Allelopathic effect of legumes leachates on seed germination and seedling growth of maize (Zea mays L.)

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1 Journl of Agriulturl ehnology 2013 Vol. 9(4): Journl of Agriulturl Aville ehnology online , Vol. 9(4): ISSN Allelopthi effet of legumes lehtes on seed germintion nd seedling growth of mize (Ze mys L.) Muhmmd Ayu, Muhmmd Shehzd *, M. Shhid Siddique, M.A. Ndeem nd M. hir Deprtment of Agronomy, University of Agriulture, Fisld-Pkistn Muhmmd Ayu, Muhmmd Shehzd, M. Shhid Siddique, M.A. Ndeem nd M. hir (2013) Allelopthi effet of legumes lehtes on seed germintion nd seedling growth of mize (Ze mys L.). Journl of Agriulturl ehnology 9(4): In Pkistn, the trend to grow forge mize in mixture with legume forges for improving yield nd qulity is inresing ut llelopthi effets of legumes on germintion of mize nd seedling growth re not known. herefore, lortory experiments to investigte the llelopthi effets of queous s of nd stems of leguminous rops viz., owpe, sesni, mungen nd luster en on seed germintion, seedling growth of mize were onduted in the Deprtment of Agronomy, University of Agriulture, Fisld, Pkistn, during the yer he plnts: mungen, owpe, luster en nd sesni were seprted into nd stems nd soked individully in wter t the rte of 100g per liter of wter for 24 hours nd the queous of nd stems were otined y filtering wter through sieve. Lehte of leguminous rops showed inhiitory effets on germintion nd emergene, shoot nd root length, fresh nd dry weight of shoots nd roots nd totl fresh weight of seedlings, MG, GI nd 50. here hs lso een vrition in llelopthi effet of stems nd nd even differenes were signifint in some prmeters etween stems nd of sme legumes. Sesni nd stem s hve more pronouned effet on shoot length nd root length thn s of other legumes rops. Key words: Aqueous lehtes, germintion/emergene, mung en, owpe, luster en, sesni nd mize Introdution Allelopthy n simply e defined s the ility of plnts to inhiit or stimulte growth of the other plnts in the environment y exuding hemils. Cover rops, suh s legumes suppress weeds in orn nd inrese grin yield (White nd Worshm, 1990; Johnson et l., 1993; Yenish et l., 1996). Ashrfi et l. (2008) reported tht rley (Hordeum vulgre) ontins wtersolule llelohemils tht inhiit the germintion nd growth of other rops speies nd weeds. Rye s over rop used signifint redution in density nd * Corresponding uthor: Muhmmd Shehzd; e-mil: m.shhzduf@gmil.om 863

2 iomss of severl weed speies in orn nd soyen (Glyine mx L.) (esdle et l., 1996; Liel et l., 1992). he effet of over rops to suppress weeds n e ttriuted to their ility to relese toxi sustnes in the environment nd to rete n unfvourle environment for weed germintion nd estlishment. Mihel nd Crlene (2007) reported phytotoxiity of queous folir lehtes nd ground dried residues of sunhemp (Crotlri june L.), owpe (Vign unguiult L.) nd velveten (Muun deeringin) on rop nd weed germintion. here is wide vrition in the ility of ultivrs of trp rops to redue the germintion nd growth of S. hermonthi y relesing llelohemils (Ali, 2000). Chon nd Kim (2004) found tht rie (Oryz stiv L.), rley (Hordeum vulgre), whet (ritium estivum L.), nd ot (Aven stiv L.) relese toxi sustnes in the environment either through root exudtion or dey of their plnt residues. Borner (1960) lso indited tht old wter lehtes of rley, rye, nd whet strws s well s loholi lehtes of roots ontin phenoli ompounds, toxi to plnt growth, wheres Shresth et l. (2002) reported tht soyen yield ws inresed y the presene of rye nd orn used s over rops. Similrly, Swnton et l. (1999) lso found tht orn yield ws inresed y rye over rop. Irshd nd Cheem (2006) showed tht sorghum lehte deresed rnyrd grss dry weight 31-48%. he tree E. mldulensis, Prosopis juliflor, nd Ai niloti, signifintly ffeted seed germintion nd seedling growth of severl rops nd/or weed speies (Khn et l., 2004; khn et l. 2007). Hedge nd Miller (1990) reported tht lflf (Medigo stiv L.) plnts ontin wter-solule sustnes tht re utotoxi s well s llelopthi to other plnts. Different plnt prts vried in their llelopthi effets on the germintion nd seedling growth of rops plnts. Some plnts prts hve more inhiitory effet thn other (Burhn nd Shukt, 1999; nveer et l., 2008). Rhimi et l. (2006) evluted the llelopthi responses of P. psyllium upon germintion nd growth stges of redroot pigweed (Amrnthus retroflexus), wild rley (Hordeum leporinum), lk mustrd (Brssi nigr) nd Lmsqurters (Chenopodioum lum L.) nd results showed tht queous shoot lehte, shoot residue nd simultneous growth of P. psyllium displyed the most onsistent negtive effets on germintion nd dry mtter of trget plnts. Shoot residue signifintly deresed height nd dry mtter of ll trget speies exept for wild rley. In Pkistn, trend of growing forge mize in mixture with forge legumes is inresing. Most of previous studies hve indited tht llelohemils of rops hve the ility to suppress weeds seed germintion nd ffet rop yields, ut informtion out the llelohemil effets of 864

3 Journl of Agriulturl ehnology 2013, Vol. 9(4): summer legume rops on seed germintion, seedling emergene nd growth of mize rop re lking. he present study therefore, ws onduted to ssess the llelopthi potentil of nd stem of some summer legume rops on seed germintion, seedling emergene nd growth of mize. Mterils nd methods Lortory sed experiments to evlute the llelopthi effets of oth nd stems lehtes of four legumes i.e. mung en, owpe, luster en nd sesni on seed germintion, emergene nd seedling growth of mize, were onduted in Deprtment of Agronomy, University of Agriulture, Fisld during Field grown plnts of ll legumes t pod development stge were tken nd dried t room temperture. After drying, nd stems were seprted nd smll piees were mde with help of sissors. Dried piees of nd stems were immersed in tp wter seprtely in the rtio of 1:10 (w/v) t room temperture for 24 hours. he lehtes of nd stems were otined y filtering wter through sieve (0.4mm). Distilled wter s (ontrol) ws lso inluded for omprison. Experiment: 1 In this experiment, ten seeds of mize were pled evenly on filter pper (Whtmn No.10) in petri pltes. Leves nd stem lehte of legumes mesuring 4ml ws dded to petri pltes ording to tretments. Petri pltes were pled t room temperture rnging from 25 to 30 ºC. During this study petri pltes were oserved dily nd wter or lehte ws pplied if needed. Experiment: 2 In this experiment, ten seeds of mize were sown in snd filled plsti pots (16m in dimeter). Leves nd stem lehte of legumes ws dded to plsti pots ording to tretment. Pots were pled t room temperture (25-30 ºC) for 15 dys. During this study pots were oserved dily nd wter or lehte ws pplied if needed. After 15 dys, seedling were removed nd wshed with wter. he root nd shoot length ws mesured with mesuring tpe. Proedure for Reording the Oservtions Seed Germintion he seeds were onsidered s germinted when the rdile ws of 2 mm long. 865

4 he germinted seeds were ounted fter 24 hours regulrly for fourteen dys nd germinted seeds were disrded every dy. ime to Strt Germintion/Emergene ime to strt germintion/emergene ws reorded s when first seed strted to germinte in petri pltes or emerge out from soil in plsti pots. Germintion Perentge Germintion %ge ws lulted y the formul given elow for eh tretment in eh replition: Germintion %ge = Germinted Seeds/ otl seeds 100 Men Germintion ime (MG) Men emergene time (MG) ws lulted y using the eqution given y Ellis nd Roerts (1981). ime to 50% Germintion ( 50 ) ime tken to 50 % emergene of seedlings ( 50 ) ws lulted ording to the formule of Cooler et l. (1984) nd modified y Frooq et l. (2005). Germintion Index (%) he germintion index (GI) ws lulted s desried in the Assoition of Offiil Seed Anlysts (AOSA, 1983). otl Weight (g) After wshing seedlings, they were dried for while. he seeds were removed nd whole plnt ws weighed y using eletri weighing lne. Shoot nd Root Length Shoot were seprted from roots y using sissors nd then shoot length nd root length ws mesured y using sle. 866

5 Journl of Agriulturl ehnology 2013, Vol. 9(4): Fresh Weight of Shoots nd Roots (g) Roots nd Shoots were weighed seprtely y using eletri weighing lne. Dry Weight of Shoots nd Roots (g) Roots nd shoots were dried seprtely in n oven t 80 ºC to onstnt weight nd the weight ws determined y using eletri lne. Sttistil nlysis he dt olleted were nlyzed sttistilly y using the Fisher s nlysis of vrine tehnique y using MSA-C sttistil omputer pkge nd Lest Signifint Differene est t 5% proility ws used to ompre the tretment mens (Steel et l., 1997). Experiment: I Allelopthi Effet of Legumes Lehtes on Mize Germintion nd Growth ime to strt germintion (SG) [dys] he dt presented in (le 1) showed signifint effet of legumes lehtes on time to strt germintion in mize. he legumes lehte tretments of oth nd stem signifintly took more time to germinte thn ontrol tretment. he mximum numers of dys (6.00) were reorded in tretment 4 ( 4 ) where owpe stem lehte ws pplied. However, it did not differ signifintly in 2, 5, 6, 7, 8 nd 9. Mung en hve minimum effet on time to strt germintion. Dt regrding the effet of legume lehtes on time to strt emergene (pot experiment) in mize is presented in le 1. All tretment hving legumes lehte either from stems or signifintly took more time to emerge thn ontrol. he mung en hve minimum ffet on time to strt emergene. In pot experiment, mximum time (8.25 dys) to strt emergene of mize ws reorded in tretment 4 (ow pe stem lehte) nd minimum time (2.75 dys) to strt emergene ws reorded in ontrol tretment. Khn et l. (1999) nd Khn et l. (2007) hve lso reported tht lef lehte delyed the germintion of mize. 867

6 le 1. Allelopthi Effet of Legumes Extrts on Mize Germintion nd Emergene retments Control (distilled wter) Mung en stem Mung en Cow pe stem Cow pe Sesni stem Sesni Cluster en stem Cluster en ime to strt germintion Petri E d PotE Petri E de 62.5 de e 70.0 e G % MG (Dys) 50 (Dys) GI PotE d d Petri E Pot E. Petri E. Pot E. Petri E. Pot E d d LSD Germintion/emergene perentge Some legume lehtes signifintly deresed the germintion perentge of mize s ompred to ontrol tretments (le 1). he lowest germintion (57.50%) ws reorded in 3 where owpe lef-lehte ws pplied nd the mximum germintion (100 %) ws reorded in ontrol tretment ( 1 ). he differenes mong ontrol, sesni nd luster en stem lehte were not signifint. he sesni lef-lehte hve lest effet on germintion perentge. Cowpe lef-lehte hve mximum inhiitory effet on germintion perentge of mize. Similrly, in pot experiment, emergene (%) of seedlings ws redued signifintly y lmost ll legume lehtes (le 1). he minimum emergene (45%) ws found in 4 where ow pe stem lehte ws pplied. Mximum vlue of emergene (100.0%) ws reorded in ontrol tretment nd it differs signifintly from mung en lef-lehte tretment. Signifint redution in seedling emergene hs lso een reported y Sumn et l. (2002). hey found tht hikpe seeds lehtes inhiit seed emergene % of sugrne rop. he oservtions indite relese of inhiitory sustnes

7 Journl of Agriulturl ehnology 2013, Vol. 9(4): from legumes plnt oth from nd stems tht inhiited emergene perentge. ime to 50% germintion ( 50 ) [dys] he dt presented in le 1 showed signifint effets of legume lehtes on time to 50% emergene of mize. Both stems nd lef-lehtes of legumes took more time to ttin 50 thn ontrol tretment. Mximum time (5.00 dys) to omplete 50 ws reorded in 3 where mungen lef-lehte ws used nd it did not differ signifintly from lusteren nd stem lehtes tretment. Minimum numers of dys (0.62 dys) were reorded in ontrol tretments ( 1 ) to omplete 50. In pot experiment, mximum time (7.75 dys) to omplete 50 ws reorded in tretment 9 where lusteren lef-lehte ws pplied (le 1). Minimum numers of dys (1.37 dys) were oserved in the ontrol tretment ( 1 ). However, differenes mong 1, 4 nd 5 were not signifint. hese results re in ordne with those of Chon nd Kim (2004), who reported tht llelopthy my vry mong plnt prts. Sng et l. (2004) lso reported tht llelohemils present in plnt inrese the time to 50% germintion s ompred to ontrol in lflf plnt. Men germintion time (MG) [dys] Men germintion time of mize rop ws lso ffeted y the stems nd lef-lehtes of legumes (le-1). All lehte- tretments hve high MG s ompred to ontrol in pot experiment. Mximum MG (7.47dys) ws reorded in 3 where mungen lef-lehte ws pplied. he lowest vlue of MG (3.68 dys) ws reorded in ontrol tretment ( 1 ). In pot experiment (le1), MG ws lso influened signifintly. All those tretment where lehte of legumes were pplied, MG ws signifintly more thn the ontrol, eing mximum in lusteren lef-lehte nd sesni stem lehte (9.77 dys). he tretments: 2, 4, 5, 6, 7, 8 nd 9 hve sttistilly similr men germintion time. Similr results were reported y Mihel nd Crlene (2007). Germintion Index (GI) All legume lehte tretments signifintly redued the germintion index (le 1). Mximum vlue of GI (7.80) ws noted in ontrol tretment ( 1 ) nd minimum vlue of GI (3.25) ws reorded in tretment where luster 869

8 Length en lef-lehte ( 9 ) ws pplied nd it did not differ signifintly from 4, 5 nd 6. In pot experiment GI ws lso redued y ll lehte tretments s ompred to ontrol (le 1). Mximum vlue of GI (6.25) ws reorded in ontrol tretment nd minimum vlue of GI (1.24) ws found in 4 where owpe stem lehte ws pplied. hese results re supported y the findings of Shhid (2010). Experiment: II Allelopthi effet of legumes lehtes on mize seedling nd growth Shoot length of seedlings (m) he lehtes from stems nd of legumes used signifint redution in shoot length of mize (Fig. 1). he lef-lehtes of sesni showed more inhiitory effet on shoot length of mize seedlings s ompred to ll other lehtes of legumes. Mximum shoot length 8.55 m ws reorded in ontrol tretment ( 1 ) nd minimum vlue (2.32 m) ws reorded in 7 where sesni ws pplied. hese results re supported y the findings of Shukl et l. (2003). hey lso reported redution in seedling height in plnts reeiving llelohemils. Shoot (SL)nd Root length (RL) Control Mung en stem Mung en Cow pe stem Cow pe Sesni stem Sesni Cluster en stem Cluster en SL RL retments Fig. 1. Allelopthi effet of stems nd of different legumes on Shoot (SL) nd Root () length of mize seedlings Root length (m) he lehtes from stems nd of legume rops lso used signifint redution in root length s ompred with the seedlings rised in distilled wter (Fig. 1). he lef-lehtes of sesni showed more inhiitory effet on root length of mize seedling s ompred to ll other lehtes of 870

9 Weight Journl of Agriulturl ehnology 2013, Vol. 9(4): legumes. Mximum root length (7.27 m) ws reorded in ontrol tretment ( 1 ) nd minimum length of roots (0.88 m) ws reorded in 7 where sesni lef-lehte ws pplied. retments 3, 5 nd 8 were sttistilly similr to one other. hese results re in greement with the findings of Chung nd Miller (1995) they reported tht wter lehtes of llelopthi plnts signifintly redued the growth of roots. Fresh weight of Shoots Dt regrding the effet of legume rop lehtes on fresh weight of shoots of mize seedlings (Fig. 2) showed tht ll lehtes either or stems redued the fresh weight of mize seedlings s ompred to ontrol tretment. Mximum fresh weight (0.54g) per seedling ws reorded in ontrol tretment nd minimum (0.10g) per seedling ws reorded in tretment 8 where luster en stem lehte ws pplied. Derese in fresh weight of shoot y llelohemils hs lso een reported y Nelson (1996). Fresh weight of shoots(fws) nd roots(fwr) nd totl fresh weight(fw) Control Mung en stem Mung en Cow pe stem Cow pe Sesni stem Sesni Cluster en Cluster en stem FWS FWR FW Retments Fig. 2. Allelopthi effet of stems nd s of different legumes on fresh weight of shoots (FWS), fresh weight of Root (FWR) nd totl fresh weight (FW) of mize seedlings Fresh weight of Roots (g) Fresh weight of roots of seedling ws lso ffeted signifintly y lehtes of leguminous rops s ompred to ontrol tretment (Fig. 2). All legume lehte either from stems or root signifintly redued the fresh weight of roots. Sesni lef-lehte remin t pr with owpe lef-lehte produed minimum fresh weight (0.005g) of roots. he differenes mong mung en stem lehte; owpe stem lehte, owpe lef-lehte; luster en stem lehte nd luster en lef-lehte were not signifint. 871

10 Mximum fresh weight (0.31 g) of roots ws reorded in ontrol. Ali (2000) hve lso reported tht owpe lehte redued the fresh weight of root rops nd weeds. otl fresh weight of seedlings (g) he dt presented in Fig. 2 showed tht the totl fresh weight of seedlings ws influened signifintly y the tretment under study. Weight of seedlings of mize grown in different lehtes ws signifintly redued ompred to ontrol tretment. Mximum fresh weight (0.84 g) of seedling of mize ws reorded in ontrol tretment nd minimum (0.16 g) ws reorded in tretment 7 where sesni lef-lehte ws pplied. he differenes mong the 7, 8 nd 9 were not signifint. Hedge nd Miller (1990) hve lso reported redution in fresh weight per plnt of lflf nd fresh weight per plnt of mize. Dry weight of Shoots (g) Dt presented in (Fig-3) showed tht llelopthi effet of legumes lehtes on dry weight of shoots of mize seedlings ws signifint. All lehte either from stem or signifintly redued the dry weight of mize seedling. Minimum dry weight of shoot (0.03g) ws reorded in 8 where luster en stem lehte ws pplied nd mximum (0.41g) dry weight of shoots ws reorded in ontrol tretment. he differenes mong the lehte tretment were not signifint exept owpe lef-lehte, whih hve signifintly higher dry weight of shoots thn ll other lehte tretments. Signifint redution in dry weight of rnyrd grss hs een reported y pplying lehte of mize y Irshd nd Cheem (2006). Ashrfi et l. (2008) lso reported tht lehte from sunflower redued the dry weight of wild rley seedlings. Dry weight of Roots (g) Dt presented in Fig. 3 showed signifint differenes mong the tretments regrding the dry weight of roots of mize. he ontrol tretment ( 1 ) gve signifint higher dry weight of roots thn stems nd lef-lehte tretment of legumes. he minimum dry weight (0.002g) ws reorded in 7 where sesni lef-lehte ws pplied. Redution in dry weight of roots of rops due to llelopthi effet of rops hs lso een reported y Rhimi et l. (2006). Jeen nd Ahmd (2009) lso reported tht llelohemils from weeds redued the fresh nd dry weight of roots of mize rop. 872

11 Journl of Agriulturl ehnology 2013, Vol. 9(4): Control Dry w eight of shoots (DWS), dry w eight of Roots(DWR) nd totl dry weigt (DW) Mung en stem Mung en Cow pe stem Cow pe Sesni stem Sesni Cluster en stem Cluster en DWS DWR DW Fig. 3. Allelopthi effet of stems nd s of different legumes on dry weight of shoots (DWS), dry weight of Root (DWR) nd totl dry weight (DW) of mize seedlings otl dry weight of seedlings (g) he totl dry weight of mize seedling ws redued y ll legume s s ompred to ontrol tretment s shown in Fig. 3. Mximum dry weight of mize seedlings ws reorded in ontrol tretment (1) nd mung en redued the dry weight of mize seedlings. All other s tretment signifintly redued the dry weight of mize seedlings s ompred ontrol. Conlusion It n e onluded from the results tht lehte of ll nd stems of ll legumes rops tht suppressed germintion nd growth of mize seedlings. Referene Ali, M.O. (2000). Development of suppressive ropping systems for Strig hermonthi in the moist svnn through soyen (Glyine mx (L.)) Merr. Ph.D. hesis, University of Idn, Nigeri. Ashrfi, Z.Y., Sdeghi, S., Mshhdi, H.R. nd Alizde, H.M. (2008). Study of llelopthil effets of rley on inhiition of germintion nd growth of seedling of green foxtil. J. SA Agri. Res. 6:1-6. Assoition of Offiil Seed Anlysis (AOSA). (1983). Seed Vigor esting Hndook. Contriution No. 32 to the hndook on Seed esting. Borner, H. (1960). Liertion of orgni sustnes from higher plnts nd their role in soil sikness prolems. Bot. Rev., 26:

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