Differential Performance of Lowland Rice Cultivars for Phosphorus Uptake and Utilization Efficiency under Hydroponic and Soil Conditions

Transcription

1 INTERNATIONAL JOURNAL OF AGRICULTURE & BIOLOGY ISSN Print: ; ISSN Onlin: /1x/ DOI: /IJAB/ Full Lngth Artil Diffrntil Prformn of Lowln Ri Cultivrs for Phosphorus Uptk n Utiliztion Effiiny unr Hyroponi n Soil Conitions Muhmm Irfn 1,*, Triq Aziz 1,3, Muhmm Amr Mqsoo 1, Hfiz Muhmm Bill 1, Wqs-u-Din Khn 4 n Nsr Rsh 1 1 Institut of Soil n Environmntl Sins, Univrsity of Agriultur, Fisl-384, Pkistn Soil n Environmntl Sins Division, Nulr Institut of Agriultur, Tnojm-76, Pkistn 3 Th UWA Institut of Agriultur n Shool of Agriultur n Environmnt, Th Univrsity of Wstrn Austrli, Prth, WA- 61, Austrli 4 Sustinl Dvlopmnt Stuy Cntr, Govrnmnt Collg Univrsity, Lhor, Pkistn * For orrsponn: irfn1513_uf@yhoo.om Astrt Exploiting th gnti vritions in rop plnts for nhn P ffiiny sms invitl for sustining rop proutivity on su-optiml P supplying gro-osystms. Howvr, vrition in growth mium us for srning grmplsm is mjor onstrint for poor unrstning of th P ffiiny mhnisms. In prsnt stuis, lowln ri ultivrs wr vlut for P utiliztion ffiiny (PUtE) s on shoot ry mttr (SDM) n py yil unr hyroponi n soil onitions. Rsults rvl tht P fiiny signifintly ru SDM, py yil n P uptk unr oth growing nvironmnts. Root pth, root-shoot rtio n root ry mttr (RDM) ws nhn in ll ultivrs ut t vrying rts in rspons to P fiiny. Ri ultivr Bsmti- prou mximum SDM n py yil unr qut n fiint P lvls. Root DM orrlt signifintly with SDM (r =.7) n shoot P uptk (r = 68) initing implitions of improv root growth for P quisition unr P fiiny. Ri ultivrs xhiit wi ivrsity for PUtE s on SDM n py yil. Th highst rspons to P ition ws ovious in ultivr KSK-8 unr hyroponi n in IR-6 unr soil onitions s init y thir highr strss ftors (i.. 48 n 49%). Th rsults suggst tht lrg vritions xist mong ri ultivrs to tolrt P fiiny s wll s thir rspons to P frtiliztion. Morovr, th iffrntil prformn of ultivrs for iomss proution n PUtE unr hyroponi n soil onitions signifi tht spil onsirtion must pi to growing mium whil srning ri for P ffiiny. 19 Frins Sin Pulishrs Kywors: Oryz stiv L; Py yil; Root-shoot rtio; Strss ftor; Utiliztion ffiiny Introution Phosphorus is vitl onstitunt for norml plnt growth n vlopmnt n is mong th mjor rivrs for glol rop proutivity (Stwrt t l., 5). It is typil rly-prio nutrint whos qut lvl in rooting mium must mintin uring rly rop growth stg for optiml yils. Its fiiny is rport to limit rop yils on mor thn 3% of ultivt soils worlwi (Vn t l., 3). Th sustinility of ropping nvironmnts mns th mintnn of qut P lvl in soil solution through th ition of orgni n/or inorgni P sours (Irfn t l., 16, 18). Th ffiiny of n/or ntiv soil P is sriously low on lrous soils us only smll portion (1-3%) of ppli P is utiliz y plnts in first growing sson (Brtrn t l., 3). Morovr, th vrg glol P us ffiiny for rl rops is vry low n is stimt upto 16% only from 1961 to 13 (Dhillon t l., 17). By som stimts, phospht rok rsrvs my plt y 5, thus foring th n for nhn ffiiny of P sours (Vn t l., 3). Th fiiny of P is srious onrn in lklin lrous soils of Mitrrnn sin s wll s highly wthr soils of tropis n sutropis (Korkmz t l., 9). It my pripitts or sor on iron n luminum oxis in ii soils or forms sonry minrls of lium n mgnsium, n oun to surfs of CCO 3 n ly minrls in lklin lrous soils thry ruing its iovilility (Yn t l., 6; Akhtr t l., 8). Th P fiiny is lso srious thrt to sustinl proutivity in Pkistn whr mor thn 9% rl lns hv mort to svr P fiiny (FAO, 17). High lium ront ontnts, high ph n low orgni mttr oupl with low rinfll r th prinipl ftors for low P vilility in Pkistni soils. Although vrious soils worlwi nompss highr totl P rsrvs, ut th plnt vill frtion is oftn To it this ppr: Irfn, M., T. Aziz, M.A. Mqsoo, H.M. Bill, W.U.D. Khn n N. Rsh, 1x. Diffrntil prformn of lowln ri ultivrs for phosphorus uptk n utiliztion ffiiny unr hyroponi n soil onitions. Int. J. Agri. Biol. :

2 Irfn t l. / Int. J. Agri. Biol., Vol., No., 1x 1-tims lss thn th totl P ontnts (Hinsingr t l., 11). Thrfor, ky hllng to improv P ffiiny on rl nvironmnts is to ris th io-vilility of ntiv P rsrvs in soils. Consiring th intrtl soil ntur, muh ttntion hs n givn on th mthos n rts of P pplition s wll s othr st mngmnt prtis to nhn ffiiny of P ppli. Now th qustion is how plnts n ply rol in moilizing th fix or unvill soil P frtion in orr to stisfy thir mns for onomilly ptl growth. A numr of morphologil, physiologil n molulr pttions hv n volv in plnts unr P fiiny strss. Consirl vritions xist in rop spis n vn gnotyps within sm spi for thir ilitis to sustin plnt growth on soils with low P ontnts (Aziz t l., 11; Irfn t l., 17; As t l., 18). Svrl rlir stuis illustrt tht highr P ffiiny my hiv through ltr root systm rhittur (H t l., 3), rhizosphr iifition through nhn roxylt xution to moiliz/lirt P from insolul sours (Dong t l., 4), symioti ssoition with myorrhizl fungi n pplition of P soluilizing tri (Sil t l., 17), inution of high ffinity phospht trnsportrs (Yi t l., 5), ru tissu P rquirmnt for ffiint us (Hmmon t l., 4) n ttr P rmoiliztion from olr n/or non-proutiv orgns to young growing n/or proutiv orgns (Akhtr t l., 8; As t l., 18). Phosphorus ffiint ultivrs my ply n importnt rol in nhning rop proutivity in 1 st ntury, primrily us of rstrit soil rsours for ultivting rops, ostly inorgni P frtilizrs n inrsing nvironmntl onrns glolly (Fgri t l., 8; Nourgholipour t l., 17). In low-input ropping systms, pttion of P ffiint rop plnts is ruil for sustining proutivity n utilizing P sours ffiintly (Ozturk t l., 5). Intifition of P ffiint ultivrs from xisting grmplsm to mng low P soil nvironmnts is mong th vil pprohs n th most rlisti solution s gnti vritions for P ffiiny mong ultivrs of vrious rops is wll oumnt in th litrtur (Guns t l., 6; Korkmz t l., 9; Aziz t l., 11; Akhtr t l., 16; Irfn t l., 17; Nourgholipour t l., 17; As t l., 18). Mhnisms rsponsil for P ffiiny n iffr from spi to spi n vn mong plnts within sm spi (Ozturk t l., 5). Vrition in nvironmnt us for srning rop grmplsm is mong th min rsons for poor unrstning of P ffiiny mhnisms. Th informtion rgring th fft of growth mium i.., solution ultur or soil on P ffiiny mong gnotyps is xptionlly iminutiv. Aoring to Hys t l. (4), srning of wht ultivrs for P ffiiny in solution ultur is lss rlil, us ultivrs hv iffrntilly unr soil onitions. Thrfor, prsnt stuis wr onut to vlut ri ultivrs for iomss n py proution, P uptk n utiliztion ffiiny unr hyroponi n soil onitions. Mtrils n Mthos Plnt Mtril Ss of four ri ultivrs (Bsmti-, KSK-8, KSK- 434 n IR-6) us in th hyroponi n pot stuis wr otin from Ri Rsrh Institut, Kl Shh Kku Pkistn. Both stuis wr rri out unr nturl onitions of rin-prott wir hous t Institut of Soil n Environmntl Sins, Univrsity of Agriultur, Fisl Pkistn (ltitu 31º 31º 45 North; longitu 7º 5 73º Est). Hyroponi Stuy For ri nursry, ss wr surf striliz with soium hypohlorit solution (3%) follow y thorough wshing with istill wtr. Ss wr sown in polythn lin mtl trys with two inhs lyr of pr-wsh rivr sn. Two wks ol uniform slings wr shift to plsti tus hving 5 litrs of moifi Johnson s nutrint solution. Prior to sling trnsplnting, root systms of th plnts wr rfully rins with istill wtr to rmov hring sn. Th omposition of full-strngth nutrint solution (ph 5.5) ws 5. mm N, 3.5 mm K, 1.5 mm C,.5 mm Mg,.15 mm S, 5 µm Cl,.5 µm Mo, 5. µm B,.5 µm Cu,. µm Mn,. µm Zn n 5. µm F s F- EDTA. Th slings wr support y fom plugs in th hols of thrmopol sht fix t th top of plsti tus. Th slings of ri ultivrs wr rrng following two ftor ompltly rnomiz sign with six rplitions. Ri plnts wr llow to grow t two P lvls i.., fiint P ( µm Pi) n qut P ( µm Pi). Th P lvls wr mintin using potssium ihyrogn phospht (KH PO 4) s P sour. Th ph of th solution ws mintin t 5.5 ±. n ftr vry fiv ys nutrition solution ws rnw with frsh solution in orr to nsur ontinuous supply of nutrints. Plnts wr hrvst on 45 ys ftr trnsplnting, wsh with istill wtr n susquntly roots wr sprt from shoots. Aftr ir rying, plnt mtril ws ovn ri t 7 C for 48 h n stor unr sition until roring of ry wights. Pot Stuy Bulk soil (15 m surf lyr) ws ollt from rsrh r of Institut of Soil n Environmntl Sins, Univrsity of Agriultur, Fisl Pkistn. A omposit smpl of ollt soil ws ir ri n grin to pss mm siv. Aftr siving, uniform portion of soil ws nlyz for si physio-hmil hrtristis. Brifly, th soil of th xprimntl sit ws ly lom in txtur hrtriz y lklin in rtion, high in vill potssium whil low in orgni mttr, nitrogn n vill phosphorus (Tl 1). Plsti pots innr lin with polythn sht wr fill with svn kg of thoroughly mix soil.

3 Gnotypi Diffrns in Ri for PUE unr Altr Growing Mium / Int. J. Agri. Biol., Vol., No., 1x Tl 1: Slt physio-hmil hrtristis of soil us in pot xprimnt Soil hrtristis Unit Vlu Rfrn/Mtho ph s U.S. Slinity Lortory Stff (1954) EC S m -1.1 ~ Orgni Mttr %.71 Nlson n Sommrs (198) Kjlhl Nitrogn %.4 Jkson (196) Avill Phosphorus mg kg U.S. Slinity Lortory Stff (1954) Avill Potssium mg kg ~ Sturtion Prntg % 4.3 ~ Sn % 9.35 Bouyouos (196) Silt % 31. ~ Cly % ~ Txturl Clss - Cly lom ~ ph s = ph of sturt pst; EC = ltril onutivity of sturt pst xtrt Th xprimnt ws plnn following two ftor ompltly rnomiz sign with thr rpts. Th plnts wr grown t two P lvls i.., fiint P (without xtrnl P ition or only ntiv soil P i.., 5.3 mg kg -1 ) n qut P (P ition t 5 mg kg -1 soil) (Dormn n Firhurst, ). Eh pot ws lso suppli with 3 mg K O kg -1 soil long with 7 mg N kg -1 soil. Rquir quntity of P oring to trtmnts n K ws t th tim of pot filling. Howvr, N ws ppli in thr quivlnt splits. Aftr filling th pots with soil, nl wtr ws ppli from th top of th pots till soil sturtion. Th pots wr kpt for two ys to llow th soil to sttl. Ss of ri ultivrs (sm s stui in hyroponi xprimnt) wr sown in nursry trys hving similr soil. On th mrgn of 3 r lf, thr uniform n hlthy slings of h ultivr wr trnsplnt to h pot. A wtr lyr (1- m) on soil surf ws mintin uring th ntir rop prio. At mturity plnts wr hrvst, thrsh mnully to sprt py from strw. Aftr roring yil n rlt ttriuts, plnt mtril ws ovn ri t 7 C till furthr nlysis. Phosphorus Assy n Estimtion of P-ffiiny Chrtristis Ovn ri plnt mtril from oth stuis (root, shoot, py, strw) ws grin to pss through.4 mm srn using Wily s mill (IKA Wrk, Wilmington, USA) fitt with stinlss stl ls. Smpls (.3 g h) wr wt igst using 1 ml of i-i mixtur [nitri i n prhlori i (5:1, v/v)]. Th totl P onntrtion in igst smpls ws trmin following yllow olor mtho s sri y Chpmn n Prtt (1961) y ring light sorption t 47 nm wvlngth using sptrophotomtr (Shimzu UV-VIS 11, Shimzu Co. Kyoto, Jpn). Phosphorus ffiiny n rlt prmtrs wr stimt to fin rltionship twn P supply n growth prformn of ri ultivrs suh s P uptk (Zhng t l., 7), P strss ftor (Hunt, 1978), root ffiiny rtio (Jons t l., 1989) n P utiliztion ffiiny (Hmmon t l., 9). Phosphorus uptk (PU) PU(mg plnt 1 ) = P onntrtion (mg g 1 ) Root or shoot ry mttr(g plnt 1 ) PU (mg pot 1 ) = P onntrtion (mg g 1 ) Py or strw yil (g pot 1 ) Phosphorus strss ftor (PSF) PSF (%) = Dry mttr qut P Dry mttr fiint P Dry mttr qut P 1 Root ffiiny rtio (RER) RER (mg P in shoot g 1 RDM) = Shoot P uptk (mg plnt 1 ) RDM (g plnt 1 ) Whr RDM is root ry mttr Phosphorus utiliztion ffiiny (PUtE) PUtE (g SDM g 1 P) = SDM qut P SDM fiint P 1 SPU qut P SPU fiint P PUtE (g PY g 1 P) = PY qut P PY fiint P 1 PPU qut P PPU fiint P Whr SDM is shoot ry mttr (g plnt -1 ), SPU is shoot P uptk (mg plnt -1 ), PY is py yil (g pot -1 ) n PPU is py P uptk (mg pot -1 ). Sttistil Anlysis Th ollt t rgring plnt growth, iomss proution, P uptk n ffiiny rlt hrtristis of ri ultivrs unr qut n fiint P supply ws sttistilly nlyz mploying omputr softwr STATISTIX 8.1 (Anlytil Softwr, In., Tllhss, FL, USA) following th mthos of Stl t l. (1997). A two ftor ompltly rnomiz sign ws us for nlysis of vrin. Grphil prsnttion of t n orrltion offiints mong vrious prmtrs ws rri out using Mirosoft Exl (Rmon, WA, USA). Signifint iffrns mong trtmnt mns wr sprt using lst signifint iffrn tst t P.5 n prsnt with stnr rrors. Rsults Hyroponi Stuy Th tst lowln ri ultivrs vri signifintly (P.5) for root pth, root ry mttr (RDM), shoot ry mttr (SDM) n root-shoot rtio (RSR) unr qut n fiint P supply in solution ultur (Tl n Fig. 1). Th vrg root pth n RDM ws ror rltivly highr in ll ultivrs unr P fiiny thn with qut P nutrition. Root pth rng from 33. m (KSK-434) to 36. m (IR-6) unr P fiiny.

4 Irfn t l. / Int. J. Agri. Biol., Vol., No., 1x Tl : Anlysis of vrin for th omin fft of phosphorus lvls n ri ultivrs on vrious prmtrs of ri plnts grown unr hyroponi onitions Sour of vrition DF RD RDM SDM RSR RPU SPU TPU RER Phosphorus lvls (P) **.79* 194.1**.78** 343.1** ** ** 163.5** Cultivrs (C) ns 15.94** 46.9**.4* 31.4** 9.7** 368.** 93.9** P C ns.84 ns 3.1 ns. ns 8.1 ns 138.3* 133.* 56.8* Error Totl 47 DF = gr of from; RD = root pth; RDM = root ry mttr; SDM = shoot ry mttr; RSR = root-shoot rtio; RPU = root P uptk; SPU = shoot P uptk; TPU = totl (root + shoot) P uptk; RER = root ffiiny rtio ** = signifint t P.1; * = signifint t P.5; ns = non-signifint t P.5 Root pth (m) () Root ry mttr (g plnt -1 ) (). 18 ().9.8 () Shoot ry mttr (g plnt -1 ) Bsmti- KSK-8 KSK-434 IR-6 Root-shoot rtio Bsmti- KSK-8 KSK-434 IR-6 Fig. 1: () Root pth, () root ry mttr, () shoot ry mttr n () root-shoot rtio of ri ultivrs grown hyroponilly unr qut (rk rs) n fiint (gry rs) P lvls. Vlus r mns of six rplits. Brs not shring intil lttr(s) r signifintly iffrnt from h othr t two P lvls (LSD tst, P.5) Avrg ovr ll ultivrs, RDM ws nhn from 3.4 g plnt -1 t qut P to 3.5 g plnt -1 unr P fiint supply. Ri ultivr Bsmti- prou highr RDM (5.58 vs g plnt -1 ) unr P fiiny n qut P supply, rsptivly. Shoot DM vri from 5.5 to 9.8 g plnt -1, with mn vlu of 6.5 g plnt -1 in rspons to P fiiny n 8.46 to g plnt -1, with mn vlu of 1.54 g plnt - 1 t suffiint P lvl. Cultivrs lso iffr onsirly for RSR in oth P trtmnts. Th RSR ws nhn in P fiint plnts ompr with thos hving qut P supply n rng from.45 in IR-6 to.63 in Bsmti-. Phosphorus lvls n ri ultivrs h lso signifint (P.5) min n intrtiv ffts for root n shoot P uptk whn grown in solution ultur (Tl n Fig. ). Low P rsult in invril lin in P uptk y th tst ultivrs. Howvr, th xtnt of rution ws omprtivly lowr in roots thn ovgroun plnt prts. Avrg ovr ultivrs, root n shoot P uptk ws out n 3 fol lowr unr P fiiny, rsptivly thn plnts hving qut P supply. Root P uptk in plnts unr P fiiny vri from 3.79 mg plnt -1 in IR-6 to 5.78 mg plnt -1 in Bsmti-. Shoot P uptk rng from to mg plnt -1, with mn vlu of mg plnt - 1 t qut P supply n 14.8 to 1.59 mg plnt -1, with vrg of mg pln -1 unr P fiiny. Th root ffiiny rtio (RER) of tst ri ultivrs ws onsirly influn y P trtmnts n inrs lmost 3 fol unr qut P thn with P fiiny (Tl ). Th RER rng from 3.91 to 6.45 n 1.47 to 1.37 mg P g -1 RDM unr fiint n qut P, rsptivly. Ri ultivrs lso iffr signifintly for P utiliztion ffiiny (PUtE) in solution ultur. Th mximum vlu of PUtE (17. g SDM g -1 P) ws not in Bsmti- whil minimum (18.8 g SDM g -1 P) ws osrv in KSK-8, with vrg vlu of g SDM g -1 P mong th tst ultivrs (Fig. 4).

5 Gnotypi Diffrns in Ri for PUE unr Altr Growing Mium / Int. J. Agri. Biol., Vol., No., 1x Tl 3: Anlysis of vrin for th omin fft of phosphorus lvls n ri ultivrs on vrious prmtrs of ri plnts grown unr soil onitions Sour of vrition DF PL PY STY PPU STPU TPU Phosphorus lvls (P) ** 318.8** 5.71** ** ** ** Cultivrs (C) ns 66.77** 9.7** 718.7** 161.** ** P C ns 3.97 ns 1.96 ns 179.6** 64.1** 36. ns Error Totl 3 DF = gr of from; PL = pnil lngth; PY = py yil; STY = strw yil; PPU = py P uptk; STPU = strw P uptk; TPU = totl (py + strw) P uptk ** = signifint t P.1; ns = non-signifint t P.5 Root P uptk (mg plnt -1 ) () Shoot P uptk (mg plnt -1 ) () Totl P uptk (mg plnt -1 ) () Root ffiiny rtio (mg P g -1 RDM) () Bsmti- KSK-8 KSK-434 IR-6 Bsmti- KSK-8 KSK-434 IR-6 Fig. : () Root P uptk, () shoot P uptk, () totl P uptk n () root ffiiny rtio of ri ultivrs grown hyroponilly unr qut (rk rs) n fiint (gry rs) P lvls. Vlus r mns of six rplits. Brs not shring intil lttr(s) r signifintly iffrnt from h othr t two P lvls (LSD tst, P.5) Pot Stuy Ri ultivrs n P lvls h signifint ffts on pnil lngth, py yil n strw yil whn grown in soil onitions (Tl 3 n Fig. 3). Mximum pnil lngth unr P fiiny ws osrv in Bsmti- (1. m) whil minimum ws osrv in IR-6 (1. m). At qut P, Bsmti- lso prou highr pnil lngth of 15.7 m n KSK-8 prou minimum pnil lngth (13.3 m). Phosphorus fiiny strss in soil xhiit vril ffts on py n strw yil. Avrg ovr ll ultivrs, py yil ws ru lmost 1.6 fol in rspons to P fiiny ompr to plnts with qut P nutrition (1.1 vs g pot -1 ). Th highst py yil ws ror in ultivr Bsmti- (17. vs. 3.3 g pot -1 ) unr fiint n qut P supply, rsptivly. Cultivr IR-6 prou minimum py yil (9. g pot -1 ) with P fiiny whil KSK-434 show minimum py yil (16. g pot -1 ) with qut P supply. Bsmti- prou highst strw yil (33.6 vs. 4. g pot -1 ) whil KSK-8 prou minimum strw yil (4.4 vs g pot -1 ) with n without P fiiny. Py, strw n totl (py + strw) P uptk y ri ultivrs grown unr fiint n qut P nutrition is pit in Fig. 3. Signifint ffts of ultivrs, P lvls n C P intrtions wr osrv on P uptk y py n strw (Tl 3). As xpt, vrg P uptk y oth strw n py ws out two-fol highr in plnts whn P supply ws inrs from fiint to qut lvls. Mximum P uptk in py ws stimt in Bsmti- unr oth qut (15.68 mg pot -1 ) n fiint P (7.15 mg pot -1 ) lvls. Th vlus of strw P uptk rng from to 38.3 mg pot -1, with mn vlu of 35.1 mg pot -1 t fiint P lvl, whil 71.4 to 9.83 mg pot -1, with vrg vlu of mg pot -1 t qut P lvl mong th tst ultivrs. Similrly, totl P uptk vri from mg pot -1 n mg pot -1 whn P lvl ws hng from low P to high P in soil.

6 Irfn t l. / Int. J. Agri. Biol., Vol., No., 1x Pnil lngth (m) () Py yil (g pot -1 ) () Strw yil (g pot -1 ) () Py P uptk (mg pot -1 ) () f f Strw P uptk (mg pot -1 ) () Totl P uptk (mg pot -1 ) (f) f f Bsmti- KSK-8 KSK-434 IR-6 Bsmti- KSK-8 KSK-434 IR-6 Fig. 3: () Pnil lngth, () py yil, () strw yil, () py P uptk, () strw P uptk n (f) totl P uptk of ri ultivrs grown in soil unr qut (rk rs) n fiint (gry rs) P lvls. Vlus r mns of thr rplits. Brs not shring intil lttr(s) r signifintly iffrnt from h othr t two P lvls (LSD tst, P.5) Cultivrs prform iffrntilly for P utiliztion ffiiny (PUtE) rgring py proution t two P supplis in soil (Fig. 4). Mximum PUtE ws lult in KSK-8 (193.3 g PY g -1 P) follow y Bsmti- (173.6 g PY g -1 P), IR- 6 (14.8 g PY g -1 P) n KSK-434 (115. g PY g -1 P). Phosphorus Strss Ftor (PSF) Th t rgring PSF for SDM n py yil is pit in Fig. 5. Th tst ri ultivrs iffr sustntilly for PSF for SDM in solution ultur with vrg vlu of 38.4 prnt. Mximum vlu of PSF ws not in KSK-8 (47.7%) whil minimum ws osrv in KSK-434 (31.1%), with mn vlu of 38.4%. Ri ultivrs lso prform iffrntilly with rspt to PSF for py yil in soil onitions n it rng twn 6.% in Bsmti- to 49.% in IR-6, with vrg vlu of 38.1%. Disussion Th rsults of prsnt stuis show tht wi vritions xist in lowln ri ultivrs in rltion to th ffiiny with whih thy quir P from fiint mium, s wll s thir rspons to P pplition. Th gnti iffrns for P ffiiny hrtristis in ri rop hv lso n rport in rlir invstigtions (Aziz t l., 5; Fgri, 14; Vnmm t l., 15). Phosphorus uptk in shoot n py of tst ultivrs ws highr unr qut P ompr with low P whih ssoit with nhn SDM or py yil. Aoring to Bligr t l. (1998), mor P uptk in plnts growing t high P ompr with thos t low P supply is u to grtr root fin hirs nsity rsulting in ttr ility for P uptk. It ws lso ovious from th rsults tht high yiling ultivr Bsmti- h mximum P uptk in py n low yiling ultivr IR-6 h lowst py P uptk unr P fiiny. This ft ws furthr support y th positiv n signifint (P.1) orrltion twn py yil n P uptk t low (r =.97) n high P (r =.78) (Tl 4). Fgri (14) lso rport th signifint inrs in P uptk in shoot n grins of ri gnotyps t high P lvl.

7 Gnotypi Diffrns in Ri for PUE unr Altr Growing Mium / Int. J. Agri. Biol., Vol., No., 1x Tl 4: Corrltions (r) for vrious prmtrs of ri ultivrs with shoot ry mttr (hyroponi stuy) n py yil (pot stuy) t qut n fiint P lvls Prmtr Aqut P Dfiint P Shoot ry mttr (g plnt -1 ) Root pth (m).1 ns. ns Root ry mttr (g plnt -1 ).47 *.7 ** Root: shoot rtio -.6 ns -. ns Root P uptk (mg plnt -1 ).34 ns.44 * Shoot P uptk (mg plnt -1 ).78 ***.9 *** Root ffiiny rtio (mg.4 ns -.5 ns P in shoot g -1 RDM) Py yil (g pot -1 ) Pnil lngth (m).11 ns.5 * Strw yil (g pot -1 ).6 *.57 * Biologil yil (g pot -1 ).87 ***.88 *** Py P uptk (mg pot -1 ).78 **.97 *** Strw P uptk (mg pot -1 ).76 **.47 ns Totl P uptk (mg pot -1 ).83 ***.94 *** *** = signifint t P.1; ** = signifint t P.1; * = signifint t P.5; ns = non-signifint t P.5 PUtE (g DM g -1 P) Shoot ry mttr Py yil Bsmti- KSK-8 KSK-434 IR-6 Fig. 4: Phosphorus utiliztion ffiiny (PUtE) s on shoot ry mttr (hyroponi stuy) n py yil (pot stuy) of ri ultivrs lult t two P supplis. Vlus r mns of six (shoot ry mttr) n thr (py yil) rplits. Brs not shring intil lttr(s) r signifintly iffrnt from h othr (LSD tst, P.5) Unr P fiiny, photosynthts trnsporttion form shoots towrs roots inrss thry nhning root-shoot rtio (RSR) of th plnts (Mrshnr, 1995). Highr RSR t low P is wll rport us roots h to xplor lrgr volum of soil in orr to sor mor P (Aziz t l., 5; Lmrs t l., 1). In prsnt stuy, RSR ws inrs unr P fiiny n not omprtivly highr in P ffiint ultivrs thn in-ffiint ultivrs (Fig. 1) whih might on of th promising mhnisms to inrs P uptk in plnts with mor root ry mttr (RDM). Morovr, signifint orrltion (P.1) of RDM with SDM (r =.7) n shoot P uptk (r =.68) suggst th mjor rol of low groun plnt prts in P quisition unr P fiiny. Th highr P uptk is on of th rsponsil mhnisms for P ffiiny whih promots th vlopmnt of lrgr root systms thry improving plnt ss to soil P (Nourgholipour t l., 17). Cultivrs prform iffrntilly for PUtE in rltion to low P unr hyroponi n soil onitions. Phosphorus strss ftor (%) Shoot ry mttr Py yil Bsmti- KSK-8 KSK-434 IR-6 Fig. 5: Phosphorus strss ftor (prnt rution in iomss u to P fiiny) for shoot ry mttr (hyroponi stuy) n py yil (pot stuy) of ri ultivrs grown unr qut n fiint P lvls. Vlus r mns of six (shoot ry mttr) n thr (py yil) rplits. Brs not shring intil lttr(s) r signifintly iffrnt from h othr (LSD tst, P.5) Shoot ry mttr (g plnt -1 ) Py yil (g pot -1 ) y =.665x R² =.761 Aqut P Fig. 6: Rltionship of P utiliztion ffiiny with () shoot ry mttr in hyroponi n () py yil in soil onitions unr qut n fiint P lvls. Eh plott point rprsnts th iniviul vlu of smpls tkn from rplit trtmnts Th PUtE s on SDM proution rng from 18.8 to 17. g SDM g -1 P in hyroponi whil PUtE s on py yil vri from 115. to g PY g -1 P in pot stuy. Dfiint P y =.481x R² = () () y =.85x R² =.815 P utiliztion ffiiny (g SDM g -1 P) Aqut P Dfiint P y =.1x R² = P utiliztion ffiiny (g PY g -1 P)

8 Irfn t l. / Int. J. Agri. Biol., Vol., No., 1x Th xtnsiv vrition in P ffiiny mong ri gnotyps hv lso n init y Aziz t l. (5) n Fgri (14). Th PUtE show 7% vriility in SDM proution n 64% vriility in py yil unr P fiiny (Fig. 6). Th vrition in PUtE of ri ultivrs my ssoit with thir iffrntil P uptk ility n root ffiiny rtio (RER). Th RER is th inition of P uptk y shoot pr unit of root DM whih xplins th potntil of gnotyp to quir P from rooting nvironmnt. Ysn n Mlhi (9) hv rport positiv orrltion of SDM with RER n suggst tht RER n us for slting gnotyps for mor DM proution n nhn P us ffiiny. A positiv n signifint orrltion (P.1) of SDM proution with root iomss (r =.7), root P uptk (r =.44) n shoot P uptk (r =.9) in tst ri ultivrs illustrt tht ths wr th min trits rsponsil for mximizing SDM unr P fiiny. Fgri t l. (4) rport th improvmnt in SDM of ri gnotyps with th ition of P n foun signifint rltionship with grin yil. Biomss proution is influn y nvironmntl ftors. A gnotyp prouing mor ry mttr in ontroll onitions my not prou highr grin yil in fil onitions us of th ltr growing mium (Hyshi, 1995). In urrnt stuis, th highst rspons to P ition ws osrv in ultivr KSK-8 unr hyroponi n in IR-6 unr soil onitions s init y thir highr strss ftors (i.. 48 n 49%). Prnt rution in ry mttr or py proution u to P fiiny in th rooting mium n sri y th P strss ftor. It filitts to mrk lin twn P rsponsiv n non-rsponsiv ultivrs n lso xplin omprtiv ility of ultivr to prou iomss with P ition (Aziz t l., 11; Irfn t l., 17; As t l., 18). Ri ultivrs xhiit wi ivrsity for PUtE s on SDM n py yil. Th pttrns of PUtE n P fiiny tolrn mong ri ultivrs wr not sm whn grown unr hyroponi n soil onitions. Th rsults suggst tht rooting nvironmnt influn grtly on P ffiiny trits in ri plnts. Thus, prtiulr ttntion must pi to growth onitions whil srning grmplsm for P ffiiny. Conlusion Th lowln ri ultivrs xhiit wi ivrsity for P uptk n utiliztion ffiiny unr ltr growing nvironmnt. Phosphorus fiiny signifintly ru iomss proution n P uptk in ll ri ultivrs. A signifint intrtion twn ultivrs n P supply ws foun for most of th prmtrs stui s som ultivrs wr rsponsiv to P pplition whil othrs wr not. Th ultivr Bsmti- onurrntly hving highr P uptk, utiliztion ffiiny n py yil supports th i tht xploiting nturl vritions twn rop plnts inst of spifi gn mnipultion is th most prfrr tool for slting plnts for mor P uptk unr P fiiny. Th ffiint n rsponsiv ultivrs (i.. Bsmti-) n th potntil ultivrs for growing on soils with vrying P ontnts. Morovr, highr RSR, PUtE n lowr PSF wr th importnt prmtrs rsponsil for nhn P ffiiny in ffiint ultivrs whih n xploit to intify/slt ultivrs for mor iomss proution n P ffiiny. Rfrns As, M., M. Irfn, J.A. Shh n M.Y. Mmon, 18. Intr-spifi vritions mong wht gnotyps for phosphorus us ffiiny. Asin J. Agri. Biol., 6: As, M., J.A. Shh, M. Irfn n M.Y. Mmon, 18. Rmoiliztion n utiliztion of phosphorus in wht ultivrs unr inu phosphorus fiiny. J. Plnt Nutr., 41: Akhtr, M.S., Y. Oki n T. Ahi, 8. Gnti vriility in phosphorus quisition n utiliztion ffiiny from springly solul P-sours y Brssi ultivrs unr P-strss nvironmnt. J. Agron. Crop Si., 194: Akhtr, M.S., Y. Oki, Y. Nkshim, T. Ahi n M. Nishigki, 16. Phosphorus strss-inu iffrntil growth, n phosphorus quisition n us ffiiny y spring wht ultivrs. Commun. Soil Si. Plnt Anl., oi:1.18/ Aziz, T., I. Ahm, M. Frooq, M.A. Mqsoo n M. Sir, 11. Vrition in phosphorus ffiiny mong rssi ultivrs I: Intrnl utiliztion n phosphorus rmoiliztion. J. Plnt Nutr., 34: 6 17 Aziz, T., Rhmtullh, M.A. Mqsoo n T. Mnsoor, 5. Diffrns in phosphorus sorption, trnsport n utiliztion y twnty ri (Oryz stiv L.) ultivrs. Pk. J. Agri. Si., 4: 8 15 Bligr, V.C., N.K. Fgri n M. Elrshii, Toxiity n nutrint onstrints on root growth. Horti. Si., 33: Brtrn, R.E., R. Hollowy, R. Armstrong n M. MLughlin, 3. Chmil hrtristis of phosphorus in lklin soils from southrn Austrli. Aust. J. Soil Rs., 41: Bouyouos, G.J., 196. Hyromtr mtho improv for mking prtil siz nlysis of soils. Agron. J., 54: Chpmn, H.D. n P.F. Prtt, Ammonium vnt-molyt mtho for trmintion of phosphorus. In: Mthos of Anlysis for Soils, Plnts n Wtrs, pp: Univrsity of Cliforni, Division of Agriulturl Sin, Brkly, CA. USA Dhillon, J., G. Torrs, E. Drivr, B. Figuiro n W.R. Run, 17. Worl phosphorus us ffiiny in rl rops. Agron. J., 19: Dormn, A. n T. Firhurst,. Ri: Nutrint Disorrs n Nutrint Mngmnt, 1 st ition, pp: IRRI & PPI & PPIC, Mkti City & Singpor Dong, D., X. Png n X. Yn, 4. Orgni i xution inu y phosphorous fiiny n/or luminum toxiity in two ontrsting soyn gnotyps. Physiol. Plnt., 1: Fgri, N.K., 14. Yil n yil omponnts n phosphorus us ffiiny of lowln ri gnotyps. J. Plnt Nutr., 37: Fgri, N.K., E.M. Cstro n V.C. Bligr, 4. Rspons of upln ri gnotyps to soil iity. In: Th R Soils of Chin: Thir Ntur, Mngmnt n Utiliztion, pp: Wilson, M.J., Z. H n X. Yng (s.). Dorrht, th Nthrlns, Kluwr Ami Pulishrs Fgri, N.K., V.C. Bligr n Y.C. Li, 8. 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9 Gnotypi Diffrns in Ri for PUE unr Altr Growing Mium / Int. J. Agri. Biol., Vol., No., 1x Guns, A., A. Inl, M. Alpsln n I. Ckmk, 6. Gnotypi vrition in phosphorus ffiiny twn wht ultivrs grown unr grnhous n fil onitions. Soil Si. Plnt Nutr., 5: Hmmon, J.P., M.R. Broly n P.J. Whit, 4. Gnti rsponss to phosphorus fiiny. Ann. Bot., 94: Hmmon, J.P., M.R. Broly, P.J. Whit, G.J. King, H.C. Bown, R. Hyn, M.C. Mhm, A. M, T. Ovrs, W.P. Sprkln n D.J. Grnwoo, 9. Shoot yil rivs phosphorus us ffiiny in Brssi olr n orrlts with root rhittur trits. J. Exp. Bot., 6: Hyshi, H., Trnslotion, storg n prtitioning of photosynthti prouts. In: Sin of th Ri Plnt: Physiology, pp: Mtsuo, T., K. Kumzw, R. Ishii, K. Ishihr n H. Hirt (s.). Tokyo: Foo n Agriultur Poliy Rsrh Cntr Hys, J.E., Y.G. Zhu, T. Mimur n R.J. Ri, 4: An ssssmnt of th usfulnss of solution ultur in srning for phosphorus ffiiny in wht. Plnt Soil, 61: H, Y., H. Lio n X.L. Yn, 3. Loliz supply of phosphorus inus root morphologil n rhitturl hngs of ri in split n strtifi soil ulturs. Plnt Soil, 48: Hinsingr, P., E. Btnourt, L. Brnr, A. Brumn, C. Plssr, J. Shn, X. Tng n F. Zhng, 11. P for two, shring sr rsour: Soil phosphorus quisition in th rhizosphr of intrropp spis. Plnt Physiol., 156: Hunt, R., Plnt Growth Anlysis. Ewrs Arnol Pul. Lt., Lonon Irfn, M., J.A. Shh n M. As, 17. Evluting th prformn of mungn gnotyps for grin yil, phosphorus umultion n utiliztion ffiiny. J. Plnt Nutr., 4: 79 7 Irfn, M., M. As, J.A. Shh n M.Y. Mmon, 18. Grin yil, nutrint umultion n frtilizr ffiiny in r wht unr vril nitrogn n phosphorus rgims. J. Bsi Appl. Si., 14: 8 86 Irfn, M., M.Y. Mmon, J.A. Shh n M. As, 16. Applition of nitrogn n phosphorus in iffrnt rtios to fft py yil, nutrint uptk n ffiiny rltions in ri (Oryz stiv L.). J. Environ. Agri., 1: Jkson, M.L., 196. Soil Chmil Anlysis, pp: Englwoo liffs, NJ: Printi Hll, In Jons, G.P.D., G.J. Blir n R.S. Jssop, Phosphorus ffiiny in wht - A usful sltion ritrion. Fil Crops Rs., 1: Korkmz, K., H. Iriki, E. Krnz, G. Buyuk, J. Ryn, A.C. Ulgr n H. Oguz, 9. Phosphorus us ffiiny of wht gnotyps grown in lrous soils. J. Plnt Nutr., 3: Lmrs, H., M.C. Brunrtt, J.A. Rvn n S.D. Hoppr, 1. Plnt minrl nutrition in nint lnsps: High plnt spis ivrsity on infrtil soils is link to funtionl ivrsity for nutritionl strtgis. Plnt Soil, 334: Mrshnr, H., Minrl Nutrition of Highr Plnts. Sn Digo, CA: Ami Prss Nlson, D.W. n L.E. Sommrs, 198. Totl ron, orgni ron n orgni mttr. In: Mthos of Soil Anlysis, Agronomy, No. Prt : Chmil n Miroiologil Proprtis, n ition, pp: Pg, A.L., R.H. Millr n D.R. Kny (s.). Amrin Soity of Agronomy, Mison, Wisonsin, USA Nourgholipour, F., H.M. Hossini, M.M. Thrni, B. Motshrzh n F. Moshiri, 17. Comprison of phosphorus ffiiny mong spring oils rp ultivrs in rspons to phosphorus fiiny. N.Z. J. Crop Horti. Si., oi:1.18/ Ozturk, L., S. Ekr, B. Torun n I. Ckmk, 5. Vrition in phosphorus ffiiny mong 73 r n urum wht gnotyps grown in phosphorus-fiint lrous soil. Plnt Soil, 69: 69 8 Sil, N.A., S.A. Aro, M. As, M. Irfn n M.Y. Mmon, 17. Stuis on iffrnt lvls of phosphorus frtilizr n phosphorus soluilizing tri in mungn (Vign rit L.). Pk. J. Biothnol., 14: Stl, R.G.D., J.H. Torri n D.A. Diky, Prinipls n Prours of Sttistis-A Biomtril Approh, pp: 4 7. MGrw-Hill Book Intr. Co., Singpor Stwrt, W.M., D.W. Di, A.E. Johnston n T.J. Smyth, 5. Th ontriution of ommril frtilizr nutrints to foo proution. Agron. J., 97: 1 6 U.S. Slinity Lortory Stff, Dignosis n Improvmnt of Slin n Alkli Soils. USDA Hnook No. 6. Wshington DC, USA Vn, C.P., C. Uh Ston n D.L. Alln, 3. Phosphorus quisition n us: ritil pttions y plnts for suring nonrnwl rsour. Nw Phytol., 157: Vnmm, E., T. Ros, K. Sito, K. Jong n M. Wissuw, 15. Intgrtion of P quisition ffiiny, P utiliztion ffiiny n low grin P onntrtions into P-ffiint ri gnotyps for spifi trgt nvironmnts. Nutr. Cyl. Agroosyst., oi:1.17/s Yn, X., P. Wu, H. Ling, G. Xu, F. Xu n Q. Zhng, 6. Plnt nutriomis in Chin: An ovrviw. Ann. Bot., 98: Ysn, M. n S.S. Mlhi, 9. Vrition in yil, phosphorus uptk, n physiologil ffiiny of wht gnotyps t qut n strss phosphorus lvls in soil. Commun. Soil Si. Plnt Anl., 4: Yi, K., Z. Wu, J. Zhou, L. Du, L. Guo, Y. Wu n P. Wu, 5. OsPTF1, novl trnsription ftor involv in tolrn to phospht strvtion in ri. Plnt Physiol., 138: Zhng, Z., X. Tin, L. Dun, B. Wng, Z. H n Z. Li, 7. Diffrntil rsponss of onvntionl n t-trnsgni otton to potssium fiiny. J. Plnt Nutr., 3: (Riv 4 July 18; Apt 9 Otor 18)