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1 2015, TextRod Puliction ISSN: Journl of Applied Environmentl nd Biologicl Sciences The Effects of Whet Plnt Residues Mngement nd Conservtion nd Conventionl Tillge Systems on Sugr Beet Yield Components nd Nutrients Amounts Slmn Slehin 1, Hossein Njfi 2, Seyyed Mohmmd Jvd Mirhdi 1, Ghorn Nourmohmmdi 1 1 Islmic Azd University, Science nd Reserch Brnch of Tehrn, Deprtment of Agriculture, Tehrn, Irn 2 Fculty memer of the Weed Reserch, Institute of Country Plnt Protection Reserch ABSTRACT Received: Novemer 21, 2014 Accepted: Jnury 5, 2015 In order to investigte the effects of tillge kinds nd whet residues nd their interctions effect on qulittive nd quntittive yield of sugr eet, n experiment s split plot form in rndomized complete lock design in the frming yer t the ws conducted. The min fctor includes tillge in two levels of conventionl nd conservtion nd whet su fctor residues t four levels includes zero (control), 1, 3 nd 5 tons per hectre. According to the vrince nlysis results of tillge t one percent prole on the lef dry nd soil phosphorus nd t the five percent prole on the lef fresh, roots dry hve significnt effect, ut on the root fresh, potssium nd nitrogen hve not significnt effect. Also whet residues t one percent prole on the soil potssium nd the interction effect of tillge with whet residues hve significnt effect on the soil potssium nd phosphorus t one percent prole. The otined results of men comprison showed tht the conventionl tillge cuses more lef fresh, lef dry nd root dry nd phosphorus in compring with conservtion tillge. Also the using of whet residues reduces soil potssium. KEYWORDS: nitrogen, phosphorus, potssium, tillge, whet residues. INTRODUCTION: Sugr production in mny countries is one on the essentil spects of its griculturl economics nd mong this sitution; sugr eet plnt plys n importnt role nd exclusively s source of sucrose is cultivted (koocheki, 1996). Reserchers re trying to develop sustinle growth of sugr eet production nd to minimize ny thret tht depends on the environment (Drycott, 2006). According to spects of soil qulity nd crop production tht hs incresed in recent yers, hs led to new interest in plnt residues, green mnures nd other orgnic fertilizers s source of orgnic fertilizer for the soil orgnic mtter nd plnt nutrient elements (Kumr, 1998). Plnt residues, the sic importnt resources, generlly re prts of plnts tht remin in the field fter hrvesting crops (Singh et l., 2003). Plnt residues cn replce with the nutrients in the soil, mintin the power of the griculture production, increse orgnic mtter, wter mintennce, stimulte microil ctivities, soil ggregtion nd reduce fluctutions in soil temperture, nd improve the plowing power nd reduce evportion of the soil. Plnt residues cn improve the wether qulity, reduce the runoff nd modify the effects of ir pollution. Also the plnt residues cn lnce in the glol climte y tking of orgnic cron nd reducing withdrwl of cron dioxide nd other greenhouse gses (Blnco-Cnqui nd Ll, 2009). Most frmers in the mngement of the plnt residues hve this concern tht hs the lest negtive effects on function nd cultivtion nd other plnts process. According to the this reson in long times wys such s the plnt residues urning, leving crop residue on the soil surfce, residues ccumultion of frm surfce nd residues plowing in the soil hs een discussed. Unfortuntely, due to lck of knowledge or lck of the life necessities, except limited use of these sustnces, frmers nd lnd owners nd rnchers ehviors with plnt residues re not rtionl nd principle. Sometimes to ese works, the otined nture work which should plce in the production cycle nd soil development nd networks nd food chins nd levels of crop ecosystem, is wrongly plowing nd is ffected y overgrzing or urning. Despite the incresing of soil nutrients tht ffected y plnt residue urning, most done studies show the dverse effects of this method is sed on the chrcteristics such s orgnic mtter nd soil permeility tht in the long times would endnger the production stility in the crop ecosystems (Due Preez et l., 2001). The plnt residue urning cuses the 80 percent nitrogen, 25 percent phosphorus, 21% potssium nd 40% to 60% sulfur losses nd destroy the soil microorgnisms (Gngwr et l., 2006). The plnt residues decying in the residue keeping tretment reduces the soil ulk density (Izurrld et l., Corresponding Author: Slmn Slehin, Islmic Azd University, Science nd Reserch Brnch of Tehrn, Deprtment of Agriculture, Tehrn, Irn. slmn.slehin@gmil.com 221

2 Slehin et l., ). But reserchers (Hynes nd Bers, 1996) stted tht the using of conservtion tillge in the frms increses the orgnic mtter nd therefore cuses the soil fertilities. Burning or removing plnt residues cn e fcilitted tillge opertion ut strw urning is dmged to the eneficil microorgnisms nd cuses soil erosion s well. In contrst, plnt residues remining on the soil surfce, reduces the soil erosion nd physicl, chemicl nd iologicl chrcteristics of the soil improves (Logsdon nd Krlen, 2004). In response to the incresing costs of fossil fuels, mssive soil erosion, intensive using of chemicl fertilizers nd pesticides nd environmentl concerns ssocited with wter pollution nd the pulic costs of doing usiness, tht the need of the new griculturl technologies is e felt. Studies show tht ech yer lrge re of crops lnds in the world due to soil compction nd erosion destroy. Therefore the using of pproprite strtegies to reduce nutrient losses nd soil erosion is essentil. Conservtion tillge system includes low tillge nd no-tillge tht is the one of the useful methods to prevent this prolem (Limousin nd Tessier, 2007). The otined results of n experiment in the Southern Sttes, Ontrio, Cnd, showed tht no-tillge system in compring with the conventionl tillge system reduces the 61 percent of the crop costs during yer (Weersink et l., 1992). Reserchers sy tht in the notillge system in compring with conventionl tillge systems, more moisture stored in the soil. This moisture incresing in the conservtion tillge is minly the result of etter penetrtion of wter in the soil, evportion nd runoff decresing (Opoku nd Vun, 1997). The reserchers stted tht in the no-tillge system in compring with the conventionl tillge of soil crust, specific ulk density nd soil compction decreses (Hermown nd Cmeron, 1993). Also the conservtion tillge systems in compring with conventionl tillge increse the nutrients in the soil (Alvrez et l., 1995). Reserch results show tht the tillge systems lso effect on the plnts yield. In the 5 yer experiment, cotton yield in the first two yers of the no-tillge system in compring with the conventionl tillge nd disc nd chisel were lower, ut three yers lter, no-tillge system increses the yield nd lso more precocious of production in mount of 6 to 10 dys in compring with the conventionl tillge systems (Triplett et l., 1996). Reserchers the implementtion of minimum tillge frming methods s eneficil effect fctor on the soil chrcteristics such s structure nd incresing of the orgnic mtter nd production hve een reported (Isml et l., 1994). In generl oserved tht crop cultivtion cn reduces soil orgnic mtter especilly if it is comined with conventionl tillge nd moldord plow (Lmpurlns et l., 2001). Conservtion tillge cn increse soil porosity nd soil wekness nd llow moving nd pproprite exchnge of ir in the soil nd increses root growth (Lpen et l., 2004). Due to the plnt residues s n input within the field in the nutrients supplying of plnt need such s potssium nd the importnce of tillge s n pproprite strtegy to reduce soil erosion nd nutrient losses of this study to determine the effect of plnt residues nd conservtion tillge difference with conventionl tillge nd provide the required elements on sugr eet plnts were conducted. MATERIALS AND METHODS This experiment in the frming yer t in the reserch field t the phytopthology Reserch Institute Locted on the Meshkindsht rod of Krj ws conducted. Averge nnul rinfll of tht re 250 mm nd the verge nnul temperture, 16.2 C ws oserved. This experiment lso s split plot form in rndomized complete lock design with three replictions ws conducted. Investigted tretments in this reserch were included the tillge opertion t two levels of conservtion nd conventionl tillge s the min fctor nd the use of different mounts of whet plnt residues t four levels of zero (control), 1, 3 nd 5 tons per hectre s suplot on the sugr. To determine the physicl, chemicl chrcteristics, nd to mesure the sitution nd the mount of nutrients elements of it, the soil smpling ws sent to the lortory nd mentioned chrcteristics were mesured. The soil specifictions in Tle 1 re presented. Tle 1. Chrcteristics of the exmined soil Depth Tissue EC (ds/m) ph O.C (%) N (%) P (ppm) K (ppm) (cm) 0-30 Lom In order to pply the experimentl tretments, the experiment mp nd privcy experimentl plots were identified in utumn Whet plnt residues ccording to the desired vlues in the experimentl plots were distriuted mnully. In Decemer 2013, relted plots to the conventionl tillge y moldord plow ploughed nd then cretion of plots ws done. Plots in length of 10 meters nd in width of 6 meters were oserved nd hs 11 plnting rows nd etween ech plot ws not plnted row. The distnce etween the locks ws 3 m nd plnt distnce on ech row of ech other cm with density 10 plnts per m2. In this study, the modified sugr eet 222

3 seeds clled Tort figure ws used, which ws prepred y the Institute of plnt nd seed in Krj. Cultivtion of sugr eet seed t the first week of My of 2013 ws conducted. After full emergence, 4-lef stge of sugr eet thinning opertion nd gp filling to chieve the desired density ws conducted nd control plots of ure fertilizer ws pplied in three stges. Wtering opertion ccording to plnt need ws done. The finl of hrvesting time to remove mrginl effect of one meter from the eginning nd end of ech plot, were eliminted nd the rest of the hrvest ws performed. The leves nd roots were seprted nd weighed seprtely nd were plced in pper gs nd in the oven t 75 C for 48 hours ws dried. After tht the smples were removed from the oven nd weighed with sensitive scle. The mesured chrcteristics in the soil ws included the food elements nitrogen (kejeldhl method), phosphorus (olsen method), nd potssium (flme photometer method) (Asdokht nd Chichi, 2001). In order to dt nlysis from the SPSS sttisticl softwre nd for the dt men comprison from Duncn's multiple rnge test t the five percent prole level were used. RESULTS Lef fresh : Vrince nlysis results (Tle 2) showed tht tillge type hs significnt effect t five percent prole on the lef fresh ut hs not significnt effect on the whet residues nd the interction effect of tillge with whet residues. The men comprison results re influenced y tillge showed tht lef fresh in the conventionl tillge in mount of ( kg per hectre) is more thn conservtion tillge in mount of ( kg per hectre) nd cused significnt increse in lef fresh tht represents n increse in mount of percent of lef fresh in the conventionl tillge in compring with conservtion tillge (Tle 3). According to the men comprison results of the interction effect of tillge types with different levels of whet residues, the most lef fresh in mount of kg per hectre in the tretment without using of whet residues in the conservtion tillge nd the lowest lef fresh in mount of kg per hectre in the tretment in mount of 1 ton per hectre of whet residues in the conservtion tillge were otined (Tle 5). Lef dry : Vrince nlysis results (Tle 2) showed tht tillge type hs significnt effect t one percent prole on the lef dry ut hs not significnt effect on the whet residues nd the interction effect of tillge with whet residues. The men comprison results of lef dry re influenced y tillge fctor showed tht lef dry in the conventionl tillge in mount of ( kg per hectre) nd conservtion tillge in mount of ( kg per hectre) were otined, on the other words lef dry in the conventionl tillge in mount of percent ws more thn conservtion tillge (Tle 3). The men comprison results of the lef dry re influenced y tillge type nd different levels of whet residues showed tht the most lef dry in mount of (786.8 kg per hectre) in the tretment without using of whet residues in the conservtion tillge nd the lowest lef dry in different levels of whet residues in the conservtion tillge ws otined (tle 5). Root fresh : According to the vrince nlysis results etween different types of tillge, whet residues nd the interction effect of tillge with whet residues were not otined significnt difference on the root fresh in the conducted experiments (Tle 2). Root dry : Vrince nlysis results showed tht pplied tillge on the root dry t the five percent prole hs significnt effect ut whet residues nd the interction effect of tillge with whet residues hve not significnt effect on the root dry (Tle 2). According to the otined results from tillge men comprison ws found tht the most root dry in mount of kg per hectre is relted to the conventionl tillge nd the lowest root dry in mount of kg per hectre is relted to the conservtion tillge which represents the difference in mount of percent conventionl nd conservtion tillge in the root dry (Tle 3). Also the men comprison results of the interction effect of tillge with whet residues showed tht the most root dry in mount of kg per hectre is relted to the lck of whet residues y using in the conventionl tillge nd the lowest root dry in mount of kg per hectre is relted to the 3 ton per hectre of whet residues using in the conservtion tillge (Tle 5). potssium: The otined informtion of vrince nlysis results showed tht whet residues nd the interction effect of tillge with whet residues t one percent prole hve significnt effect on the potssium ut there ws no significnt effect in the tillge tretment (Tle 2). The men comprison results of influenced y whet residues showed tht the mount of potssium y incresing of whet residues ws decresed, so tht the most mount of potssium ( ppm) in the control tretment nd the lowest mount of potssium ( ppm) in the tretment of 1 ton per hectre of whet residues ws oserved (Tle 4). According to the potssium men comprison tht influenced y tillge kind nd different level of whet residues, the most potssium in mount of 254 nd ppm is relted to the 5 ton per hectre of whet residues in the conservtion tillge nd the sence of whet residues in the conventionl tillge ws otined (Tle 5). 223

4 Slehin et l.,2015 phosphorus: The otined informtion of vrince nlysis results showed tht whet residues nd the interction effect of tillge with whet residues t one percent prole hve significnt effect on the phosphorus ut there ws no significnt effect in the tillge tretment (Tle 2). The men comprison results of phosphorus tht influenced y whet residues showed tht the phosphorus in mounts of 6.62 ppm nd in the conservtion tillge 6.26 ppm were oserved tht ws indicted to the incresing of percent in the conventionl tillge (Tle 3). According to the phosphorus men comprison tht influenced y tillge kind nd different level of whet residues, the most phosphorus in mount of (7.61 ppm) in lck of whet residues tretment in conventionl tillge ws otined (Tle 5). nitrogen: The otined informtion of vrince nlysis results showed tht the min effects of tillge nd whet residues s well s the interction effect of tillge with the min effects of tillge nd whet residues s well s the interction of tillge with whet residues hd no significnt effect on the nitrogen (Tle 2). Tle2. Vrince nlyze results of tillge nd whet residues effects on the sugr eet yield nd soil food elements S.O.V df Lef fresh Lef dry Root fresh Root dry nitrogen potssium phosphorus Block ns ns ns ns ns 0.13 ns ns Tillge () * ** ns * 54 ns 2.59 ** ns Error Whet residues () ns ns ns ns ** 0.25 ns ns * ns ns ns ns ** 2.98 ** ns Error CV% **, * nd ns re significntly t 1%, 5% nd not significnt, respectively Tle3. The men comprison of tillge effect on the sugr eet yield nd soil food elements Tillge Lef fresh Lef dry Root fresh Root dry potssium phosphorus nitrogen (%) (kg.h -1 ) (kg.h -1 ) (kg.h -1 ) (kg.h -1 ) (ppm) (ppm) Conservtion Conventionl Ech vlue is the men of three replictes. Vlues followed y different letters in ech column re significntly different t P 5 Tle4. The men comprison of whet residues effect on the sugr eet yield nd soil food elements Lef fresh Lef dry Root fresh Root dry potssium phosphorus (kg.h -1 ) (kg.h -1 ) (kg.h -1 ) (kg.h -1 ) (ppm) (ppm) Whet residues (ton.h -1 ) nitrogen (%) c Ech vlue is the men of three replictes. Vlues followed y different letters in ech column re significntly different t P 5 Tle 5. The men comprison of tillge nd whet residues effects on the sugr eet yield nd soil food elements Tillge Whet residues (ton.h -1 ) Lef fresh (kg.h -1 ) Lef dry (kg.h -1 ) Root fresh (kg.h -1 ) Root dry (kg.h -1 ) potssium (ppm) phosphorus (ppm) nitrogen (%) Conservtion c Conservtion c 5.9 c Conservtion Conservtion Conventionl Conventionl c Conventionl Conventionl c 5.87 c Ech vlue is the men of three replictes. Vlues followed y different letters in ech column re significntly different t P 5 224

5 DISCUSSION In one study suggested tht the min reson to reducing the soil content elements is the ddition of lrge mount of plnt whet residue. orgnic mtter is the min energy source for soil microorgnisms. microorgnisms to continue ctivity in ddition to cron, needs to the nitrogen nd nutrients tht provides these food elements from the soil nd y incresing soil orgnic cron nd intensified microorgnisms ctivity, their needs to the food elements ws incresed nd lrge mount of soil food elements re sored y them. Also the reson of lck of whet residue effect on phosphorus nd nitrogen into the wooden nd declred long time to rote residue (Due Preez et l., 2001). In the no till system nd the tillge frming system, the wter infiltrtion due to the pores existence which is formed y soil cretures cn e incresed. In the no till system nd the tillge cropping system, deep gps re formed in the soil tht these gps lso cn help to increse the soil moisture storge (Meek et l., 1990). Reserchers (Wright nd Hons, 2005) lso reported tht the using of no-tillge methods cused significnt increse in the ggregtes, orgnic cron nd nitrogen mounts in the soil. Reserchers (Ismil et l., 1994) implementtion of minimum tillge frming method considered s fctor tht hs eneficil effects on soil chrcteristics such s improving the structure nd incresing the orgnic mtter nd production hve reported. The incresing of volumetric soil moisture holding cpcity in the no tillge system nd the minimum tillge crop y (Cox et l., 1990) hs een reported. According to (Ossile et l., 1992) underly compction of the soil nd to ecome thicker nd shorter of roots in the soil compression re reduces grin nd strw yield in no tillge system. Aout the incresing of qulittive nd quntittive yield, there re some reports in the tillge systems in compring with the conventionl tillge. Reserchers (wright et l., 2007) stted tht the yield incresing in the low tillge systems in compring with the conventionl tillge hs more ccessile to phosphorus nd nitrte t the soil surfce. Zilske et l., 2002) reported tht in the low tillge system, physicl, chemicl nd iologicl chrcteristics in the soil surfce nd in the root ctivity region is improved nd due to chnge in minerliztion nd more stility of the nutrient in the soil y incresing the ctivity of the microil popultion, the supply of nutrients to plnts ws increse (wright et l., 2005). No tillge system reduces the erosion nd runoff nd increse wter infiltrtion in the soil nd supply more moisture for plnts increses the orgnic mtter in the soil surfce nd in ddition, cuses the vilility of nutrients for plnts (Wddell nd Weil, 2006; Fng et l., 2003). The study (2010) Suddick et l., Show tht the use of rice residues with different tillge tretments on whet yield components hs een effective which hs not correspond with the otined results in the experiment. Tillge opertion effects on iologicl ctivity, ccess to food sources, receiving, storge nd trnsport of wter in the soil, erosion resistnce, hydrulic conductivity, ventiltion, soil het nd lso y relesing the nutrients effect on the plnt growth nd production nd mechnicl resistnce of the soil (Lopez-Fndo & Almendros, 1995; Mlicki et l., 1997; Miknov et l., 2009). According to eer et l., (1994) reserches, the conventionl tillge cuse the more nd fster of plnt residues decomposition nd the ville cron nd nitrogen in the orgnic mtter tht turned to the minerl very fst nd therefore the orgnic mtter is lost fster. In study, the effect of different methods of tillge on corn growth ws evluted. The results showed tht the mximum mounts of growth nd corn plnt emergence in conventionl tillge (moldord plowing) nd the trnsition or displcement methods in mount of 30 cm from the seed estlishment plce is more thn the without plowing (no tillge). They the reson of this issue, the high tempertures in the plowed re (20 cm depth) nd seed estlishment plce (5 cm depth) ws noted (Azooz et l., 1995). REFERENCES 1. Asdokht, H., Chichi,M.R Allelopthic potentil of chickpe (desi type) on germintion nd erly growth of sorghum, soyen nd sunflower. Journl of Agriculturl Sciences of Irn. Vol Alvrez, R., Sntntogli, O.J., Grcio,R Effect of temperture on soil microil iomss nd its metoolic quotient insitu under different tillge systems. Biol. Fertil. s. 19: Azooz, R.H., Lowery,B., Dniel, T.C Tillge nd residue mngement influence on corn growth. nd Till.Res.33: Ber, M.H., Hendrix, P.F.,nd Colemn, D.C Wter stle ggregtes nd orgnic mtter frction in conventionl nd no-tillge. Sci. Soc. Am. J. 58: Blnco-Cnqui, H., Ll, R Crop residue removl impcts on soil productivity nd environmentl qulity. Criticl Reviews in Plnt Sciences. 28:

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