben Whet Yield Mturity Avg bu/ MG I MG III MG IV MG V LSD (0.05) Crop rottion: [Whet - double-crop soy] - full-seson soybens Plnting dtes: 1989: Oct. 14, 1988 (MG I, III, & IV) Oct. 25, 1988 (MG V) 1990: Oct. 16, 1989 (MG I & III) Oct. 27, 1989 (MG IV & V) 1991: Oct. 5, 1990 (MG I & III) Oct. 16, 1990 (MG IV & V) 1992: Oct. 7, 1991 (MG I, III, & IV) Oct. 23, 1991 (MG V) 1993: Oct. 14, 1992 (MG I & III) Nov. 2, 1992 (MG IV & V) 1994: Oct. 11, 1993 (MG I & III) Oct. 28, 1993 (MG 4 & 5) 58

63 LONG-TERM EFFECTS OF CROPPING SYSTEMS ON SOYBEAN YIELDS Kenneth W. Kelley Summry In the bsence of soyben cyst nemtode (SCN), continuous soybens hve yielded nerly 10% less thn soybens grown in 2-yr rottion following double-crop soybens, grin sorghum, or fllowed whet. However, in the presence of SCN, soyben yield hs declined nerly 25% in the monoculture soyben system. Introduction Soyben is mjor crop for frmers in southestern Knss. Typiclly, soybens re grown in severl cropping sequences with whet, grin sorghum, nd corn or in double-cropping rottion with whet. However, soybens cn follow soybens, if producer elects to enter the federl frm progrm nd does not hve lrge enough whet nd feed-grin bse to permit dequte crop rottion of vilble crop crege. With the recent rrivl of soyben cyst nemtode (SCN) into extreme southestern Knss, more informtion is needed to determine how crop rottions cn be used to mnge round the nemtode problem. Experimentl Procedures In 1979, four cropping systems were strted t the Columbus Unit: 1) [whet - double-crop soyben] - soybens, 2) [whet - summer fllow] - soybens, 3) grin sorghum - soybens, nd 4) continuous soybens. Full-seson soybens were compred cross ll rottions in even-numbered yers. Beginning in 1984, n identicl study ws strted djcent to the initil site, so tht fullseson soybens lso could be compred in oddnumbered yers. All rottions received the sme mount of phosphorus nd potssium fertilizers (80 lb/ ech), which were pplied to the crop preceeding full-seson soybens. Beginning in 1991, n SCN-susceptible nd n SCN-resistnt cultivr were compred within ech of the four cropping systems. In 1994, dditionl cultivrs with vrying resistnce to SCN were included in the rottion. During lternte yers, susceptible cultivr is plnted in full-seson nd double-crop rottions. Results nd Discussion Soyben yields from the initil study (no SCN) from 1980 through 1992 re shown in Tble 1, with the 1994 results shown in Tble 2. Continuous soybens hve yielded 10% less thn soybens grown in rottion. However, in the continous soybens, yield hs not been depressed s much s nticipted, considering tht soybens hve been grown continuously on tht site for the pst 14 yers. Soybens yields from the djcent study tht ws strted in 1984 re shown in Tble 3. At this site, SCN were detected in 1989, nd soyben yield hs been reduced nerly 25% in the continuous soyben rottion. Soyben yield differences between resistnt (5292) nd susceptible (Stfford) cultivrs hve not been s pronounced s in other SCN reserch sites in Cherokee County. It is uncler why the yield response hs been different t this SCN site; however, soil nlyses of SCN popultions re not completed t this time. 59

64 Tble 1. Effect of Long-Term Cropping Systems on Soyben Yield in the Absence of SCN, Southest KS Agriculturl Reserch Center, Columbus Unit Full-Seson Soyben Following 1 Yr Wh - DC Soy Gr Sorg Whet Soy LSD bu/ NS NS Avg Lespedez ws grown in the summer fllow period from Tble 2. Comprison of Soyben Cultivrs with Vrying Mturity nd SCN Resistnce in Four Crop Rottions in the Absence of SCN, Columbus Unit, 1994 Full-Seson Soyben Following Cultivr Mturity SCN Whet Grin Whet Cont. Avg. Group Resist. DC Soy Sorgh Fllow Soy bu/ Jck II Yes Shermn III No Flyer III No DelSoy 4210 IV Yes Stfford IV No Mnokin IV Yes Hutcheson V No Forrest V Yes Avg LSD 0.05: Compring cultivrs within sme crop rottion: Compring mens of different crop rottions: 5.7 Compring mens of soyben cultivrs:

65 Tble 3. Effects of Long-Term Cropping Systems on Soyben Yield in the Presence of Soyben Cyst Nemtode, Columbus Unit Full-Seson Soyben Following 1 Yr - Cultivr DC Soy Gr Sorgh Whet Soy LSD bu/ SCN-Susceptible SCN-Susceptible SCN-Susceptible SCN-Resistnt SCN-Susceptible SCN-Resistnt SCN-Susceptible Avg - SCN-S Beginning in 1991, plots were split to include n SCN-resistnt cultivr (5292) nd n SCN-susceptible cultivr (Stfford). 61

66 SOYBEAN HERBICIDE RESEARCH 3 Kenneth W. Kelley Summry Vrious soyben herbicide tretments nd ppliction methods were compred for weed control in no-tillge nd conventionl-tillge conditions. Weed control generlly ws good to excellent in both tillge systems. Introduction Soybens occupy pproximtely 40% of the crop crege in southestern Knss. Herbicide studies re conducted to compre herbicide performnce nd ppliction methods for the control of nnul brodlef nd grssy weeds in soybens. Becuse of the interest in conservtion tillge prctices, severl studies evluted herbicide performnce in no-till conditions s well s with conventionl tillge. Experimentl Procedures Soyben herbicide trils were conducted t the Columbus Unit nd t n off-sttion site in Cherokee County. Soybens were grown in 30- inch row spcing. All tretments were pplied with trctor-mounted, compressed ir spryer, with spry volume of 20 GPA. Plot size ws 4 rows wide by 30 ft in length, with three replictions. The center two rows of ech plot were hrvested for yield. Preplnt tretments were incorported with field cultivtor, equipped with three-br tine mulcher. Weed rtings were tken on 20 July. Herbicides, ppliction methods, nd times of ppliction were compred t site in Cherokee County tht ws infected hevily with soyben cyst nemtode (SCN). The objective ws to evlute effects of different modes of ction on soyben crop injury nd subsequent weed weed control in the presence of SCN. Results nd Discussion No Tillge Results of three herbicide trils with no tillge re shown in Tbles 1, 2, nd 3. Soybens were plnted no-till into stnding grin sorghum stubble tht hd been rotry mowed. Weed control nd soyben yields were good to excellent. Erly preplnt pplictions of Roundup nd 2,4-D,LVE (low-voltile ester) gve excellent burn-down weed control. When residul brodlef herbicides (Cnopy, Scepter, Brodstrike) were dded to erly burn-down tretments, weed control generlly ws good to excellent, except where hevy cocklebur popultions existed. In those cses, postemergent brodlef herbicide ppliction ws needed to supplement the erly residul pplictions. However, in 1994, dry soil conditions during lte June resulted in less effective postemergent weed control thn in prior yers. Adding crop oil concentrte (1 qt/) to postemergent herbicide pplictions gve better brodlef weed control thn nonionic surfctnt. Erly burn-down pplictions of Roundup nd 2,4-D,LVE followed by residul herbicide tretments pplied either preplnt or preemergent fter plnting lso provided good weed control. Wet soil conditions ner soyben mturity delyed hrvest; however, hrvest delys were miniml on no-till plots becuse of firmer soil conditions. SCN-Infected Site Grin yield nd weed control results for the SCN site re shown in Tble 4. In 1994, soils were wrmer thn norml when erly preplnt 3 Products without lbel registrtion re mentioned for informtionl purposes only nd re not recommended for use. 62

67 herbicide tretments were pplied in erly My, which my hve reduced possible herbicide crop injury effects. Rinfll shortly fter plnting ctivted preemergent herbicide tretments; however weed control ws less thn idel for postemergent herbicide tretments becuse of dry soil conditions in lte June. Grin yields vried mong herbicide tretments, lthough yields ppered to be influenced more by degree of weed control thn time of ppliction. This study will be conducted gin in 1995 t the sme site to further evlute soyben response to different herbicide modes of ction. Soyben plnts infected with SCN often show reduced root growth. Dinitroniline herbicides lso hve been shown to inhibit erly soyben root growth on some light-textured soils; thus, root growth might be ffected even more where dinitro-niline herbicide tnkmixes re pplied preplnt in SCNinfected soils. Conventionl Tillge Erly preplnt nd preplnt herbicide results re shown in Tble 5. Brodlef nd grss weed control ws good to excellent for nerly ll tretments, lthough herbicides pplied immeditely hed of plnting gve slightly better weed control thn those pplied 4 weeks erlier. Postemergent herbicide results re shown in Tble 6; nerly ll tretments gve good to excellent brodlef weed control. Crop injury rtings fter herbicide pplictions vried gretly mong tretments. However, even where crop injury ws rther severe initilly fter herbicide ppliction, soyben plnts resumed norml growth within few dys. Conventionlly tilled herbicide plots t the Columbus Unit were not hrvested for grin yield becuse of extremely wet soil conditions in October nd November. 63

68 Tble 1. Comprison of Herbicides for Soybens Plnted No-Till, Tril 1, Columbus Unit Weed Control Trt Time Herbicide Rte Yield WA BL GR Product/ bu/ % % % 1 EPP Roundup + 2,4-DE 1 pt + 1 pt PP Cnopy + crop oil 6 oz + 1 qt PO Assure II + crop oil 8 oz + 1 qt 2 EPP Cnopy + 2,4-DE 6 oz + 1 pt EPP Crop oil 1 qt PP Roundup 1 pt PO Bsgrn + crop oil 1 pt + 1 qt PO Assure II + crop oil 8 oz + 1 qt 3 EPP Scepter + 2,4-DE 2.8 oz + 1 pt EPP Crop oil 1 qt PP Roundup 1 pt PO Select + crop oil 8 oz + 1 qt 4 EPP Roundup + Cnopy 1 pt + 6 oz PO Clssic + crop oil 0.5 oz + 1 qt PO Assure II + crop oil 8 oz + 1 qt 5 EPP Roundup + Scepter 1 pt oz PO Select + crop oil 8 oz + 1 qt 6 EPP Roundup 1 pt PP Roundup 1 pt PO Bsgrn + crop oil 1.5 pt + 1 qt PO Post (+) + crop oil 1.5 pt + 1 qt 7 PP Roundup 1.5 pt PP Cnopy + Dul 6 oz pt 8 PP Roundup 1.5 pt PP Squdron 3 pt 9 PP Roundup 1.5 pt PP Brodstrike + Dul 2.25 pt PO Bsgrn + crop oil 1 pt + 1 qt 10 PP Roundup 1.5 pt PP Lsso + Sencor 2 qt + 8 oz PO Bsgrn + NIS 1 pt % 64

69 Tble 1. Continued Weed Control Trt Time Herbicide Rte Yield WA BL GR Product/ bu/ % % % 11 PP Roundup + 2,4-DE 1.5 pt + 1 pt PRE Dul + Cnopy 1.5 pt + 5 oz 12 PP Roundup + 2,4-DE 1.5 pt + 1 pt PRE Squdron 3 pt 13 PP Roundup + 2,4-DE 1.5 pt + 1 pt PP Dul + Brodstrike 2.25 pt PO Bsgrn + crop oil 1 pt + 1 qt 14 PP Roundup + 2,4-DE 1.5 pt + 1 pt PRE Lsso + Sencor 2 qt oz PO Bsgrn + NIS 1 pt % 15 PP Roundup + 2,4-DE 1.5 pt + 1 pt PO Clssic + NIS 0.5 oz % PO Assure II + crop oil 8 oz + 1 qt 16 PP Roundup + 2,4-DE 1.5 pt + 1 pt PP Prowl 2.4 pt PO Scepter + NIS 1.4 oz % 17 PP Roundup + 2,4-DE 1.5 pt + 1 pt PO Bsgrn + NIS 1 pt % PO Post (+) + Dsh 1.5 pt + 1 qt 18 PP Roundup + 2,4-DE 1.5 pt + 1 pt PO Pursuit + N + COC 2 oz + 1 qt + 1 qt PO Select + crop oil 6 oz + 1 qt 19 PP Roundup + 2,4-DE 1.5 pt + 1 pt PO Cobr + NIS 12 oz % PO Select + crop oil 8 oz + 1 qt No herbicide LSD: (0.05) EPP = erly preplnt (5/12), PP = preplnt (5/24), PRE = preemergent (6/7), PO = postemergent (6/28) nd (7/6). Weed rting July 20. WA = winter nnuls (Crolin foxtil, shepherdspurse, smllflowered bittercress, bushywllflower), BL = cocklebur, GR = crbgrss. 65

70 Tble 2. Comprison of Herbicides nd Time of Appliction for Soybens Plnted No-Till, Tril 2, Columbus Unit Weed Control Trt Time Herbicide Rte Yield WA BL GR Product/ bu/ % % % 1 EPP Roundup 1.5 pt EPP Pursuit Plus 2.5 pt PO Bsgrn + Cobr 1 pt + 6 oz PO Crop oil + 28% N 1 qt + 1 qt 2 EPP Roundup 1.5 pt EPP Lsso + Cnopy 2 qt + 5 oz 3 EPP Roundup 1.5 pt EPP Squdron + Commnd 3 pt + 4 oz 4 EPP Roundup 1.5 pt EPP Dul + Brodstrike 2.25 pt PO Bsgrn 1.5 pt PO Crop oil + 28% N 1 qt + 1 qt 5 EPP Roundup 1.5 pt EPP Lsso + Sencor 2 qt + 8 oz PO Bsgrn + NIS 1 pt % 6 EPP Cnopy + Commnd 5 oz + 1 pt EPP Crop oil 1 qt PO Assure + crop oil 8 oz + 1 qt 7 PP Roundup 1.5 pt PRE Pursuit Plus 2.5 pt PRE Sun-it II 1.5 pt 8 PP Roundup 1.5 pt PRE Lsso + Cnopy 1.5 qt + 5 oz PRE Sun-it II 1.5 pt 9 PP Roundup 1.5 pt PRE Squdron 3 pt PRE Sun-it II 1.5 pt 10 PP Roundup 1.5 pt PRE Dul + Brodstrike 2.25 pt 66

71 Tble 2. Continued Weed Control Trt Time Herbicide Rte Yield WA BL GR Product/ bu/ % % % 11 PP Roundup 1.5 pt PRE Lsso + Sencor 2 qt + 6 oz PRE Crop oil 1 qt PO Bsgrn + Cobr 1 pt + 6 oz PO Crop oil + 28% N 1 qt + 1 qt 12 PP Roundup + 2,4-DE 1.5 pt + 1 pt PO Bsgrn + Blzer 1 pt + 1 pt PO NIS + 28% N 0.25 % + 1 qt PO Post (+) + Dsh 1.5 pt + 1 qt PO Cobr + 2,4-DB 8 oz + 3 oz 13 PP Roundup + 2,4-DE 1.5 pt + 1 pt PO Clssic + Pinncle 0.5 oz oz PO NIS + 28% N 0.125% + 1 qt PO Assure II + crop oil 8 oz + 1 qt 14 PP Roundup + 2,4-DE 1.5 pt + 1 pt PO Pursuit + Cobr 3 oz + 3 oz PO NIS + 28% N 0.25% + 1 qt PO Select + crop oil 8 oz + 1 qt No herbicide LSD: (0.05) EPP = erly preplnt (5/12), PP = preplnt (5/24), PRE = preemergent (6/7), PO = postemergent (6/28) nd (7/6). Weed rting July 20. WA = winter nnuls (Crolin foxtil, shepherdspurse, smllflowered bittercress, bushywllflower), BL = velvetlef nd cocklebur, GR = crbgrss. 67

72 Tble 3. Comprison of Herbicides nd Time of Appliction for Soybens Plnted No-Till, Tril 3, Columbus Unit Weed Control Trt Time Herbicide Rte Yield WA BL GR Product/ bu/ % % % 1 EPP Roundup + 2,4-DE 1 pt + 1 pt PP Cnopy + crop oil 6 oz + 1 qt * PO Clssic + 2,4-DB 0.5 oz + 2 oz PO Assure + crop oil 8 oz + 1 qt 2 EPP Cnopy + 2,4-DE 6 oz + 1 pt EPP Crop oil 1 qt PO Clssic + crop oil 0.5 oz + 1 qt PO Assure + crop oil 8 oz + 1 qt 3 PP Roundup 1.5 pt PP Cnopy 6 oz PP Dul 1.5 pt * PO Clssic + 2,4-DB 0.5 oz + 2 oz 4 PP Roundup 1.5 pt PP Squdron 3 pt 5 PP Roundup 1.5 pt PP Brodstrike + Dul 2.25 pts PO Bsgrn + crop oil 1.5 pt + 1 qt 6 PP Roundup + Sencor 1.5 pt + 8 oz PP Lsso 2 qt PO Bsgrn + Blzer 1 pt + 1 pt PO Crop oil 1 pt 7 PP Roundup + 2,4-DE 1.5 pt + 1 pt * PO Clssic + Cobr 0.5 oz + 3 oz PO Assure + crop oil 8 oz + 1 qt 8 PP Roundup + 2,4-DE 1.5 pt + 1 pt * PO Scepter + Cobr 1.4 oz + 3 oz 9 PP Roundup + 2,4-DE 1.5 pt + 1 pt * PO Pursuit + Cobr 3 oz + 3 oz 68

73 Tble 3. Continued Weed Control Trt Time Herbicide Rte Yield WA BL GR Product/ bu/ % % % 10 PP Roundup + 2,4-DE 1.5 pt + 1 pt * PO Bsgrn + Cobr 1 pt + 3 oz PO Post (+) + crop oil 1.5 pt + 1 qt No herbicide LSD: (0.05) NS 6 7 (*) Nonionic surfctnt (0.25% v/v) dded to postemergent tretments. EPP = erly preplnt (5/12), PP = preplnt (5/24), PO = postemergent (6/28) nd (7/6). WA = winter nnuls (Crolin foxtil, shepherdspurse, smllflowered bittercress, bushy wllflower), BL = cocklebur nd smooth pigweed, GR = crbrss. Weed rting July

74 Tble 4. Effects of Herbicides nd Time of Appliction on Soyben Yield nd Weed Control on Soil Infected with Soyben Cyst Nemtode, Cherokee County Weed Control Trt Time Herbicide Rte Yield BL GR Product/ bu/ % % 1 EPP Squdron 3 pt EPP Trefln 1.5 pt EPP Cnopy 6 oz 3 EPP Trefln 2 pt EPP Brodstrike 4 EPP Trefln 1.5 pt PO Bsgrn 0.75 pt PO Blzer 0.75 pt PO NIS 0.25% 5 PP Squdron 3 pt PP Trefln 1.5 pt PP Cnopy 6 oz 7 PP Trefln 2 pt PP Brodstrike 8 PP Trefln 1.5 pt PP Sencor 6 oz PO Bsgrn 1 pt PO NIS 0.25% 9 PP Lsso 2 qt PP Scepter 2.8 oz 10 PP Lsso 2 qt PP Cnopy 6 oz 11 PP Dul 2.25 pt PP Brodstrike 12 PP Dul 1.5 pt PP Sencor 6 oz PO Bsgrn 1 pt PO NIS 0.25% 70

75 Tble 4. Continued Weed Control Trt Time Herbicide Rte Yield BL GR Product/ bu/ % % 13 PP Prowl 2.4 pt PO Scepter 1.4 oz PO Cobr 6 oz PO NIS 0.25% 14 PP Lsso 2 qt PO Clssic 0.5 oz PO Cobr 6 oz PO NIS 0.25% 15 PRE Lsso 2 qt PRE Scepter 2.8 oz 16 PRE Lsso 2 qt PRE Cnopy 5 oz 17 PRE Dul 2.25 pt PRE Brodstrike 18 PRE Dul 1.5 pt PRE Sencor 5.33 oz PO Bsgrn 1 pt PO NIS 0.25% 19 Weed free No herbicide LSD: (0.05) EPP = erly preplnt incorported (5/23), PP = preplnt incorported (6/7), PRE = preemergent (6/7), PO = postemergent (6/28). BL = cocklebur nd smooth pigweed, GR = nnul crbgrss. Weed rting July

76 Tble 5. Comprison of Erly Preplnt nd Preplnt Herbicides for Conventionlly Tilled Soybens, Columbus Unit Weed Control Trt Time Herbicide Rte BL GR Product/ % % 1 EPP Squdron 3 pt EPP Tri-Scept 2.33 pt EPP Freedon + Scepter 3 pt oz EPP Trefln + Brodstrike 2 pt EPP Dul + Brodstrike 2.25 pt EPP Trefln + Cnopy 1.5 pt + 6 oz PP Squdron 3 pt PP Tri-Scept 2.33 pt PP Freedom + Scepter 3 pt oz PP Trefln + Brodstrike 2 pt PP Dul + Brodstrike 2.25 pt PP Trefln + Cnopy 1.5 pt + 6 oz No herbicide 0 0 LSD: (0.05) 6 NS EPP = erly preplnt incorported (5/12), PP = preplnt incorported (6/13). BL = cocklebur, GR = crbgrss. Weed rting July

77 Tble 6. Comprison of Postemergent Herbicides for Conventionlly Tilled Soybens, Columbus Unit Brodlef Crop Trt Time Herbicide Rte Weed Control Injury Product/ % 1 PRE Prowl 2.4 pt PO Scepter 1.4 oz PO NIS + 28% N 0.25% + 1 qt 2 PRE Prowl 2.4 pt PO Clssic 0.5 oz PO NIS + 28% N 0.25% + 1 qt 3 PRE Prowl 2.4 pt PO Clssic + Pinncle 0.25 oz oz PO NIS + 28% N % + 1 qt 4 PRE Prowl 2.4 pt PO Storm 1.5 pt PO NIS + 28% N 0.25% + 1 qt 5 PRE Prowl 2.4 pt PO Cobr 12 oz PO NIS + 28% N 0.25% + 1 qt 6 PRE Prowl 2.4 pt PO Pursuit 4 oz PO NIS + 28% N 0.25% + 1 qt 7 PO Scepter 1.4 oz PO Select + crop oil 7 oz + 1 qt 8 PO Pursuit 4 oz PO Select 4 oz PO Crop oil + 28% N 1 qt + 1 qt 9 PO Cobr 8 oz PO Select 6 oz PO Crop oil + 28% N 1 qt + 1 qt 10 PO Scepter 1.4 oz PO Cobr 6 oz PO Select 6 oz PO Crop oil + 28% N 1 pt + 1 qt 73

78 Tble 6. Continued Brodlef Crop Trt Time Herbicide Rte Weed Control Injury Product/ % 11 PO Pursuit 4oz PO Cobr 4 oz PO Select 6 oz PO Crop oil + 28% N 1 pt + 1 qt 12 PO Storm 1.5 pt PO Post Plus 1.5 pt PO Crop oil + 28% N 1 qt + 1 qt 13 PO Clssic + Pinncle 0.25 oz oz PO Assure II 8 oz PO Crop oil + 28% N 1 pt + 1 qt 14 No herbicide LSD: (0.05) PRE = preemergent (6/12), PO = postemergent (7/6). BL = cocklebur nd smooth pigweed. CI = crop injury rting for postemergent herbicide tretments = 1 no injury nd 5 = severe lef chlorosis. Weed rting July

79 SOYBEAN VARIETY TRIAL FOR CYST NEMATODE RESISTANCE Jmes H. Long, Willim T. Schpugh, Ted Wry, nd Timothy Todd Summry Soybens vrieties with resistnce to cyst nemtodes hve prevented s much s 50 % of grin yield loss over vrieties without such resistnce in Cherokee County, Knss since Severe drought occurred in 1991, wheres 1992, 1993 nd 1994 were wet yers. Severl vrieties in both Mturity Groups IV nd V hd very good yield potentil nd dequte resistnce to soyben cyst nemtode. These could be used in suitble rottions to combt the pest. Introduction The ppernce of soyben cyst nemtode in Southestern Knss hs complicted the production of soybens by requiring definite pln to combt the pest. Prt of this plnning is to use vrieties tht re resistnt to the nemtode. Ongoing trils to identify dpted resistnt vrieties were estblished in n re of the southest region, Cherokee County, known to hve dmging popultions of the pest. Experimentl Procedures Forty one vrieties of soybens, some rted s resistnt to cyst nemtode, were plnted on June 10, This tril ws grown t the Cyst Nemtode Reserch Are locted on the Mrtin Frms in Columbus. Seed were plnted t 8 per row foot in 30-inch rows. Fertilizer ppliction included 290 lb/ of before plnting in Mturities were rted in September nd October, nd plots were hrvested with plot combine on October 28, Test weight nd seed moisture were mesured with Dickey-John nlyzer, nd grin yields were djusted to 13 % moisture. Results nd Discussion Vrieties with resistnce to soyben cyst nemtode prevented yield losses of 40 % or more during the yers (Tble 1). Resistnt vrieties such s 'Mnokin', nd 'Pioneer 9521' verged yields of pproximtely 34 bu/ over the 4-yer period. Susceptible vrieties of similr mturity such s 'Essex' hd verge yields of only 20 bu/ during the sme period. Soyben mturity grouping lso my hve plyed role in grin yield. Over 3-yer period, susceptible vrieties such s mturity group V 'Hutcheson' verged yields of 26.1 bu/, wheres the erlier mturing, lte group IV 'Stfford' verged yields of only 23.0 bu/ nd the erly group IV 'Flyer' verged 18.3 bu/ (Tble 1). More vriety test informtion cn be found in Report of Progress 723, 1994 Knss Performnce Tests with Soyben Vrieties. 1Deprtment of Agronomy, KSU. 2 Formerly Cherokee County Agriculturl Extension Agent. 3 Deprtment of Plnt Pthology, KSU. 75

80 Tble 1. Grin Yield of Cyst Nemtode-Resistnt nd-susceptible Soyben Vrieties t the Wilkinson nd Mrtin Frms, 1994 nd Summries Grin Yield Averge Yield Brnd Vriety 2 MG yr 3-yr 4-yr bu/ Asgrow A4715 IV Asgrow A5112 V Deklb CX469C IV Delnge DS 464 IV Hyperformer HY458 IV Hyperformer HSC501 V Merschmn Houston III IV Midlnd XP452 IV Midlnd 8475 IV NC+ 4A27 IV NC+ 5A15 V Northrup S46-44 IV King S52-25 V Pioneer 9491 IV Pioneer 9521 V Ohlde 4120N IV Ohlde 4262N IV Ohlde 4440 IV Ohlde 5020N V Ohlde 5200N V Stine 4322CN IV Terr E4292 IV Terr E461 IV Terr E4792 IV Terr E474 IV Willcross 9447-A IV Willcross 9447-B IV Public Flyer IV Public Stfford IV Public Essex V Public Holldy V Public Hutcheson V Public Avery IV/V Public Delsoy 4210 IV Public Delsoy 4500 IV Public Delsoy 4710 IV Public Delsoy 4900 IV Public Mnokin IV/V Public Forrest V Public Hrtwig V Public KS 5292 V Averge L.S.D. (0.05)

81 PERFORMANCE TRIAL OF DOUBLE-CROP SOYBEAN VARIETIES Jmes H. Long nd Gry L. Kilgore 1 Summry Twenty double-crop soyben vrieties were plnted following winter whet in Columbus, Knss nd evluted for yield nd other gronomic chrcteristics throughout the summer of Grin yields were good, nd vriety differences were seen under the fvorble growing conditions. Yields rnged from 18 bu/ to ner 30 bu/. The short-seson MG (mturity group) III nd IV vrieties mtured during the first week of October, wheres long-seson vrieties in MG V mtured s much s 3 weeks lter. Generlly, the longer the MG, the higher the pod set. 'Avery' nd 'Mnokin' mtured in lte October nd set first pods higher thn other vrieties mturing t the sme time. Introduction Double-cropped soyben is n opportunistic crop grown fter winter whet over wide re of southest Knss. Becuse this crop is vulnerble to wether-relted stress, such s drought nd erly frosts, it is importnt tht the vrieties hve not only high yield potentil under these conditions but lso the plnt structure to llow them to set pods high enough to llow hrvest. They lso should mture before thret of frost. Experimentl Procedures Twenty soyben vrieties were evluted in double-crop vriety tril following winter whet hrvest t Columbus on Prsons silt lom soil. Whet ws hrvested on June 17, The whet stubble ws burned, nd the soil fieldcultivted twice prior to plnting. Squdron ws pplied t 3.0 pt/ before the field cultivtions. Soybens then were plnted on June 23, 1994 t 10 seed per foot of row. The soybens were hrvested on October 19, 1994, with the exception of KS5292 which ws hrvested on October 25, The ltter dte ws for the MG V soyben, which mtured only fter frost in lte October. Results nd Discussion Yields rnged from 17 bu/ to 29.5 bu/. Severl vrieties yielded 25 bu/ or more. Creful considertion should be given to mturity nd the height to the first pod. The height to the first pod rnged from 3.5 in to 7.8 in. Most vrieties mtured before October

82 Tble 1. Yield of Double-Crop Vriety Tril for Soybens t Prsons, Knss, 1992 Yield 1994 Chrcteristics Brnd Vriety yr 3 yr Ht Ht to Mt Mt Avg Avg 1st Pod 3 yr bu/ in Oct Oct Golden Hrvest X Golden Hrvest Jcques Jcques Jcques Midlnd Midlnd N K S N K S Ohlde Ohlde Ohlde Pioneer Pioneer Stine Public Mnokin Public Hutcheson Public Flyer Public Avery Public KS (L.S.D. 0.05)

83 VARIETY RESISTANCE AND ROTATIONS FOR SOYBEAN CYST NEMATODE Jmes H. Long nd Timothy Todd 1 Summry The keys to reducing the effect of soyben cyst nemtode include the use of resistnt soyben vrieties nd rottion of crops to minimize its impct. Results from the cyst nemtode mngement studies t the Mrtin Frms Reserch Are in Columbus indicte tht the effect of using resistnt vrieties is greter thn previously thought. Rottion lso reduces the impct of the cyst nemtode. However, results from 4 yers show tht holding field out of susceptible soyben vrieties for 2 or even 3 yers my not be sufficient to overcome the problem. Introduction The soyben cyst nemtode (SCN) is serious problem in the estern U.S. It is persistent in the soil nd will continully rob soyben yield if good mngement prctices re not used ech yer. Mny cropping strtegies, including resistnt vrieties, hve been used to overcome this pest, yet it hs now spred to Knss. Ech region of the U.S. hs hd to develop loclly dpted soyben vrieties nd cropping rottions suited for tht re's griculturl soils nd climte. Southest Knss is region with shllow cly-pn soils tht re drought prone nd climte tht permits growth of long mturity crops such s MG (mturity group) V soybens. Becuse of the need to develop cropping strtegies nd evlute vrietl resistnce under southest Knss conditions, study ws strted in 1991 t the Mrtin Frms Cyst Nemtode Reserch Are in Columbus, Knss. Experimentl Procedures Six cropping systems rnging from 0 to 3 yers out of susceptible soybens nd with no soybens were strted in The systems include: 1. Continuous susceptible soybens. (no crop rottion) 2. Grin sorghum followed by susceptible soybens (1 yer out). 3. Grin sorghum followed by smll grin tht is followed by susceptible soybens (2 yers out). 4. Grin sorghum followed by resistnt soybens followed by grin sorghum then susceptible soybens (3 yers out). 5. Grin sorghum followed by smll grin tht is double-cropped to resistnt soybens followed by grin sorghum then smll grin doublecropped to susceptible soybens (3 yers out). 6. Grin sorghum followed by smll grin (no rottion to soybens). The susceptible soyben vriety ws 'By' nd the resistnt vriety ws 'Pioneer 9531', both erly to mid MG V soybens. Two sister studies with the sme rottions were run. One ws on hevily infested soils t the Mrtin Frms Cyst Nemtode Reserch Are, nd the second ws t the Southest Agriculturl Reserch Center - 1 Deprtment of Plnt Pthology, KSU. 79

84 Columbus Field, n re tht hs no detectble levels of the cyst nemtode. Results nd Discussion After 4 yers, differences could be seen in 1994 (Tble 1). The continuous susceptible By soybens t Mrtin Frms in 1994 yielded only two-thirds s much s the resistnt vriety, Pioneer 9531, tht is being grown in rottion. The continuous By vriety lso ended 1994 with 5 to 10 times more eggs/100 cm 3 thn found for Pioneer 9531 in rottion (Figure 1). After 4 yers, some rottions hve been held out of soybens for 3 yers. Grin yield (Tble 1) nd cyst nemtode differences mong rottions, seen in 1992 when soybens were grown fter nonsusceptible crop, were not evident in 1993 or This is probbly due to severl fctors, one of which is high rinfll tht enbled continuous susceptible soybens to grow reltively well. Thus, grin yield of susceptible soybens is very dependent on rinfll during the growing seson. In ddition, yields of susceptible soybens fter 3 yers out of soybens still did not equl resistnt soyben yields. This my be due to egg nd cyst levels developing rpidly during the growing seson on susceptible soybens, even when crop rottion gve reltively low erly-seson levels of the pest. Indictions re tht holding fields out of susceptible soybens for 3 yers my still not be enough to completely overcome the cyst nemtode nd llow the plnting of susceptible soybens. Results indicte tht crop rottion cn hve n impct on grin yield nd cyst numbers, depending on the yer. However, even fter 3 yers out of soybens, susceptible soybens will probbly be ffected severely in fields tht were initilly infested hevily with the soyben cyst nemtode. Selection of resistnt vriety hs the most consistent nd lrgest effect on grin yield. Tble 1. Effect of Crop Rottion on Soyben Grin Yield in Cyst Nemtode-Infested Soil. Rottion Yer By/By By 1 yr out By 2 yr out By 3 yr out Pioneer LSD ( 0.05 ) Rottion Figure 1. Effect of Crop Rottion on Soyben Cyst Nemtode Egg Numbers in Cyst Nemtode Infected Soils in

85 THE EFFECT OF CROP ROTATION AND VARIETY SELECTION ON CHARCOAL ROT AND SOYBEAN GRAIN YIELD Jmes H. Long, Timothy Tod 1 2, Dniel Sweeney, nd George Grnde Summry Experimentl Procedures Rotting from grin sorghum to soyben benefits both crops; however, the positive effects on the soyben crop re not well understood. Levels of the plnt disese, chrcol rot (Mcrophomin phseolin), were followed on soybens grown continuously nd in rottion with grin sorghum. Soyben grin yield incresed 12 % when group IV mturity soyben, Delsoy 4210, ws grown in rottion with grin sorghum. In ddition Delsoy 4210 yielded less thn fullseson group V mturity soyben, KS 5292, in Introduction Chrcol rot, plnt disese widespred in Knss, cn reduce the yield of soyben nd other crops. It rpidly infests the plnt during erly reproductive growth nd dversely ffects the plnt's root system nd lower stem. No genetic resistnce is known, lthough longer mturity vrieties my escpe the most devstting effects of the disese by setting pods lter in the summer when rinfll is more likely nd tempertures re cooler. Crop rottion is known to increse the yield of soybens, lthough the resons re uncertin. In n effort to better define the effect of crop rottion on soyben, field study ws begun in Severl cropping systems were estblished in 1988 t the Columbus unit of the Southest Agriculturl Reserch Center to help determine the effect of crop rottion on soyben. This report includes two of the systems: 1. Continuous soybens. 2. Soybens for 1 yer then grin sorghum. The erly MG (mturity group) IV vriety Delsoy 4210 nd the full seson MG V vriety, KS5292, hve been grown since 1993 s prt of study looking t crop rottion, soyben vrieties, nd plnt popultions. Dt were recorded from 1993 nd 1994 nd included grin yield, yield components, nd chrcol rot from the roots of the soyben plnts. The soil ws Prsons silt Lom (Mollic Albqulf). Rinfll verges 41 inches/yr t the site. Dt on soyben grin yield from two mturity groups (IV nd V) nd the crop rottions re reported here. Results nd Discussion The effects of chrcol rot on soybens could be seen clerly in 1994, especilly in the mturity group IV vriety Delsoy The vriety KS5292 outyielded Delsoy 4210 by 34 % in 1994 (Tble 1.). Rottion lso hd gret effect in both yers, with continuous Delsoy 4210 yielding 12 less thn Delsoy 4210 grown in rottion with 1993 to compre grin yield nd plnt disese grin sorghum. Crop rottion did not hve s levels of continuously grown soyben with gret n effect on the full seson KS soyben following grin sorghum. 1 Deprtment of Plnt Pthology, KSU. 2 Formerly t Southest Knss Experiment Sttion. 81

86 Tble 1. Effect of Vriety on Soyben Grin Yield During 1993 nd 1994 Yer bu/ Delsoy KS L.S.D.(.05) Tble 2. Effect of Crop Rottion on Soyben Grin Yield Rottion Soy-Soy Soy/Sorghum bu/ Delsoy KS L.S.D.(.10)

87 ANNUAL WEATHER SUMMARY FOR PARSONS Mry Knpp DATA Jn Feb Mr Apr My Jun Jul Aug Sep Oct Nov Dec Annul Avg. Mx Avg. Min Avg. Men Precip Snow * Het DD * Cool DD Rin Dys Min < Min # Mx $ NORMAL ( Averge) Jn Feb Mr Apr My Jun Jul Aug Sep Oct Nov Dec Annul Avg. Mx Avg. Min Avg. Men Precip Snow * Het DD * Cool DD DEPARTURE FROM NORMAL Jn Feb Mr Apr My Jun Jul Aug Sep Oct Nov Dec Annul Avg. Mx Avg. Min Avg. Men Precip Snow * Het DD * Cool DD * Dily vlues were computed from men tempertures. Ech degree tht dy's men temperture is below (or bove) 65E F is counted s one heting (or cooling) degree dy. 83

88 Temperture (OF) Precipittion (Inches) Temperture (OF) Precipittion (Inches)

89 ACKNOWLEDGEMENTS Listed below re individuls, orgniztions, nd firms tht hve contributed to this yer's reserch progrms through finncil support, product dontions, or services. Agrimeric, Inc., Northbrook, IL AgriPro Biosciences, Inc., Shwnee Mission, KS AGSECO, Girrd, KS Americn Cynmid Co., Wyne, NJ Brtlett Coop Assocition BASF Wyndotte Corp., Prsippny, NJ Bufflo Frm Equipment Co., Columbus, NE Cl-West Seeds, Woodlnd, CA CIBA Corp., Greensboro, NC DeLnge Seed Co., Girrd, KS Dow Elnco, Indinpolis, IN DuPont Agrichemicl Co., Wilmington, DE Frmlnd Industries, Knss City, MO FMC Corp., Phildelphi, PA Greenbush Seed & Supply, Inc., Hutchinson, KS Joe Hrris, Erie, KS Hrvest Brnds, Inc., Pittsburg, KS Jmes Hefley, Bxter Springs, KS Johnson Seed Co., Mound Vlley, KS Hoffmnn-LRoche, Nutley, NJ HybriTech Seed Intl., Inc., Wichit, KS J.D. Cttle Co., Hvn, KS Knss Soyben Commission, Topek, KS Kent Feeds, Musctine, IA Kerley Enterprises, Inc., Phoenix, AZ Mllinckrodt Veterinry, Terre Hute, IN Mrkley Seed Frms, Dennis, KS Mrtin Frms, Columbus, KS Merck & Co, Inc., Rhwy, NJ Micro-Lite Inc., Chnute, KS Miles Ag. Division, Knss City, MO Monsnto Agriculturl Products, St. Louis, MO Northrup King Co., Victori, TX Ohlde Seed Co., Plmer, KS Prsons Livestock Mrket, Prsons, KS Purin Mills, St. Louis, MO Pfizer, Inc., Lee's Summit, MO Pioneer Hi-Bred Interntionl, Johnston, IA Poli-Tron, Inc., Pittsburg, KS Resource Recovery, Inc., Coffeyville, KS Richrd Porter, Reding, KS R & F Frm Supply, Erie, KS Sndoz Agro. Inc., Des Plines, IL Dee Shffer, Columbus, KS SmithKline Beechm, West Chester, PA Syntex Agribusiness, Inc., Des Moines, IA Terr Interntionl, Inc., Chmpign, IL The Upjohn Co., Klzmoo, MI U.S. Borx & Chemicl Corp., Rosemont, IL Wilkinson Frms, Pittsburg, KS Zenec Ag Products, Wilmington, DE NOTE Trde nmes re used to identify products. No endorsement is intended, nor is ny criticism implied of similr products not mentioned. Contribution No S from the Knss Agriculturl Experiment Sttion. 85

90 RESEARCH CENTER PERSONNEL Lyle Loms Reserch Center Hed Mildred Beck... Office Assistnt II Tommie Phillippi... Office Assistnt II Lrry Buffington... Custodil Worker TLn Erikson... Lbortory Technicin III Mrl Sexton... Accounting Specilist Kenneth Coffey Animl Scientist Fredrick Blck... Animl Science Technicin I Lrry Ellis... Animl Science Technicin I Terry Green... Animl Science Technicin I Ronld McNickle... Animl Science Technicin II Robert Middleton... Animl Science Technicin II Jmes Long Crop Vriety Development Agronomist Joyce Erikson... Plnt Science Technicin I Chrles Middleton... Plnt Science Technicin II Kenneth Kelley Crops nd Soils Agronomist Michel Den... Plnt Science Technicin II Bobbie Hite... Plnt Science Technicin II Bobby Myers... Plnt Science Technicin II Joseph Moyer Forge Agronomist Mike Crmer... Kenneth McNickle... Plnt Science Technicin II Plnt Science Technicin I Dniel Sweeney Soil nd Wter Mngement Agronomist Phillip Mrkley... Dvid Kerley... Plnt Science Technicin II Plnt Science Technicin I 86

91 Agriculturl Experiment Sttion, Knss Stte University, Mnhttn