in 1976 (Lawrence 1976), but information This paper reports on studies to determine

Transcription

1 SD YLD OF ALTA WLD RYGRASS AS NFLT]N BY ROW SPACNG AND FRTLZR T. LAWRNC Research Statin, Research Branch, Agriculture Canada, Swift Current, Saskatchewan SgH 3X2. Received 8 May 1979, accepted 20 Sept Can. J. Plant Sci. Dwnladed frm by n 01/01/18 Fr persnal use nly. LawnrNcs, T Seed yield f Altai wild ryegrass as influenced by rw spacing and fertilizer. Can. J. Plant Sci. : A study was cnducted frm 1969 t 1977 t determine the effect f rw spacings and applicatins f N and P fertilizer n the prductivity f Altai wild ryegrass (lymus ansustus Trin.). The ptimum rw spacing fr highest seed prductin was 120 cm and the ptimum fertilizer treatment was 25 kg N/ha plus 25 kg P/ha annually. Dubling the rate f N r N plus P did nt significantly increase the seed yield ver that btained frm grass receiving the 25 kg N plus 25 kg P per hectare rate. Fertilizer treatments cntaining P tended t result in a mre stable year-t-year respnse than thse cntaining nly N. Altai wild ryegrass grwn in -cm rw spacings prduced higher dry matter yields fr the first 4 yr than that grwn in wider-spaced rws. Hwever, in the last 4 yr highest yields were btained frm grass seeded in rws spaced 150 cm apart. Grass receiving an annual applicatin f 50 kg N/ha plus 50 kg P/ha prduced significantly mre frage than that given,nly 25 kg N/ha, bth f which utyielded unfertilized grass. De l969dl9tt,naeffectu6une6tudepurd6terminerl'effetdedivers6cartements des lignes et fumures azt6es et phsphat6es sur la prductivit6 de l'6lyme de 'Altai (lymus angustus Trin.). L'6cartement ptimum permettant la plus frte prductin grainidre fut de 120 cm et la meilleure fumure fut de 25 kg de N/ha plus 25 kg de P/ha appliqu6s annuellement. Le fait de dubler la dse de N u de N plus P n'a pas significativement accru la prductivit6 par rapprt h celle btenue de la fumure susmentinn6e. Les traitements fertilisants ir base de P nt eu tendance h stabiliser davantage la prductivit6 d'ann6e en ann6e que ceux ne cmprtant que du N. L'6lyme de 'Altai cultiv6 h des 6cartements de cm a prduit de plus frts rendements grainiers au curs des 4 premibres ann6es que celui sem6 i 6cartements plus cnsid6rables. Mais au curs des 4 dernibres ann6es, la plus frte prductivit6 a 6t6 btenue avec des lignes 6cart6es de 150 cm. L'applicatin annuelle de 50 kg de N/ha plus 50 kg de P/ha a prduit significativement plus de furrage que la seule fumure de 25 kg de N/ha, mais les deux traitements nt permis de surpasser les rendements de l'6lyme nn fertilis6. Altai wild ryegrass (lymus angustus Tnn.) management practices is lacking. Laynenqe shws great ptential as a pasture grass fr studied the influence f aftermath remval Western Canada (Kilcher and Lawrence (1973a) and spring cutting (1973b) n the l979;lawrence 1974, l977;lawrence and seed yield f this grass and fund that the Heinrichs 197O, 1974; Lawrence and Ldge seed yield was enhanced by clipping the 1975). Hwever, lw seed prductin is a aftermath n seed fields. Similar results majr prblem. Prairieland, a smewhat were btained by using field aftermath fr higher seed-yielding cultivar, was licensed fall pasture (Lawrence and Ldge 1975). in 1976 (Lawrence 1976), but infrmatin This paper reprts n studies t determine n the respnse f this grass t varius theinfluencefrwspacingandfertilizern the seed and dry matter yield f Altai wild cn. J. Plrnt sd. fc 2llzB (J.n. 19S0) ryegrass. 249

2 250 CANADAN JOURNAL OF PLANT SCNC Can. J. Plant Sci. Dwnladed frm by n 01/01/18 Fr persnal use nly. MATRALS AND MTHODS Altai wild ryegrass was seeded in 1969 n dryland summer fallw in a six-replicate split-plt design. The main plts cnsisted f rw spacings f,,, 120, and 150 cm. ach main plt was subdivided int the fllwing treatments: (a) n fertilizer, (b) 25 kg N/ha, (c) 25 kg N/ha + 25kg P/ha, (d) 50 kg N/ha and (e) 50 kg N/ha + 50 kg P/ha. The N was supplied as and the P as The plts were 6.1 m lng. Thse in which the grass was seeded in -crn spacings cnsisted f six rws, whereas thse seeded in spacings f,, l2o and 150 cm cnsisted fthree rws. The rate f seeding fr the Altai wild ryegrass was cnstant, 100 seeds per meter, regardless f rw spacings. Fertilizer was applied each August after seed harvest. The sil was an Orthic Brwn Chernzem belnging t the Wd Muntain assciatin and the mean annual precipitatin during the test perid was 336 mm. RSULTS Bth rw spacing and fertilizer had significant effects n the seed yield f Altai wild ryegrass (Table ). Seed yield increased with increasing rw spacing up t the 120-cm spacing, but it was nt increased further by using a 150-cm rw spacing. The yield difference between narrw and wide rw spacing increased with increasing age f stand (Fig. l). Altai wild ryegrass given 25 kg N/ha did nt yield mre seed than unfertilized grass (Table l). Hwever, when 25 kg P/ha was t970 7t Yer Fig. l. Seed yield f Altai wild rydgrass as influenced by rw spacing. added with 25 kg N/ha a significant increase in seed yield was btained. Dubling the rate fn r N + P did nt significantly increase the seed yield ver that btained with the 25 kg N/ha + 25kg P/ha treatment. Althugh Table l. ffect f rw spacing and fertilizer n the seed yield f Altai wild ryegrass ct'.g 0ct ' s!, OL t50 l 50 Ttal seed yield (kg/ha, 8 yr) /\ /r ii l.i fir{ li \ it '. Spacing N-P fertilizer (kg/ha) (cm) O Mean 150 Mean D (P : 0.05) spacing 294. D (P : 0.05) fertilizer : l5l nteractin spacing x fertilizer : NS r'76 l t t r il19 r243 l3 t '78' t4t6 42r t7 t t224 t28'7

3 LAWRNC - SD YLD OF ALTA RYGRASS 25r Can. J. Plant Sci. Dwnladed frm by n 01/01/18 Fr persnal use nly. the 8-yr ttal yields d nt shw it, there was cnsiderable variatin in fertilizer respnse with increasing age f the stand (Fig. 2). Bth f the fertilizer ffeatments cntaining P tended t give a mre stable year-t-year respnse than thse cntaining nly N. This influence fp fertilizer n seed yield had nt been fund in earlier studies with Russian wild ryegrass (lymus junceus Fisch.) (Lawrence 1963). The ttal 8-yr dry matter yield indicates that rw spacing did nt have a significant influence n the dry matter yield (Table 2). Hwever, a graphic presentatin f the annual yields reveals that grass in wide rw spacings was less prductive than grass in g q, F -c (L -! + z : s.1, 3.9 (, (n. r r80 r70 r t40 r t t k9N+OkgP/h 25 k9 N + 25 kg P/h 50 k9 N+ 0k9 P/h 50 kg N+ 50 kg P/h r OkgN+OkgP/h Yer Fig..2. Seed yield f Altai wild ryegrass as influenced by N and P fertilizer. narrwly-spaced rws fr the first few years f the study, but much mre prductive in later years (Fig. 3). These tw effects average ut t indicate n difference when nly the ttal yield is cnsidered. Obviusly, fr lng-term stands wide rw spacings wuld be imprtant fr maximum dry matter yield. Fertilized grass prduced significantly mre dry matter than that which was nt fertilized (Table 2). Grass given an annual applicatin f 50 kg N/ha + 50 kg P/ha prduced significantly mre frage than that receiving nly 25 kg N/ha per year. Phsphrus fertilizer did nt appear t be as useful in terms f increased dry matter yield as it was in terms f increased seed yield (Fie. a). r40.! rs, tz ;il rrt too ss 3e ;s le & <20 t 6,0 cm ' O cm t2 cm - -- ' cm f a Yer Fig. 3. Diy matter yield f Altai wild ryegrass as influenced by rw spacing.

4 252 CANADAN JOURNAL OF PLANT SCNC Can. J. Plant Sci. Dwnladed frm by n 01/01/18 Fr persnal use nly. c F (L : Ct! + z r J s, ; (l t r40 r il r t 25k9N +OkgP/h 25kgN+25k9Plh 50kgN+OhgP/h 50tgN +50kgP/h O k9n+okg P/h f970 7t yer Fig. 4. Dry matter yield f Altai wild ryegrass as influenced by N and P fertilizer. Spacing (cm) q) Mean Analysis f sil samples taken frm each plt prir t the first fertrlizer applicatins shwed the sil was lw (Saskatchewan Sil Testing Labratry ) in bth N and bicarbnate-sluble P (Table 3). Similar samples taken after seed harvest n terminatin f the test 8 yr later shwed that N levels were still lw, indicating n build-up f nitrates in the sil (TabG 3). Where P fertilizer had been applied, the P cncentratin in the 0- t l5-cm sil layer was cnsiderably abve that at the start fthe study and abve thse plts where P fertilizer was nt applied. The cnclusin is that t maximize seed prductin f Altai wild ryegrass under dryland cnditins such as these ne shuld use rw spacings f 120 cm. Fr a clay lam sil with less than 3 ppm NOB-N and less than 8.5 ppm P in the tp 15 cm f sil, annual applicatins f25 kg N/ha and 25 kg P/ha are required. Fr sustained frage yields n these sils ver a lng perid f years, rw spacings f -120 cm and annual applicatins f kg N/ha are recmmended. KLCHR, M. R. and LAWRNC, T Spring and summer pastures fr suthwestern Saskatchewan. Can. J. Plant Sci. 59: LAWRNC, T Seed yield f Russian wild ryegrass grwn n an irrigated clay sil in Table 2. ffect f rw spacing and fertitizer n the dry matter yield f Altai wild ryegrass Ttal dry matter yield (kg/ha, 8 yr) N-P fertilizer (kg/ha) l l5 815 t5 317 l5 618 D (P 0.05) spacing NS. D (P 0.05) fertilizer nteractin spacing x fertilizer: NS. l r't 372 l l8 062 l l7 065 l r t r l9 450 t8 526 t l l r t8 177

5 LAWRNC_ SD YLD OF ALTA RYGRASS 253 Table 3. Analysis fsil samples cllectedin the fall prirt firstfertilizerapplicatin andatthe end fthe test(rw spacing effects were nt significant s values were averaged ver spacings) Can. J. Plant Sci. Dwnladed frm by n 01/01/18 Fr persnal use nly. Start r end f test Start Start nd Depth (cm) l Mean l Mean ' Mean r7 Mean ' Mean Mean 4.28 Fertilizer treatments N-P (kg/ha) D (P 0.05) s Mean Fert. Depth N-NOsppm O t l.9l 2.t N-NH3 ppm t O 't P ppm ' suthwestern Saskatchewan. J. Range Manage. 16:3ll-312. LAWRNC, T. 1973a. Seed yietd f Altai witd ryegrass as influenced by aftermath remval. Can. J. Plant Sic LAWRNC, T. 1973b. Cntrl f seed culm frmatin n Altai wild ryegrass by spring cutting. Can. J. Plant Sci. 53: LAWRNC, T The intrducrin, evaluatin and ptential f lymus angustrs Trin. as a frage crp in Western Canada. Prc. X nt. Grassland Cngr., Mscw, U.S.S.R. LAWRNC, T Prairieland, Altai wild ryegrass. Can. J. Plant Sci. 56: LAWRNC, T. lg'li. Altai wild ryegrass. Agric. Can. Publ O5 t s ^t8 1. r r.22 4.' NS.24 NS NS LAWRNC, T. and HNRCHS, D. H Pasture attributes f Altai wild ryegrass. Can. J. Plant Sci. 50: LAWRNC, T. and HNRCHS, D. H Altai wild ryegrass fr winter pasture. Can. J. Plant Sci. 54: LAWRNC, T. and LODG, R. W Grazing seed field aftermath f Russian wild ryegrass, Altai wild ryegrass and green needlegrass. Can. J. Plant Sci. 55: SASKATCHWAN SOL TSTNG LAB. 19' Nutrient guidelines fr Saskatchewan Sil Science Department, University f Saskatchewan. Saskatn. Sask.