Integrated Management of Sclerotium rolfsii (Sacc.) in Groundnut (Arachis hypogaea L.) under Pot Culture Conditions

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1 Pst Thnology 2011 Glol Sin Books Intgrt Mngmnt of Slrotium rolfsii (S.) in Grounnut (Arhis hypog L.) unr Pot Cultur Conitions Appnn Vikrm 1* Hillh Hmzhzrghni 2 1 Potto Dvlopmnt Cntr, Nw Brunswik Dprtmnt of Agriultur & Aquultur, Wiklow, Nw Brunswik, E7L 3S4 Cn 2 Dprtmnt of Plnt Prottion, Collg of Agriultur, Bjgh, Shirz Univrsity, Shirz, Irn Corrsponing uthor: * vikrmppnn@yhoo. ABSTRACT Collr rot of grounnut us y Slrotium rolsfii is iss of signifint onomi importn in grounnut-growing rs of th worl. In th prsnt tril n intgrt pproh ws follow in pot ultur onitions for ssssing mngmnt of S. rolfsii in grounnut using iffrnt ioontrol gnts, hmil trtmnts n orgni mnmnts. Th tril ws sign s rnomiz omplt lok ontining ight trtmnts t 45 n 90 ys ftr sowing h rplit thr tims. Th trtmnt omintions wr: 1) untrt ontrol; 2) inoult with Psuomons fluorsns FPD-10; 3) P. fluorsns FPD-15; 4) Trihorm hrzinum; 5) nm k; 6) Cptn; 7) P. fluorsns FPD-10 + T. hrzinum n ppli with nm k + Cptn n 8) P. fluorsns FPD-15 + T. hrzinum n ppli with nm k + Cptn. All trtmnts wr inoult with S. rolfsii n Bryrhizoium sp. NC-92 t th tim of sowing. All trtmnts tst ror signifintly lowr prntg of pos inft with S. rolfsii n rsult in highr po yil ompr to untrt ontrol. Th highst po yil ws ror in plnts riving P. fluorsns FPD-10, follow y omintion of iffrnt trtmnts with FPD-10 n omintion of iffrnt trtmnts with P. fluorsns FPD-15. Although iniviul pplitions of ithr T. hrzinum or nm k or ptn i not giv similr rsults s singl inoultions of ithr FPD-10 or FPD-15, it i signifintly ru th po inftion us y S. rolfsii n improv po yil. Sin most of th trtmnts tst in this tril ru po inftion n inrs po yil it is nssry tht ths trtmnts tst unr fil onitions for thy n xploit in ommril st up. Kywors: ollr rot, plnt growth promoting rhizotri, Psuomons fluorsns, Trihorm hrzinum INTRODUCTION Th inisrimint us of hmil pstiis n frtilizrs in morn griultur hs rsult in th vlopmnt of svrl srious prolms. Ths inlu pstii rsistn in psts, rsurgn of trgt n non-trgt psts, strution of nfiil orgnisms, n prsn of hmil rsius in foo, f n for. Th us of hmil frtilizrs hs lso n nssry u to ultivtion of high yiling vritis. This hs rsult in grtion of soil hlth (Cook 1991). Hn ltrntiv mthos r ing nvisg in n ofrinly pproh im t sustinl griultur. Biologil mthos offr n xllnt ltrnt strtgy for fftiv ontrol of vrious isss n ugmnttion of nutrint vilility in th rhizosphr. Comin us of iffrnt ioontrol gnts or intgrtion of ioontrol gnts with othr iss mngmnt options, with intifil iffrns in thir mhnisms of tion, hs improv iss prottion n th tivity sptrum of ioontrol gnts (Jtiynon n Kloppr 2002). Th omin us of ru oss of fungiis n ioontrol gnts offr n fftiv ontrol of soilorn isss whr hmil ontrol lon ws unfforl (Duffy 2000; Konoh t l. 2001). In som ss th omin pplition of fungii n fungii-tolrnt ioontrol gnts ru th svrity of stm rot, mping off n posthrvst rot in grounnut (Arhis hypog L.), tomto (Lyoprsion sulntum L) n pr (Pyrus ommunis L.), rsptivly (Konoh t l. 2001; Mnjul t l. 2004). Plnt growth-promoting rhizotri (PGPR) offr n xllnt omintion of trits usful oth in iss ontrol n inrs nutrint vilility. Th fluorsnt psuomons stn out mong PGPRs u to thir high lvl of gnti vriility n omptitivnss in th soil. Hn, ths hv n vot s fftiv n onomil ioinoulnts for us in intgrt nutrint n pst mngmnt systms. Stuis hv shown tht thy hv n us s s inoulnts to supprss plnt pthogns, promot plnt growth n inrs rop yils (Dfrits n Grmi 1990; Dy t l. 2004). Grounnut is n importnt oils rop (Brown 1999) ut th mximum proutivity hs not n rh u to lrg rution in yil owing to numr of isss (My n Dtr 1988; Gnsn n Skr 2004). Among iffrnt isss of grounnut, ollr rot us y Slrotium rolfsii is iss of onsirl onomi importn in grounnut proution. of th fungus is iffiult s it os not prou sxul spors n ovrwintrs s slroti, th primry inoul for th following sson, on plnt ris n in soil (Punj 1988). It is suggst tht th vill sours of host plnt rsistn n hmil ontrol n to strngthn for fftiv mngmnt of this iss in grounnut (Poil n Kishor 2002). On of th wys to ru th loss is to grow rsistnt vritis whih n onntrt fforts in plnt ring. Altrntivly, ths n ontroll y using ioontrol gnts (Aysingh 2009; H 2010; Ozgonn t l. 2010). Th ffiy of ontrol my improv y using n intgrt pproh involving iffrnt ioontrol gnts, hmil trtmnts n orgni mnmnts. In th prsnt stuy n ttmpt ws m to stuy th fft of Psuomons fluorsns FPD- 10 n FPD -15, Trihorm hrzinum, ptn n nm k on ontrol of Slrotium rolfsii in grounnut unr pot ultur onitions. Riv: 6 Mrh, Apt: 4 Dmr, Originl Rsrh Ppr

2 Pst Thnology 5 (1), Glol Sin Books MATERIALS AND METHODS An intgrt pproh ws follow for ssssing th mngmnt potntil of Slrotium rolfsii in grounnut y using Psuomons fluorsns FPD-10 n FPD-15, Trihorm hrzinum, ptn n nm k unr pot ultur onitions. Th tril ws sign s rnomiz omplt lok with ight trtmnts t 45 n 90 ys ftr sowing h rplit thr tims. Th trtmnt omintions wr: 1) untrt ontrol; 2) inoult with P. fluorsns FPD-10; 3) inoult with P. fluorsns FPD-15; 4) inoult with T. hrzinum; 5) ppli with nm k; 6) ppli with Cptn; 7) inoult with P. fluorsns FPD-10 + T. hrzinum n ppli with nm k + Cptn n 8) inoult with P. fluorsns FPD-15 + T. hrzinum n ppli with nm k + Cptn. All th trtmnts wr inoult with S. rolfsii n Bryrhizoium sp. NC-92 t th tim of sowing. Soil typ, ss n frtilizr Th soil us in th stuy ws mium lk ly ollt from 0-15 m pth of E-lok, plot numr 125 of Min Rsrh Sttion (MRS), UAS, Dhrw. Th ollt soil ws mix thoroughly, siv n fill in rthn pots of 30 m imtr n 30 m hight t th rt of 12 kg pot -1. Th rquir quntity of frm yr mnur (90 g pot -1 ) ws to h pot n thn mix with th soil. Th soil us in th tril h ph of 7.6, orgni ron (0.40%), vill nitrogn (170 Kg h -1 ), vill phosphorus (30 Kg h -1 ) n vill potssium (290 Kg h -1 ). Grounnut (Arhis hypog L.) ss of vrity JL-24 otin from MRS, UAS, Dhrw wr us in th tril. Th rommn os of frtilizr for grounnut (25:75:25 Kg NPK h -1 ) ws ppli. Nitrogn in th form of ur, phosphorus in th form of singl suprphospht n potsh in th form of murit of potsh wr ppli in lult quntitis t th tim of sowing. S inoultion n sowing Diss-fr, hlthy n ol ss of vr. JL-24 wr us for sowing in th pots. Nm k ws t th rt of 100 kg h -1 s pr th trtmnt shul. Cptn ws us t rt of 3 g kg -1 of ss to trt th s mtril for sowing n ths ss wr ot with lignit s Bryrhizoium t 300 g r -1 of s mtril. Four grounnut ss pr pot wr il. As pr th trtmnt tils, th ntgonist strins of tri (FPD-10 n FPD-15) wr inoult to th ss y ing 5 ml h on h s n thn ovr with soil. Th ultur of Trihorm hrzinum ws to th pots t th rt of 20 g Kg -1 of soil. Th osrvtions whih wr ror uring th trils inlu th numr of wilt slings up to hrvst, totl popultion of fluorsnt psuomons on th rhizopln n totl popultion of T. hrzinum in th rhizosphr soil wr ssss t 45 n 90 DAS. Th grounnut rop ws hrvst ftr 105 ys of sowing y uprooting th plnts n sprting th pos. Th totl numr of pos ws ount n thir wights ror. Th numr of inft pos ws ount n thir wights wr ror. Miroil ulturs us in th stuy Th tril ulturs us in th stuy wr otin from th Dprtmnt of Agriulturl Miroiology, UAS, Dhrw whil th fungl ulturs wr otin from th Dprtmnt of Plnt Pthology, UAS, Dhrw. Prprtion of gint ultur of Slrotium rolfsii Sn-orn ml mium ws us to prpr th gint ultur of Slrotium rolfsii S. It ws prpr y mixing 95 prts of sn with 5 prts of miz grits. Twnty kg sn-orn ml mium ws prpr n trnsfrr qully to thr ottls n striliz t 15 l prssur for 30 min. Th ottls wr inoult with frsh ultur of S. rolfsii n inut t 27 ± 1 C for 20 ys. Th ottls wr shkn vryy to gt uniform growth of S. rolfsii. This gint ultur ws us for th pot ultur xprimnt t th rt of 4% (w/w). Prprtion of Trihorm hrzinum ultur T. hrzinum ultur ws prpr y using wht rn n iogs spnt slurry. Both wht rn n iogs spnt slurry wr mix in qul proportions (1: 1). Th mixtur ws pl in ottl, moistn with wtr until it ws ompltly wt n thn striliz. Thr kilogrms of wht rn n iogs spnt slurry ws us. Th striliz ottl ws inoult with frsh ultur of T. hrzinum n inut t 30 C for 5 ys. Th ultur ws us t th rt of 20 g Kg -1 of soil in pot ultur trils. Prprtion of tril ntgonist strins Psuomons fluorsns FPD-10 n FPD-15 mintin on King s B gr mium (KBA) (King t l. 1954) wr multipli in flsks ontining 25 ml of King s B roth for 3 ys. Th popultion of FPD-10 n FPD-15 t th tim of sowing ws n fu ml -1, rsptivly. Enumrtion of totl fluorsnt psuomon popultion on th rhizopln Th plnts wr rfully uproot from th pots t 45 n 90 DAS without mging th root systm. Th soil hring to root systm ws islog n rins in stril tp wtr. Th root systm ws finlly wsh with stril istill wtr n ir ri. On grm of th smpl so otin ws ispns into 100 ml stril wtr lnk n shkn for 30 min on rotry shkr. Following sril ilution thniqu, iffrnt ilutions wr prpr n liquots of on ml wr plt for numrtion using KBA. Th plts wr inut t 30 C for 48 hrs n olony forming units wr ror. Enumrtion of Trihorm hrzinum popultion in th rhizosphr soil Th rhizosphr soil of grounnut rop ws ollt n th T. hrzinum popultion ws ssss y 10-fol sril ilution n plting on Trihorm sltiv gr mium (TSM). Th plts wr inut t 30 C n osrvtions wr ror ftr 7 ys of inution. Sttistil nlysis Trtmnts wr ssign to th xprimntl units (pots) in ompltly rnomiz sign with thr rplits. Smpling n msurmnts of vrious rspons vrils wr rri out t 45 n 90 ys ftr sowing (DAS). Frimn's Nonprmtri ANOVA ws ppli to tst th null hypothsis whn nlyzing th ount t on tril n fungl popultions. Th Bonfrroni follow-up prour ws us to ompr iffrnt trtmnts (Conovr n Imn 1981). Anlysis of vrin ws prform y running gnrl linr mol (GLM) prour of SAS. Th thrshol lvl of signifin us in F-tst ws P = Critil iffrn vlus wr lult whnvr th F-tst ws signifint. Th mns of iffrnt trtmnts wr ompr using prour LSMEANS of SAS. RESULTS Popultion of fluorsnt psuomons on th rhizopln of grounnut All th trtmnts riving inoultion of ithr FPD-10 or FPD-15 iffr signifintly ovr th untrt ontrol t 45 n 90 ys ftr sowing (DAS). Howvr, th popultion of fluorsnt psuomons in th rhizopln of roots tht riv ptn, nm k n T. hrzinum i not iffr signifintly whn ompr with th untrt ontrol t 45 DAS (Fig. 1). At 90 DAS, th trtmnt riving pplition of ptn ( fu g -1 root smpl) h signifintly highr popultion of fluorsnt psuomons thn th untrt ontrol plnt roots ( fu g -1 root smpl) (Fig. 1). Among th two fluorsnt psuomons, FPD-10 ws l to nhn th totl fluorsnt 34

3 Intgrt mngmnt of Slrotium rolfsii. Vikrm n Hmzhzrghni DAS 45 DAS CFU 10 5 /g root f f fg fghi ghi hi fgh i +NC+C+T Cp Trtmnts Fig. 1 Popultion of totl fluorsnt psuomons on th rhizopln of grounnut (CFU 10 3 /g root) inoult with Slrotium rolfsii t iffrnt growth stgs. Trtmnts with th sm lttr r not signifintly iffrnt t p = Trtmnts: +NC+C+T = FPD-15 + nm k + Cptn + T. hrzinum, = FPD-10 + nm k + Cptn + T. hrzinum, = FPD-10, = FPD-15, Cp = Cptn, N-C = nm k, = Trihorm hrzinum,, DAS = ys ftr sowing. N-C CFU 10 5 /g root f fg g h ij hi 90 DAS 45 DAS hi ij kl l l 0 N-C Cp +NC+C+T Trtmnts Fig. 2 Popultion of Trihorm hrzinum in th rhizosphr of grounnut (CFU 10 3 /g root) inoult with Slrotium rolfsii t iffrnt growth stgs. Trtmnts with th sm lttr r not signifintly iffrnt t p = Trtmnts: = Trihorm hrzinum, +NC+C+T = FPD-15 + nm k + Cptn + T. hrzinum, = FPD-10 + nm k + Cptn + T. hrzinum, = FPD-15, Cp = Cptn, = FPD-10, N-C = nm k,, DAS = ys ftr sowing. psuomon popultion ( fu g -1 root smpl) thn FPD-15 ( fu g -1 root smpl) t 45 DAS. FPD-10 inoult plnts h signifintly highr fluorsnt psuomon popultion thn FPD-15 inoult plnt roots t 90 DAS (Fig. 1). Th omintion of FPD-15 + Trihorm hrzinum + nm k + Cptn ( fu g -1 root smpl) rsult in highr fluorsnt psuomon olonis thn FPD-10 + Trihorm hrzinum + nm k + Cptn ( fu g -1 root smpl) ut thy i not iffr signifintly t 45 DAS. At 90 DAS, howvr, oth trtmnts h highr numr of fluorsnt psuomon olonis thn inoultion of FPD-10 n FPD-15 lon t 45 n 90 DAS (Fig. 1). Popultion of Trihorm hrzinum in th rhizosphr of grounnut Th popultion of T. hrzinum ws highst in th rhizosphr of plnts trt with T. hrzinum lon ( g -1 soil n g -1 soil t 45 n 90 DAS, rsptivly). Th inoultion of T. hrzinum lon, FPD-15 + Trihorm hrzinum + nm k + Cptn n FPD-10 + Trihorm hrzinum + nm k + Cptn gv signifint inrss in T. hrzinum popultion ovr untrt ontrol t 45 DAS n 90 DAS (Fig. 2). Th ntiv popultion of T. hrzinum in pots inrs from (t 45 DAS) to g -1 soil (t 90 DAS). Inoultion of FPD-10 n FPD-15 nourg th growth of T. hrzinum, ut not signifintly. Th soil riving th onsorti of ntgonists h intrstingly lowr T. hrzinum thn soils tht riv T. hrzinum lon (Fig. 2). Aition of nm k improv ntiv T. hrzinum popultion from to g -1 soil, ut th iffrn ws not signifint. Po wight pr plnt Th frsh wights of pos wr ror n it ws foun tht th po wight inrs in ss trt with ioontrol gnts n ptn. Among th trtmnts tst, inou- 35

4 Pst Thnology 5 (1), Glol Sin Books A Po numr plnt -1 B Po wight (g plnt -1 ) C % Inft pos plnt Agriulturl prtis urrntly r hmil intnsiv n urrny mning n this hmil intnsiv ntur hs rsult in xssiv n inisrimint rlin on oth pstii n frtilizr pplition n this in turn hs rsult in rsti hng in th soil strutur n hmil proprtis prt from rting pollution prolms. Sustinl griultur thrfor ims t intgrt us of ioontrol gnts, orgni mttr n hmil ontrol msurs. Hn th fsiility of using Psuomons fluorsns FPD-10 n FPD-15 long with Trihorm hrzinum, ptn n nm k in ontrolling Slrotium rolfsii ws stui n th rsults prtining to tht tril r isuss in this stion. In th prsnt tril mong th two fluorsnt psuomons, Psuomons fluorsns FPD-10 ws l to nhn th popultion of totl fluorsnt psuomons muh highr thn P. fluorsns FPD-15 t oth ys of smpling (45 n 90 DAS). In stuis onut rlir it hs n rport tht FPD-10 hs ttr potntil to oloniz grounnut roots thn FPD-15 (Ptil t l. 1998). Th popultion of introu ntgonisti strins FPD-10 n FPD-15 inrs rpily n rought own th numr of Slrotium rolfsii inft pos. In ition to tht ths strins of P. fluorsns inrs th numr n wight of pos signifintly ompr to th ontrol n othr trtmnts. Th ffiiny in inrsing th numr n wight of pos n rsing th prntg of inft pos ws signifintly ttr in FPD-10 trt plnts ompr to ll othr trtmnts. Similrly, whn P. ruginos ws ppli s s trtmnt, it rpily oloniz grounnut rhizosphr n ws l to ontrol ollr rot iss (Kishor t l. 2005). Th us of ithr P. fluorsns or Trihorm virns or Thirm lon or in omintion with h othr signifintly ru th stm rot us y S. rolfsii in grounnut plnts ompr to ontrol unr grnhous onitions (Mnjul t l. 2004). In nothr tril, pr-trtmnt of pnut ss with Billus sutilis prott pnut ss from th ngtiv fft of S. rolfsii n signifintly inrs growth prmtrs of pos ompr with th ngtiv ontrol (A-Allh 2005). S trtmnt of hik p ss with ithr P. fluorsns strin Pf4 n P. ruginos strin Pg, prott th fil grown plnts from S. rolfsii inftion (Singh t l. 2003). Th plnt mortlity rts wr signifintly lowr in triz ss ompr to untrt ontrol. Aysingh (2009) stui th ioontrol ffiy of Psuomons fluorsns CA05, Psuo h ltion of FPD-10 rsult in highst po yil (53.4 g), prominntly highr thn untrt ontrol (26.1 g). Inoultion of FPD-10 n FPD-15 ror signifintly highr po yil thn th plnts tht riv s trtmnt with ptn, ition of nm k n T. hrzinum (Fig. 3A). Intgrt ontrol with FPD-10 ror signifintly highr po yil (50.5 g) thn intgrt ontrol with FPD- 15 (48.9 g). Th onsorti prform signifintly ttr thn iniviul trtmnt with T. hrzinum, ptn n nm k with rgr to po yil (Fig. 3A). Po numr pr plnt g f +NC+C+T Th po numr pr plnt ws highst in plnts inoult with FPD-10 (26) follow y th trtmnt riving FPD T. hrzinum + nm k + Cptn (25). Th plnts inoult with FPD-10 h highr numr of pos pr plnt thn plnts tht wr inoult with FPD-15 n T. hrzinum lon. Th numr of pos ror from plnts inoult with FPD-10 iffr signifintly ompr to +NC+C+T +NC+C+T N-C N-C Trtmnts Fig. 3 Efft of pthogn ontrol gnts on yil prmtrs [A (po numr), B (po wight)] n iss svrity (C) of grounnut inoult with Slrotium rolfsii. Brs with th sm lttr r not signifintly (p 0.05) iffrnt from h othr. Trtmnts: Cp = Cptn,, = FPD-10, = FPD-10 + nm k + Cptn + T. hrzinum, +NC+C+T = FPD-15 + nm k + Cptn + T. hrzinum, = FPD-15, N-C = nm k, = Trihorm hrzinum. N-C Cp Cp Cp f plnts tht riv s trtmnt with ptn, ition of nm k n T. hrzinum (Fig. 3B). Th omintion of FPD-10 + T. hrzinum + nm k + Cptn (25) ror highr po numrs ompr to th trtmnt FPD-15 + T. hrzinum + nm k + Cptn (23) (Fig. 3B) ut thy i not iffr signifintly with h othr. Although th plnts trt with nm k ror highr po numrs pr plnt thn plnts trt with ptn n T. hrzinum, th iffrn ws not signifint (Fig. 3B). Prnt inft pos Th prntg of pos inft with S. rolfsii ws highst in th untrt ontrol trtmnt (87.5%) whil th lowst prntg of pos inft with S. rolfsii ws ror in plnts tht riv inoultion of FPD-10 (7.7%) follow y FPD-15 (12.5%) (Fig. 3C). Both FPD-10 n FPD-15 signifintly ru th prntg of inft pos ompr to th untrt ontrol, T. hrzinum, ptn n nm k. Although intgrt ontrol ontining tril strins, T. hrzinum, ptn, n nm k ru th prntg of inft pos, it ws signifintly lowr thn th rution of inftion rought out y FPD-10. Th intgrt pproh lso signifintly ru th prntg of inft pos s ompr to s trtmnt with ptn (Fig. 3C). DISCUSSION 36

5 Intgrt mngmnt of Slrotium rolfsii. Vikrm n Hmzhzrghni mons puti CA28 n Billus sutilis CA32 lon n in omintion ws tst ginst Rhizotoni solni n S. rolfsii unr grnhous onitions. Th R. solni n S. rolfsii popultions wr rmtilly ru ftr 30 ys of trnsplnting in tril trt pots ompr to th ontrols initing th ioontrol ility of ths rhizotri. H suggst tht omintion of B. sutilis with Psuomons strins n l to grtr plnt prottion ginst R. solni n S. rolfsii thn th ioontrol xhiit y ths strins whn thy wr us iniviully. Th mhnisms y whih ths fluorsnt psuomons n ll othr plnt growth promoting rhizotri ring out ioontrol hs n ttriut to th proution of sirophors (Pl t l. 2001), ntiiotis (Anjih t l. 1998; Pl t l. 2001), yni (Pl t l. 2000), lyti nzyms (Chrnin n Cht 2002) n omptition for inftion sits n nutrints (Mohm n Cuntr 1995) n inution of systmi rsistn in th host plnt (Liu t l. 1995). Th us of T. hrzinum lon lso signifintly ru th po inftion n improv th po yil ompr to th ontrol. Similrly, four isolts of Trihorm spp. signifintly ru th iss inin of stm rot of tomto plnts us y S. rolfsii in fil trils n inrs th yil ompr to ontrol (Chmswrng t l. 1992). In nothr grnhous tril, inoultion of mint plnts with ithr T. hrzinum or T. virns signifintly ru th ollr rot us y S. rolfsii n ws ompni y signifint inrs in hr n oil yil (Singh n Singh 2004). Applition of Trihorm spp. to pin slings rought out 57% rution in mping-off in pin slings us y S. rolfsii unr grnhous onitions (Wiystuti t l. 2003). Although th omintion of T. hrzinum, nm k n ptn long with ithr FPD- 10 or FPD-15 i not giv similr rsults s singl inoultions of FPD-10 or FPD-15, it i signifintly ru th po inftion us y S. rolfsii. Th pplition of T. hrzinum, ptn n nm s xtrt two ys ftr pthogn inoultion signifintly ru mping off iss us y S. rolfsii in grnhous grown tomto plnts (Okrk n Wokoh 2006). Th lvl of iss supprssion in thir stuis ws muh highr in T. hrzinum trt plnts ompr to ptn n nm s xtrt trt tomto plnts whih is similr to th rsults otin in our trils with grounnut plnts. In nothr stuy soil pplition of T. viri, P. fluorsns, nm k, T. viri + nm k, P. fluorsns + nm k signifintly ru th stm rot inin ompr to ontrol in grounnut plnts 60 ys ftr sowing (Krthikyn t l. 2006). Bosh t l. (2010) rport tht Trihorm spp. prov to th most fftiv ioontrol gnt ginst S. rolfsii n inhiit th growth of th pthogn y 80% unr in vitro onitions. Similrly, mutnts of Trihorm hrzinum 4572 signifintly ontroll th growth of S. rolfsii ompr to th wil typ strin in soyn plnts unr oth glsshous n fil onitions (Singh n Uphyy 2009). In nothr tril, ss of oth mungn n sunflowr pllt with onii of Trihorm hrzinum ru th inin of S. rolfsii n signifintly inrs plnt hight of oth mungn n sunflowr plnts ompr to ontrol n othr ntgonists (Yqu n Shhz 2008). Th improv ntiv popultion of T. hrzinum osrv u to inoultion of FPD-10 n FPD-15 inits positiv intrtion. Th trtmnts riving pplition of T. hrzinum signifintly ru th inftion us y S. rolfsii n ru th numr of inft pos. Similr rsults of signifint rutions in th tivity of S. rolfsii y trtmnt of pnut plnts with T. hrzinum hv n rport rlir in othr stuis (Muthmiln n Jyrjn 1996; Gnsn n Skr 2004; Gnsn t l. 2007). Th trtmnt riving pplition of T. hrzinum in this tril signifintly improv th yil prmtrs of pnut. Similrly, th pplition of T. hrzinum signifintly inrs th growth n yil prmtrs of pnut rop ompr to th ontrol (Gnsn t l. 2007). Th mhnisms involv in inhiition of pthogns y ioontrol gnts r mor omplx n it vris with ntgonist, pthogn n th host whih r involv in th intrtion. Howvr, th mhnisms r fft y soil typ, tmprtur, ph, plnt moistur, soil nvironmnt n prsn of othr mmrs of soil miroflor. Th i of using svrl ioontrol gnts, hmils n orgni mnmnts with svrl mhnisms of ontrol fits in wll with th onpts of intgrt pst mngmnt whrin svrl mns of iss supprssion r ppli onurrntly. In this snrio whn on or mor mns/mhnisms r not fftiv th othrs will ompnst for th sn of th formr mhnism (Gutsky t l. 2002). Stuis onut rlir hv suggst using mor thn on typ of iognt for th mngmnt S. rolfsii in ition to using oth hmil n io gnt tools for its ttr mngmnt (Plih t l. 2007). It is suggst tht furthr srning of ths PGPR strins for ioontrol potntil of othr plnt pthogns might onfirm th rng of ioontrol tivity. Fil xprimnttions to onlusivly prov th ioontrol potntil of FPD-10 n FPD-15 in ition to tst ll othr trtmnts r nssry for thir ommril xploittion. REFERENCES A-Allh EF (2005) Efft of Billus sutilis Isolt on Southrn Blight (Slrotium rolfsii) n lipi omposition of pnut ss. Phytoprsiti 33, Aysingh S (2009) Effiy of omin us of ioontrol gnts on ontrol of Slrotium rolfsii n Rhizotoni solni of Cpsium nnuum. Arhivs of Phytopthology n Plnt Prottion 42, Anjih V, Kom N, Nowk-Thompson B, Lopr JE, Höft M, Tmong JT, Cornlis P (1998) Involvmnt of phnzins n nthrnilt in th ntgonism of Psuomons ruginos PNA1 n Tn5 rivtivs towr Fusrium spp. n Pythium spp. Molulr Plnt-Miro Intrtions 11, Bosh O, Iglk CA, Omorusi VI (2010) In vitro miroil ontrol of pthogni Slrotium rolfsii. Intrntionl Journl of Agriultur n Biology 12, Brown RG (1999) Disss of rl rops n nnul oil s rops. In: Brown RG (E) Plnt Disss n thir, Srup n Sons, Nw Dlhi, pp Chmswrng C, Sngkh K, Ktprsr N (1992) Fil plot srning of ntgonisti fungi us for ioontrol of tomto root n stm rot us y Slrotium rolfsii. Kstsrt Journl 26, Chrnin L, Cht I (2002) Miroil nzyms in ioontrol of plnt pthogns n psts. In: Burns RG, Dik RP (Es) Enzyms in th Environmnt: Ativity, Eology, n Applitions, Mrl Dkkr, Nw York, pp Cook K (1991) Miroil inoulnts in griultur. Shll Agriultur 9, Conovr WJ, Imn RL (1981) Rnk trnsformtions s rig twn prmtri n nonprmtri sttistis. Amrin Sttistiin 35, Dfrits JR, Grmi JJ (1990) Plnt growth promoting rhizotri for wintr wht. Cnin Journl of Miroiology 36, Dy R, Pl KK, Bhtt DM, Chuhn SM (2004) Growth promotion n yil nhnmnt of pnut (Arhis hypog L.) y pplition of plnt growth-promoting rhizotri. Miroiologil Rsrh 159, Duffy B (2000) Comintion of pnyuron n Psuomons fluorsns strin 2 79 for intgrt ontrol of rhizotoni root rot n tk-ll of spring wht. Crop Prottion 19, Gnsn S, Kuppusmy RG, Skr R (2007) Intgrt mngmnt of stm rot iss (Slrotium rolfsii) of grounnut (Arhis hypog L.) using Rhizoium n Trihorm hrzinum (ITCC-4572). Turkish Journl of Agriultur n Forstry 31, Gnsn S, Skr R (2004) Bioontrol mhnism of grounnut (Arhis hypog L.) isss-trihorm systm. In: Pth GR, Gol PK (Es) Biothnologil Applitions in Environmnt n Agriultur, ABD Pulishrs, Jipur, Ini, pp Gutsky R, Shtinrg D, El Y, Fishr E, Dinoor A (2002) Improving iologil ontrol y omining ioontrol gnts h with svrl mhnisms of iss supprssion. Phytopthology 92, H NT (2010) Using Trihorm spis for iologil ontrol of plnt pthogns in Vitnm. Journl of th Intrntionl Soity for Southst Asin Agriulturl Sins 16, Jtiynon K, Kloppr JW (2002) Mixturs of plnt growth promoting rhizotri for inution of systmi rsistn ginst multipl plnt isss. Biologil 24, Krthikyn V, Snkrlingm A, Nkkrn S (2006) Biologil ontrol of grounnut stm rot us y Slrotium rolfsii (S.). Arhivs of Phyto- 37

6 Pst Thnology 5 (1), Glol Sin Books pthology n Plnt Prottion 39, King EO, Wr MK, Rny DE (1954) Two simpl mi for monstrtion of pyoynin n fluoroin. Journl of Lortory n Clinil Miin 44, Kishor GK, Pn S, Poil AR (2005) Biologil ontrol of ollr rot iss with ro-sptrum ntifungl tri ssoit with grounnut. Cnin Journl of Miroiology 51, Konoh M, Hiri M, Sho M (2001) Intgrt iologil n hmil ontrol of mping-off us y Rhizotoni solni using Billus sutilis RB14-C n flutolnil. Journl of Biosin n Bionginring 91, Liu L, Kloppr W, Tuzun S (1995) Inution of systmi rsistn in uumr ginst Fusrium wilt y PGPR. Phytopthology 85, Mnjul K, Kishor GK, Girish AG, Singh SD (2004) Comin pplition of Psuomons fluorsns n Trihorm viri hs n improv ioontrol tivity ginst stm rot in grounnut. Plnt Pthology Journl 20, My CD, Dtr VV (1988) Disss of grounnut in th tropis. Rviw of Tropil Plnt Pthology 5, Mohm S, Cuntr IG (1995) Isoltion n hrtriztion of Psuomons fluorsns strin supprssiv to Bipolris myis. Journl of Phytopthology 143, Muthmiln M, Jyrjn (1996) Intgrt mngmnt of Slrotium root rot of grounnut involving Trihorm hrzinum, Rhizoium n rnzin. Inin Journl of Myology n Plnt Pthology 26, Okrk VC, Wokoh RC (2006) Effts of som tropil plnt xtrts, Trihorm hrzinum n ptn on th mping-off iss of tomto inu y Slrotium rolfsii. Agriulturl Journl 1, Ozgonn H, Akgul DS, Erkili A (2010) Th ffts of rusulr myorrhizl fungi on yil n stm rot us y Slrotium rolfsii S. in pnut. Afrin Journl of Agriulturl Rsrh 5, Pl KK, Tilk KV, Sxn AK, Dy R, Singh CS (2000) Antifungl hrtristis of fluorsnt Psuomons strin involv in th iologil ontrol of Rhizotoni solni. Miroiologil Rsrh 155, Pl KK, Tilk KV, Sxn AK, Dy R, Singh CS (2001) Supprssion of miz root isss us y Mrophomin phsolin, Fusrium moniliform n Fusrium grminrum y plnt growth promoting rhizotri. Miroiologil Rsrh 156, Plih P, Aivr SS, Kumr O, Chnrpp D, Jngni S (2007) Snsitivity of Slrotium rolfsii s. isolts to iffrnt grohmil n ulturl filtrts of io-gnts. Krntk Journl of Agriulturl Sins 20, Ptil R, Jgsh K, Krishnrj PU, Kulkrni JH (1998) Btriztion of grounnut with Psuomons fluorsns for th ontrol of ollr rot us y Slrotium rolfsii S. Krntk Journl of Agriulturl Sins 11, Poil AR, Kishor GK (2002) Biologil ontrol of pnut isss. In: Gnnmnikm SS (E) Biologil of Crop Disss, Mrl Dkkr, Nw York, pp Punj ZK (1988) Slrotium (Athli) rolfsii pthogn of mny plnt spis. In: Sihu GS (E) Avns in Plnt Pthology (Vol 6) Gntis of Plnt Pthogni Fungi, Ami Prss, Lonon, pp Singh UP, Srm BK, Singh DP (2003) Efft of plnt growth-promoting rhizotri n ultur filtrt of Slrotium rolfsii on phnoli n sliyli i ontnts in hikp (Cir ritinum). Currnt Miroiology 46, Singh A, Singh HB (2004) of ollr rot in mint (Mnth spp.) us y Slrotium rolfsii using iologil mns. Currnt Sin 87, Singh BK, Uphyy RS (2009) Mngmnt of southrn stm light of soyn y PCNB rsistnt mutnts of Trihorm hrzinum 4572 init y Slrotium rolfsii. Journl of Agriulturl Thnology 5, Wiystuti SM, Sumri H, Yunirti D (2003) Biologil ontrol of Slrotium rolfsii mping-off of tropil pin (Pinus mrkusii) with thr isolts of Trihorm spp. Onlin Journl of Biologil Sins 3, Yqu F, Shhz S (2008) Efft of s pllting with Trihorm spp., n Gliolium virns on growth n oloniztion of roots of sunflowr n mung n y Slrotium rolfsii. Pkistn Journl of Botny 40,