THE ROLE OF POTASSIUM IN ALLEVIATING BORON TOXICITY AND COMBINED EFFECTS ON NUTRIENT CONTENTS IN PEPPER

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1 64 Bulrin Journl of Ariulturl Sin, 21 (No 1) 215, 64-7 Ariulturl Amy THE ROLE OF POTASSIUM IN ALLEVIATING BORON TOXICITY AND COMBINED EFFECTS ON NUTRIENT CONTENTS IN PEPPER (Cpsium nnuum L.) H. SAMET 1*, Y. CIKILI 2 n S. DURSUN 2 1 Dprtmnt of Crop n Animl Proution, Votionl Shool of Foo n Ariultur, Koli Univrsity, Koli, Turky 2 Dprtmnt of Crop n Animl Proution, Cilimli Votionl Shool, Duz Univrsity, 8175 Duz, Turky Astrt SAMET, H., Y. CIKILI n S. DURSUN, 215. Th rol of potssium in llvitin oron toxiity n omin ffts on nutrint ontnts in pppr (Cpsium nnuum l.). Bul. J. Ari. Si., 21: 64-7 As rrs th intrtion twn oron (B) n potssium (K), thr is limit our knowl, n th ntur of this omplx intrtion is still lrly unknown. Th prsnt stuy ws s on th hypothsis tht K miht llvit th trimntl ffts of xss B. For this purpos, th ffts of thr lvls of K (, 2, n 4 m k -1 ) n four lvls of B (, 5, 1, n 2 m k -1 ) on th rowth n minrl nutrint ontnts of pppr (Cpsium nnuum L.) wr invstit in rnhous nturl liht onitions. Plnt rowth ws rmtilly rstrin y xss B, whil K prtilly ttnut th inhiitory fft of xss B on plnt rowth. Howvr, this fft ws sn mor in th shoots thn in th roots. Alon with inrsin lvls of B, itions of K rs th B ontnt of th pppr shoots. A B inrs th shoot ontnts of phosphorus (P), mnsium (M), lium (C), mnns (Mn), iron (F), oppr (Cu), n soium (N), whil K rs th shoot ontnts of P, M, C, n N. It ws onlu tht ition of K to th rowin mi n nfiil in llvitin plnt rowth rution n minrl imlns us y xss B. Ky wors: Cpsium nnuum L., oron toxiity, potssium, llvition, nutrint ontnt Introution Boron (B), n ssntil nutrint for hihr plnts, is primrily sor y roots in th form of ori i n, in onntion with th trnspirtion rt, quikly rlots to th rowin points (Brown n Shlp, 1997). Th B uptk of plnts is rlt to th B onntrtions in th soil n th wtr onsumption of th plnt (Hu n Brown, 1997). It plys vitl rol within th mtolism of nuli i, rohyrt n protin, IAA, RNA n phnol (Loomis n Durst, 1992; Tnk n Fujiwr, 28). Furthrmor, B is involv in mmrn funtion, throuh omplx formtions with lyoprotin (Golh n Wimmr, 27), n in th trnsport of sur (Stvn n Morln, 1981). Th rn twn B toxiity n B fiiny is vry nrrow, n oth us sinifint rop losss. Boron toxiity in rl lns hs n ttriut to ovr-frtiliztion with B, B-ontmint irrition wtr, surf minin, n formtion of soil on mrin simnt (Nl t l., 1997). Muh nzym tivity is fft ntivly y toxi lvl of B in plnts (Shkolnik, 1974), usin nhnmnt of mmrn prmility n rtion of mmrn intrity n mmrn strutur (Krl t l., 23). Potssium (K) is ll non-onstitutiv lmnt s it os not form omponnts/ ompouns in th plnt systm, ut ts s plnt nutrint with vitl rol in mtolism, inluin protin synthsis, plnt wtr ln mintnn (Mrshnr, 212), n trnsporttion of wtr n nutrints. Potssium is sor y th roots in th form of K + ions n xists s fr or sorptiv-oun tion tht n ispl quit sily in plnts (Linhur, 1985). Plnts n K to rult som vitl tivitis suh s nzym tivtion, photosyn- * Corrsponn to uthor: hlilsmt@yhoo.om

2 Th Rol of Potssium in Toxiity n Effts on Nutrint Contnts in Pppr (Cpsium nnuum L.) 65 thsis, osmo-rultion, stomtl movmnt, nry trnsfr, phlom trnsport, tion-nion ln n strss rsistn (Mrshnr, 212). Morovr, K ssntil funtions s trnsmittr of ltril hr in th plnt ll n tivt ovr 6 nzyms in th plnt systm s tlysts for mny of th nzymti prosss in th plnt (Mnl n Kirky, 21). Boron ffts othr nutrint lmnts s wll, spifilly K, lium (C), mnsium (M), n soium (N) (Mozfr, 1989). Du to th ovrlppin rols ply y K n B in plnt physioloy, th ffts of ths two plnt nutrints on plnt vlopmnt r sinifint. Both K n B srv s uffrs n r nssry for th mintnn of onutin tissus (Mnl n Kirky, 21). Shon t l. (199) rport tht n optiml lvl of B inrss K prmility in th ll mmrn. Prvious stuis hv invstit th rltionship twn K n toxi lvls of B. Ismil (23) mphsiz th ft tht B n K ontnts for oth miz n sorhum inrs with xss B trtmnts. Furthrmor, xss B trtmnt inrs B n K ontnts in rish (Triq n Mott, 26) n in ri (Kumr t l., 1981). Aitionlly, it ws not tht B n K onntrtion of tomto fruit inrs whn inrsin K trtmnts wr ppli to th soil tothr with folir B (Hun n Snpp, 29). Th shoot n root rowth of n (Smt t l., 213) n uumr (Çıkılı t l., 213) wr imprss y xss B, ut K to th rowth mi mitit th trimntl fft of xss B. In th prsnt stuy, th rol of K on th llvition of B toxiity ws invstit in pppr, s B-snsitiv plnt. Mtril n Mthos Growth Conitions n Trtmnts: A pot ultur xprimnt ws onut unr nturl liht in rnhous onitions in th summr of 211. Pppr (Cpsium nnuum L., v. Ylov Çorı-12 ) ss wr rmint in slin viol fill with pt. Thr- wk-ol slins wr trnsplnt, on plnt pr pot ontinin 2 k of ir-ri soil. Th proprtis of th soil us in th xprimnt wr s follows: lom txtur (sn: ly; 36: 22, y ry wiht), ph (1:2.5 soil/wtr) 7.34, sturtion xtrt of.51 S/m EC, CCO /k, orni ron 6.25 k -1 n totl nitron.86 k -1. Th onntrtions of NH 4 OA-xtrtl K, N, M, n C wr 1, 64, 124, n 2151 m k -1, rsptivly. Th NHCO 3 -vill P onntrtion ws m k -1 n hot wtr xtrtl-b ws 1.64 m k -1. Th onntrtions of DTPA-xtrtl F, Mn, Zn, n Cu wr 24.28, 65.27, 2.9, n 1.17 m k -1, rsptivly. Th soil hrtristis wr trmin orin to mthos til in P t l. (1982). Boron ws ppli s H 3 BO 3 t lvls of, 5, 1, n 2 m k -1, n potssium s K 2 SO 4 ws t lvls of, 2, n 4 m k -1. Th trtmnts wr rplit thr tims in ompltly rnomiz ftoril sin. For sl frtiliztion, N n P, s NH 4 NO 3 n NH 4 H 2 PO 4, wr ppli t 15 n 75 m k -1, rsptivly, n mix proprly for plntin out th slins. Durin th xprimntl prio, th soil ws wtr with tp wtr n kpt t pproximtly 7% of th fil pity. Chmil Anlyss: Aftr six wks, th shoots wr rfully hrvst, wsh with runnin tp wtr, n thn rins thr tims with -ioniz wtr. Similrly, th roots wr rfully rmov, ln n wsh. All shoots n roots wr ovn ri t 7 C for t lst thr ys, n th ry wiht (DW) ws immitly msur. All mtrils wr roun sprtly n kpt for B, K n th othr nutrint ion nlyss. Th smpls wr ist y usin th ry-sh mtho for xtrtion. Ths nutrint ions wr trmin y ICP-OES (Prkin Elmr Optim 21 DV). Th totl uptks in th shoots wr lult usin th followin formultion: Totl K or B uptk = DW shoot x [K or B] shoot Sttistil Anlyss: Th sin strutur ws ompltly rnomiz. Otin t wr nlyz y ANOVA n th iffrns wr ompr y th LSD tst (P <.5) n prform y usin th MINITAB pk prorm. Rsults n Disussion Plnt Growth n Dry Wihts: Th omin fft of K n B on shoot n root ry wihts n th mmrn prmility of pppr r shown in Tl 1. Th ffts of B (P <.1), K (P <.1) n thir intrtion (P <.1) on th DW in th shoots n roots wr foun to sttistilly sinifint. Th shoot ry wihts wr rmtilly rs with inrsin B pplitions. Howvr, with th pplition of 2 m k -1 K to th soil, th shoot ry wihts t ll B lvls wr foun to mor thn two tims hihr thn th ontrol. Compr to th ontrol, th vr shoot DW inrss for 2 n 4 m k -1 K to th soil wr 116.4% n 62.3%, rsptivly. Similrly, rss in root ry wihts with B lvls wr mliort y inrsin K pplitions. Aorin to th vr of th K, th roots wr influn lss from B toxiity thn th shoots. This init tht B trnsports rpily to th uppr orns n umults thr (Cmho-Cristol t l., 28). Th rution of B toxiity ffts on shoot n root rowth hs n stui in ultivt plnts suh s pppr (Yrmiyhu t l., 28), tomto n uumr (Alpsln n Guns, 21). Potssium

3 66 H. Smt, Y. Cikili n S. Dursun mliortion on shoot n root rowth of plnts unr B-toxi onitions ws lso rport prviously for uumr (Cikili t l., 213) n n (Smt t l., 213). Boron n Potssium Contnts n Uptks of Plnts: Th omin fft of K n B pplitions on th K n B ontnts of th shoot n thir uptks r ivn in Fiur 1, n th hih orrltion twn th pplitions n th ontnts is lrly visil. Th umultion of B in th lvs of th plnt pns only on th B lvls in th root mi (Slins t l., 1986). Th shoot B ontnt linrly inrs pnin on th inrsin B lvls, ut rmtilly rs with inrsin supplmnttions of K (Fiur 1). This miht xplin s prottiv fft rsultin from th ssntil rol of K in th physioloil pross, i.., th mintnn of onutin tissus or tion-nion lns. Thrfor, suppli K sm to llvit th toxi ffts of B. Th shoot K ontnt of pppr ws mrkly inrs y K pplitions, ut with B pplitions, th shoot K ontnts i not follow isrnil trn (Fiur 1). In K-untrt plnts n in th hihst K-trt (4 m k -1 K) plnts, th shoot K ontnts sinifintly rs with inrsin B pplition, ut inrs t th lvl of 2 m k -1 K. Irrsptiv of th lvl of K trtmnt, howvr, suppli B sinifintly ru th shoot K ontnt of th plnts. This fft miht hv n us y K fflux out of th roots u to th trimntl fft of B toxiity on plsmlmm prmility. Similr finins hv n rport in plnts suh s hot pppr in slin onitions (Supnjni, 26), tomto (Alvrz-Tinut t l., 1979), n miz (L, 1978). Furthrmor, Wuin t l. (1987) not tht thr ws no iffrn in th K ontnt of otton lvs with B pplition. But, thr r som vin rlt to positiv ffts of xss B on K ontnt of n (Smt t l., 213), uumr (Cikili t l., 213), tomto, pppr n uumr (Dursun t l., 21), Brussls sprouts (Turn t l., 29), Brssi rp (Triq n Mott, 26) n sunflowr (Shon t l., 199). Th ffts of K n B intrtion wr sinifint for th K uptk (P <.1), ut not sinifint for th B uptk of pppr. Th B uptk in th shoots inrs sinifintly with suppli K n B, xpt t th hihst lvl of B (Fiur 1). Crr t l. (211) init tht thr ws linr rltionship twn B pplition n uptk. Th B uptk in rish ws nhn with inrs pplitions of B, s rport y Triq n Mott (26). Th shoot uptk of K inrs xptly with itions of K, whil it rs sinifintly with itions of B (Fiur 1). Th inrmnt in th K uptk of th plnts ws rtr t low lvl of K (2 m k -1 ) thn t hih K (4 m k -1 ) lvl. This rution of rowth miht u to n ion imln risin from n xss mount of K in th rowin mium. Dvis t l. (23) stui th ffts of B in tomto n rport tht th ition of B inrs rowth n th uptk of K n B. Minrl Nutrint Contnts of Plnts: Th ontnts of phosphorus P, C, M, n N in th pppr shoots wr influn y th inrsin of oth B n K (Fiur 2). Th Tl 1 Th omin ffts of B n K on shoot n root ry wiht of pppr A K, A B, m k -1 m k Mn Shoot ry wiht, plnt ± ±.3.59 ±.9.3 ±..61 ± ± ± ±.5.12 ± ± ± ± ±.7.1 ±.3.99 ±.12 Mn 1.69 ± ± ±.9.8 ±.2 ANOVA BxK ** LSD.5 B:.188 K:.163 BxK:.326 Root ry wiht, plnt ±.1.33 ±.2.21 ±.2.18 ±.2.3 ± ± ±.5.32 ±.1.3 ±..45 ± ±.3.41 ±.5.3 ±.1.6 ±.1.31 ±.5 Mn.62 ±.8.42 ±.3.27 ±.2.9 ±.1 ANOVA BxK ** LSD.5 B:.66 K:.57 BxK:.114 Vlus r mns of thr rplits (Mn ± SE, n = 3). LSD.5 inits sinifint iffrns orin to Dunn s Multipl Rn Tst (P <.5). ANOVA shows sinifint iffrn t: P <.1 n P <.1.

4 Th Rol of Potssium in Toxiity n Effts on Nutrint Contnts in Pppr (Cpsium nnuum L.) 67 intrtion of B n K h sinifint fft on th shoot P n M ontnts (P <.1) n th shoot N ontnt (P <.1), ut not on th shoot C ontnt. Th shoot P n M ontnts with inrss of oth B n K vri from m -1 n m/, rsptivly (Fiur 2 n 2). Th shoot P n M ontnts inrs rmtilly with suppli B, ut rs with suppli K. Ths hns in shoot nutrint ontnts miht hv ourr s nutrint sorption inrs u to th trimntl fft of xss B on plsmlmm prmility. Ths rsults r with th prvious finins of Sotiropoulos t l. (26), who rport tht th P, C n M onntrtions of ppl wr inrs y inrsin B onntrtion of th ultur mium from.1 to 6 mm B. Furthrmor, Hun n Snpp (29) osrv tht oth folir-ppli B n inrsin soil K lvls nhn th K ontnt n lso slihtly inrs th tissu P, C, n M onntrtion in tomto. Morovr, Dursun t l. (21) rport tht B pplition inrs th tissu P n K onntrtion of tomto, pppr, n uumr, ut rs th tissu C n M. Th shoot C ontnt with th inrsin of oth B n K rn from m -1, rsptivly. Rrlss of h sprt lvl of pplition, th C ontnt lin with suppli K, whil it ru with suppli B (Fiur 2). As K, C, n M ompt with h othr, th ition of ny on of thm in th rowth mium will ru th uptk rt of th othr two (Mnl n Kirky 21). Tnk (1967) rport tht th uptks of C n B wr rs whn K ws inrs in rowth mi. Aitionlly, Alvrz-Tinut t l. (1979) xplin tht th uptk n trnslotion of P, K, n C ws sinifintly stimult y xss B in hyroponilly-rown tomto. Th shoot N ontnt vri from µ -1 with th inrsin of oth B n K. Althouh th N ontnt follow no isrnil pttrn, it ws rmrkly ru with K, whil B inrs th shoot N ontnt (Fiur 2). Th rutions of th N ontnt with K miht rsult from th ntonisti rltionship twn K n N, s El-Kholi (1961) osrv tht, with lvls of xss B, n ntonism xist twn N n K. Th inrmnt in P, K n N ontnts with ppli B ws not in rly (Sinh n Sinh, 1984). Morovr, lry n lttu plnts in sn ultur umult mor K with suppli B, ut lss C, M n N, s rport y Frnois (1988). () B ontnt (µ -1 ) () K ontnt (m -1 ) Kx A B (m k -1 ) f h h h Mn of 2 4 Mn of K supply A K (m k -1 ) () B uptk (µ plnt -1 ) KxB NS f f 3 A B (m k -1 ) Mn of 2 4 Mn of K supply A K (m k -1 ) Fi. 1. Th omin ffts of potssium n oron on th ontnts n uptks of B n K in pppr shoots Vlus r mns of thr rplits (Mn ±SE, n = 3) n th rs rprsnt thir stnr rrors. Diffrnt lttrs ov h olumn rprsnt sinifint iffrns s on Dunn s Multipl Rn Tst (P <.5). It inits tht smll lttrs for th omin ffts of suppli B n K, pitl lttrs for mn of, n numrs for mn of K supply r th sttistil iffrns. Sinifint iffrn is shown t: ** P <.1, *** P <.1, NS not sinifint () K uptk (m plnt -1 ) Kx 2 C B A D

5 68 H. Smt, Y. Cikili n S. Dursun () A B (m k -1 ) P ontnt (m -1 ) () C ontnt (m -1 ) 4,2 3,6 3, 2,4 1,8 1,2,6, K ** KxB NS Mn of 2 2 B B B K ** 2 4 Mn of A K (m k -1 ) K supply A () M ontnt (m -1 ) () N ontnt (µ -1 ) 5,6 4,8 4, 3,2 2,4 1,6,8, A B (m k -1 ) Mn of K ** B ** - i - j f h Mn of A K (m k -1 ) K supply Fi. 2. Th omin ffts of potssium n oron on P, C, M n N ontnts of pppr shoots Vlus r mns of thr rplits (Mn ±SE, n = 3) n th rs rprsnt thir stnr rrors. Diffrnt lttrs ov h olumn rprsnt sinifint iffrns s on Dunn s Multipl Rn Tst (P <.5). It inits tht smll lttrs for th omin ffts of suppli B n K, pitl lttrs for mn of, n numrs for mn of K supply r th sttistil iffrns. Sinifint iffrn is shown t: ** P <.1, *** P <.1, NS not sinifint () F ontnt (µ -1 ) () Mn ontnt (µ -1 ) Kx f Kx f f A B (m k -1 ) f f f f Mn of 2 4 Mn of A K (m k -1 ) K supply () Zn ontnt (µ -1 ) () Cu ontnt (µ -1 ) K NS B NS Kx K NS A B (m k -1 ) i k - Kx Mn of 2 4 Mn of A K (m k -1 ) K supply Fi. 3. Th omin ffts of potssium n oron on F, Mn, Zn, n Cu ontnts of pppr shoots Vlus r mns of thr rplits (Mn ±SE, n = 3) n th rs rprsnt thir stnr rrors. Diffrnt lttrs ov h olumn rprsnt sinifint iffrns s on Dunn s Multipl Rn Tst (P <.5). It inits tht smll lttrs for th omin ffts of suppli B n K. Sinifint iffrn is shown t: ** P <.1, *** P <.1, NS not sinifint

6 Th Rol of Potssium in Toxiity n Effts on Nutrint Contnts in Pppr (Cpsium nnuum L.) 69 Th ontnts of iron (F), mnns (Mn), zin (Zn), n oppr (Cu) in th pppr shoots wr influn y th inrsin of oth B n K (Fiur 3). Th intrtion of B n K h sinifint fft on th shoot ontnts of F, Mn, Zn (P <.1), n Cu (P <.1). Th shoot F n Cu ontnts rn from µ -1 (Fiur 3), n µ -1 (Fiur 3), rsptivly, with inrsin lvls of oth B n K. A B sinifintly nhn th F n Cu ontnts. This miht n umultiv fft u to th rution of plnt rowth rsultin from B toxiity. Inrmnts in onntrtions of F n Cu with th inrsin of B hv n osrv prviously in kiwifruit (Sotiropoulos t l., 1999) n rounnut (Ptl n Golkiy, 1986); howvr, rrlss of th lvls of suppli B, no isrnil trn ws osrv with K. Th Mn ontnt of th plnt shoots ws sinifintly nhn with inrsin lvls of oth B n K n vri from µ -1 (Fiur 3). Th shoot Zn ontnt rn from µ -1 with th inrsin of oth B n K (Fiur 3). In K-untrt plnts, th shoot Zn ontnt rs with itions of B, ut without ny notl pttrn of lin (Fiur 3). In K-trt plnts, howvr, sliht inrss wr osrv in th Zn ontnt. In rmnt with ths finins, similr rsults wr hiv y Sotiropoulos t l. (1999), who rport tht th onntrtions of Zn n Cu inrs with inrsin B in kiwifruit. Turn t l. (29) mntion inrss in th tissu F, Mn, Zn, n Cu ontnts of Brussls sprouts rsultin from B pplition. Triq n Mott (26) lso foun inrmnts in Zn n Cu onntrtions, ut rss in F n Mn onntrtions in rish. Thy lso foun tht low n hih lvls of B h intrtiv ffts on th onntrtion n totl uptk of mironutrints. Conlusion This stuy monstrt tht suppli K prtilly ttnut th inhiitory fft of xss B on plnt rowth. Howvr, this fft ws sn mor in th shoots of th plnts thn in th roots. With inrsin lvls of B, K rs th B ontnt of th shoots. A B inrs th shoot ontnts of P, M, C, Mn, F, Cu, n N, whil K rs th shoot ontnts of P, M, C, n N. Susquntly, ition of K to th rowin mi n nfiil in llvitin plnt rowth rution n minrl imlns us y xss B. Rfrns Alpsln, M. n A. Guns, 21. Intrtiv ffts of oron n slinity strss on th rowth, mmrn prmility, n minrl omposition of tomto n uumr plnts. Plnt & Soil, 236: Alvrz-Tinut, M. C., A. Ll, I. Aui n L. Rl-Mrtinz, Physioloil ffts of B-Mn intrtion in tomto plnts, II. Th uptk n trnslotion of mro lmnts. Anls Efoloi y Aroioloi, 38: Brown P. H. n B. J. Shlp, Boron moility in plnts. Plnt n Soil, 193: Cmnho-Cristol, J. J., J. Rxh n A. Gonzls-Fonts, 28. Boron in plnts: Dfiiny n toxiity. Journl of Intrtiv Plnt Bioloy, 5 (1): Crr, C.E., W. Linmnn, R. Flynn n R. Stinr, 211. Boron frtiliztion of Chil pppr unr rnhous onitions. Wstrn Nutrint Mnmnt Confrn, 9: Cikili, Y., H. Smt, n S. Dursun, 213. Effts of potssium trtmnt on llvition of oron toxiity in uumr plnt (Cuumis stivus L.). Soil-Wtr Journl, 2(2-1): Dvis, J. M., D. C. Snrs, P. V. Nlson, L. Lnnik n W. J. Sprry, 23. Boron improvs rowth, yil, qulity, n nutrint ontnt of tomto. Journl of th Amrin Soity for Hortiulturl Sin, 128: Dursun, A., M. Turn, M. Ekini, A. Guns, N. Atolu, A. Esrinu n E.Yilirim, 21. Effts of oron frtilizr on tomto, pppr, n uumr yils n hmil omposition. Communitions in Soil Sin n Plnt Anlysis, 41: El-Kholi, A. F., An xprimntl stuy of th influn of th mirolmnts on th uptk of mrolmnts y plnts. Soils & Frtilizr, 24: Frnois, L. E., Yil n qulity rsponss of lry n risp h lttu to xss oron. Journl of th Amrin Soity for Hortiulturl Sin, 113: Golh, H. E. n M. Wimmr, 27. Boron in plnts n nimls: Is thr rol yon ll-wll strutur? Journl of Plnt Nutrition & Soil Sin, 17: Hu, H. n P. H. Brown, Asorption of oron y plnt roots. Plnt & Soil, 193: Hun, J. n S.S. Snpp, 29. Potssium n oron nutrition nhn fruit qulity in Miwst frsh mrkt tomtos. Communitions in Soil Sin & Plnt Anlysis, 4: Ismil, A. M., 23. Rspons of miz n sorhum to xss oron n slinity. Bioloi Plntrum, 47 (2): Krl, E., M. Yul n H. A. Oktm, 23. Antioxint rsponss of tolrnt n snsitiv rly ultivrs to oron toxiity. Plnt Sin, 164: Kumr, S., B. R. Aror n H. S. Hunl, Potssium-oron synrism in th nutrition of ri (Oryz stiv L.). Journl of th Inin Soity of Soil Sin, 29: L, D. R., Effts of oron on th physioloil tivity of zin in miz. Austrlin Journl of Ariulturl Rsrh, 29: Linhur, M. G., Th rol of potssium in th plnt with mphsis on strss onitions (wtr, tmprtur, slinity). In: Proins of th Potssium Symposium. Dprtmnt of Ariultur n Wtr Supply, Intrntionl Potsh Institut n Frtility Soity of South Afri. Prtori, Otor p

7 7 Loomis, W.D. n R. W. Durst, Chmistry n ioloy of oron. Bioftors, 3: Mrshnr, H., 212. Mrshnr s Minrl Nutrition of Hihr Plnts. 3 r ition. Ami Prss, Lonon. pp Mnl, K. n E. A. Kirky, 21. Prinipls of Plnt Nutrition, 5 th ition. Dorrth: Kluwr Ami Pulishrs. 849 pp. Mozfr, A., Boron fft on minrl nutrition of miz. Aronomy Journl, 81: Nl, R.O., G. S. Bnulos n J. G. Pull, Boron toxiity. Plnt & Soil, 193: P, A., R. Millr n D. Kny, Mthos of soil nlysis. Amrin Soity of Aronomy, In., Mison WI, USA. Ptl, M. S. n B. A. Golkiy, Efft of lium ront n oron pplition on yil n nutrint uptk y rounnut. Journl of th Inin Soity of Soil Sin, 84: Slins, R., A. Cr n V. Mrtinz, Th intrtiv ffts of oron n mronutrints (P, K, C n M) on po yil n hmil omposition of p (Pisum stivum L.). Journl of Hortiulturl Sin & Biothnoloy, 61: Smt, H., Y. Cikili, n S. Dursun, 213. Intrtiv ffts of oron n potssium on th rowth n minrl omposition of n (Phsolus vulris L.). Soil-Wtr Journl, 2(2-1): Shon, M.K., A. Novky n D. G. Blvins, 199. Boron inus hyprpolriztion of sunflowr root ll mmrns n inrss mmrn prmility to K +1. Plnt Physioloy, 93: Shkolnik, M.Y., Gnrl onption of physioloil rol of oron in plnts. Plnt Physioloy, 21: Sinh, V. n S. P. Sinh, Efft of ppli oron on nutrints n uptk y rly rop. Currnt Ariultur, 8: Sotiropoulos, T. E., A. Molssiotis, D. Almliotis, G. Mouhtriou, K. Dimssi, I. Thrios n G. Dimntiis, 26. Growth, nutritionl sttus, hlorophyll ontnt, n ntioxint H. Smt, Y. Cikili n S. Dursun rsponss of th ppl rootstok MM 111 shoots ultur unr hih oron onntrtions in vitro. Journl of Plnt Nutrition, 29 (3): Sotiropoulos, T. E., N. Ionnis, K. Thrios n N. Dimssi, Clium pplition s mns to improv tolrn of kiwifruit (Atinii liios L.) to oron toxiity. Sinti Hotiultur, 81 (4): Stvn, C. H. n D. E. Morln, Co-trnsport of Potssium n Sur ross th Plsmlmm of Msophyll Protoplsts. Plnt Physioloy, 67: Supnjni, K. D. L., 26. Hot pppr rspons to intrtiv ffts of slinity n oron. Plnt, Soil & Environmnt, 52 (5): Tnk, H., Boron sorption y rop plnts s fft y othr nutrints of th mium. Soil Sin & Plnt Nutrition, 13 (2): Tnk, M. n T. Fujiwr, 28. Physioloil rols n trnsport mhnisms of oron: Prsptivs from plnts. Pflurs Arhiv - Europn Journl of Physioloy, 456: Triq, M. n C. J. B. Mott, 26. Efft of ppli oron on th umultion of tions n thir rtios to oron in rish (Rphnus stivus L.). Soil & Environmnt, 25 (1): Turn, M., A. Dursun, N. Atolu, A. Guns, M. Ekini, T. Ozts, Q. M. Kttrins n Y. M. Hun, 29. Yil n hmil omposition of Brussls sprout (Brssi olr L. mmifr) s fft y oron mnmnt. Hortiulturl Sin, 44 (1): Wuin, L., P. Mimi n W. Lishu, Intrtion twn oron n potssium in otton nutrition. At Poloi Sini, 24: Yrmiyhu, U., A. Bn-Gl, R. Krn n R. J. Ri, 28. Comin fft of slinity n xss oron on plnt rowth n yil. Plnt & Soil, 34: Riv Jun, 12, 214; pt for printin Jnury, 5, 215.