Amerin-Eursin J. Agri. & Environ. Si., 12 (7): 901-913, 2012 ISSN 1818-6769 IDOSI Pulitio, 2012 DOI: 10.5829/idosi.ejes.2012.12.07.1781 Effets of Plnting Dte nd Wter Defiit on Quntittive nd Qulittive Trits of Flx Seed Mohmmd Mirshekri, Rez Amiri, Hmmid Irn Nezhd, Seyeed A Sdt Noori nd Omid R. Zndvkili College of Aourihn, University of Tehrn, Irn Astrt: When ere is shortge for ville wter, low irrigtion stress is one meod to mintin produtivity. Therefore, study ws onduted to determine e effet of plnting dte nd irrigtion stress on two spring vrieties of flxseed. The experiment ws onduted s strip split plot sed on rndomized omplete lok design wi ree replitio during spring 2008 in University of Tehrn College of Aourihn, Irn. The highest plnt height (60.3 m), primry rnh numers per plnt (4.46), psule numers per plnt (65.9), seed numers per psule (5.78), seed yield (1763 kg/h), iologil yield (5935 kg/h), hrvest index (29.9 ), oil perentge (41), oil yield (718 kg/h), protein yield (361 kg/h), linoleni perentge (48.4) nd linolei perentge (18.36) were otined in first sowing dte nd under full irrigtion wheres, y lter sowing dtes nd limited irrigtion stress espeilly t flowering nd grin filling stges, is hrters were redued. The most oil yield (454 kg/h) nd linolei (18.81) id perentge were otined from serende vriety, wheres Lirin vriety hd e highest oil perentge (42.25), linoleni (47.9) nd olei (24.1) ids perentge. In is study, sowing dte ws very importnt mngement tool in minimizing e negtive impt of high temperture nd moisture stress during e ritil flowering nd seed filling periods. Key words: Ftty ids Limited irrigtion Oil yield Sowing dte INTRODUCTION ultivted in lmost ll ontinents wi temperte limtes [2]. Higher growing seson tempertures n hve The world popultion is projeted to eome drmti impts on griulturl produtivity, frm stggering 8.3 illion y 2030 from out 6 illion tody, inomes nd food seurity [6]. Dely in sowing led to n whih will ggrvte food ieurity espeilly in e inrese in environmentl temperture during developing ountries [1]. The ility of griulture to reprodutive grow of rop resulting in lower seed support growing popultion hs een onern nd qulity [7]. Wter stress is oidered one of e most ontinues to e on high priority on e glol poliy importnt ftors limiting plnt performne nd yield in gend. Flxseed (Linum usittissimum L.) is e six world nd impt on grow, lef photosynesis nd lrgest oilseed rop in e world nd is one of e oldest yield flxseed [8]. The highly positive effet of irrigtion ultivted plnts. Lieed type flx is reltively short on seed onfirms e key role of supplementry irrigtion plnt whih produes mny more seondry rnhes t ritil grow stges, prtiulrly seitive to wter ompred to e fier type [2]. Flx seed, ontining stress [9]. Mny grin rops hve little yield respoe to mixture of e ftty ids, is rih in two essentil ftty wter stress during vegettive stge nd during lte ids, lph-linoleni id nd linolei id, to use flx oil reprodutive or grin fill grow stges. However, rops in food pplitio where stility is essentil [3]. re seitive to wter stress during reprodutive grow Lieed oil is used in e mnufturing of pints nd stge nd yields will e impted during is time period vrnish, oil lo nd linoleum [4]. Alough flx is [10]. Under ese onditio, optiml sowing dtes nd oidered to e ool seson rop, ir temperture supplementl irrigtion t reprodutive stges, i.e. elow 10 C in e spring my inhiit grow nd flowering nd seed filling periods ould e of gret development, whih n dely flowering [5]. Flx is mngement option to lessen e negtive spets of Corresponding Auor: Mohmmd Mirshekri, College of Aourihn, University of Tehrn, Irn. 901
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 temperture nd drought stress. Sine wter resoures in determintion. Susmples were dried t 105 C for rid nd semi rid environments re limited is study moisture determintion. Seed yield ws djusted to 9% imed to evlute e influene of irrigtion nd ree moisture ontent nd ll oer mesurements were sowing dtes on lieed. reported on dry weight sis. Twenty plnts were rndomly olleted from e entrl six rows wi edging MATERIALS AND METHODS shers (0.1m utting wid) nd e following hrteristis were reorded for eh plot; Plnt height The study ws rried out in Agriulturl Reserh (m), primry rnh numer, psule numer per plnt, Centre, University of Tehrn, Aourihn Fulty of seed numer per psule, ousnd seed weight (g), seed Agriulture, in e sou-west of Tehrn (Lt. 35, 28'; 1 1 yield (kg h ), iologil yield (kg h ), hrvest index Long. 51, 44' nd elevtion 1280 m), Irn, s strip split (%), oil perentge oil yield (kg h 1 ), protein perentge, plot sed on rndomized omplete lok design wi 1 protein yield (kg h ), linoleni, linolei, olei, steri nd ree replites during spring 2008. The tretments plmiti ids perentge. Seeds were reshed y hnd omprised four limited irrigtion: norml irrigtion (I 0) -2 nd weight of seed (g m ) ws reorded. Plots were during e growing period (I 0: irrigtion fter 60 mm hrvested t mturity nd seeds were dried to uniform evportion from lss A pn) s ontrol, limited moisture ontent for 24-48 h t 75-80 C. Oil ontent ws irrigtion fter 150 mm evportion from stem elongtion determined using nuler mgneti resonne [11]. To (I 1), flowering (I ) 2 nd grin filling (I ) 3 just for one estimte protein ontent, nitrogen onentrtion ws irrigtion intervl nd ree sowing dtes (20 April, 10 determined using Tehnionutonlyzer [12]. A ftor My nd 30 My) s min plots nd vriety t two of 5.46 ws used to onvert nitrogen into rude protein levels (Lirin nd Serende) s suplots. Soil moisture ontent [13]. Seed smples were tken for totl ftty id determined grvimetrilly using ugers. All tretments nlyses. Totl ftty id ontent ws nlyzed y using were irrigted wi equl mount for eh time, whih ws meod modified y Wu et.l. [14]. In is meod seed mesured wi e help of 15 m rot Prshll flume smples were soked in 2 ml of 2% sulphuri id in dry fixed in e irrigtion hnnel. The dt for dy leng (h), menol for 16 h t room temperture, followed y 80 min temperture ( C), reltive humidity (%) nd preipittion of heting t 90 0C to onvert e ftty ids into meyl (mm) were otined from Vrmin meteorologil derivtives (FAMEs). Meyl heptdenote (17:0-ME) susttion (Fig. 1). Vrmin is loted in e entrl ws dded s n internl stndrd. The FAMEs were regio of Irn nd hs men nnul temperture of 27 C extrted in 2 ml wter nd 3 ml hexne nd en nd verge rinfll of 170mm. Soil smples were tken determined y gs liquid hromtogrphy (GLC). The (0-30 m) efore sowing nd soil nlysis results showed ftty id meyl ester omposition ws nlyzed y t it ws silty lom in texture wi ph of 7.28, ontined using Vrin 3400 gs hromtogrphy equipped wi 0.75% orgni mtter; totl nitrogen of 0.09 ppm, Supelovx-10 fused sli pillry olumn (30 m x 0.25 µm ssumle phosphorus of 4.8 ppm, exhngele film ikness). The olumn s initil temperture ws kept potssium of 390 ppm wi no slinity prolems t 160 C for 15 min so t in is temperture n inrese (E.C. = 1.8 ds.m 1 ). On e sis of soil nlysis, 40 kg ould our t e rte of 5 C min-1. The tempertures of 1 1-1 h ure, 40 kg h mmonium phosphte nd 20 kg h e injetor nd e dedetor (FID) were 240 C nd potssium sulfte fertilizer were pplied to e site nd 280 C, respetively. The rrier gs ws nitrogen wi hrrowed efore seeded preprtion. Nitrogen ws 1 flow rte of 1-2 ml min. Split rtio ws djusted to 30 ml pplied in two pplitio s split; hlf efore sowing min 1. The injeted volume of e smple ws 1 µl. Ftty nd e remining hlf ws pplied top dressed t flower- ids were identified y retention time reltive to t of 2 ud-visiility stge. The re of eh plot ws 10 m n uenti stndrd. The FAMEs were identified y oisting of eight rows, 5 m long nd 25 m prt. Seeds ompring e retention times wi ose of e stndrds. were sown 4 m prt t out 2-3 m dep. A 1.0-m lley Ftty id ontent ws omputed s weight perentge of ws left round eh plot. Plots were over seeded nd e totl ftty ids y using e GC re ounts for susequently inned to finl plnt deity of out 100 vrious FAMEs. Anlysis of vrines of dt for eh -2 plnts m t seedling stge. Weeds were ontrolled y ttriute nd omined nlysis of e split plot desig 1 o Triflurlin (2.5 L h ) s pre plnt nd y hnd s in two yers were omputed using e SAS omputer needed. Seed yields were tken t mturity y hrvesting progrm [15]. F test in omined nlysis of e e enter two rows of eh plot for seed yield experiments ws rried out using expeted vlues of e 902
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 Fig. 1: Amient temperture, rinfll nd reltive humidity during flxseed growing seson of 2008 in Vrmin. men squres whih yer nd replition were ssigned s yield nd perentge, protein yield, linoleni nd linolei rndom vriles nd sowing dte nd limited irrigtion ids perentge of flx seed quired in e first sowing were oidered s fixed vriles. The Dunn's multiple dte git e lowest vlues of ese trits reorded rnge tests t 5% level of proility ws used to test from lst sowing dte (Tle 2). In e lst sowing dte signifint min effets. The MSTAT-C softwre pkge protein perentge, olei, steri nd plmiti ids ws used to test signifint intertion effets etween perentge inresed sttistilly. tretments [16]. Aumulted growing degree dys (GDD) were lulted y summing e dily degree dy vlues Effet of Vriety: The nlysis of vrines reveled ( C) otined y dding e mximum nd minimum signifint differenes etween o vrieties for ll tempertures for e dy, dividing y two nd sutrting flxseed trits (Tle 1). Serende produed more primry e se temperture, whih for flx seed is 5 C (Tle 4). rnhes pre plnt, psules numer per plnt, seed The oeffiient of liner regression eqution etween e numer per psule, hrvest index, oil yield, protein yield trits men s e dependent vriles nd grow degree nd perentge, linolei, steri nd plmiti ids dy of ll e grow seson of flx seed s e perentge ompred to Lirin vriety ut mximum oil independent vrile re lulted y SAS. perentge, linoleni nd olei ids perentge otined from Lirin (Tle 2). RESULTS Intertion effet of sowing dte nd limited irrigtion stress: The intertion effet etween sowing dtes nd Effet of Irrigtion Levels: All flx seed trits were irrigtion levels ws signifint for seed numers per signifintly ffeted y limited irrigtion stress in e psule, seed yield, iologil yield, hrvest index, protein nlysis of vrines, exept numer of primry rnhes perentge nd yield, oil perentge, linoleni, linolei nd pre plnt (Tle 1). The highest plnt height, numer of olei ids perentge (Tle 1). The highest vlue of primry rnhes pre plnt, psules numer per seed numers per psule, seed yield, iologil yield, plnt, seed numers per psule, seed yield, iologil hrvest index, protein yield, oil perentge, linoleni nd yield, hrvest index, oil yield nd perentge, protein linolei ids perentge ws quired for April 20 yield, linoleni nd linolei ids perentge of sowing dtes y ontrol irrigtion tretment, while more flxseed were otined from ontrol irrigtion tretment, protein nd olei ids perentges otined in limited while limited irrigtion stress during flowering nd seed irrigtion stress during grin filling on My 30 sowing filling stges resulted in lowest ese trits, dte (Fig. 2). respetively (Tle 2). Limited irrigtion stress during flowering hd e highest ousnd seed weight Intertion Effet of Vriety nd Limited Irrigtion ompred to oer irrigtion tretments while, more Stress: Vriety irrigtion intertion effet ws protein perentge, olei, steri nd plmiti id signifint for ousnd seed weight, iologil yield, oil perentge otined from limited irrigtion stress t seed nd protein yields (Tle 1). The est oil nd protein yield filling stge (Tle 2). ws otined from Serende vriety under norml irrigtion t ll grow stges git e lowest vlue Effet of Sowing Dte: Sowing dtes hd signifint quired under limited irrigtion stress t flowering nd effet on ll flxseed trits (Tle 1). The highest plnt grin filling stges of flx seed (Fig. 3). The highest height, numer of primry rnhes pre plnt, psules ousnd seed weight nd iologil yield reorded for numer per plnt, seed numer per psule, ousnd Lirin vriety y norml irrigtion t ll grow stges of seed weight, seed yield, iologil yield, hrvest index, oil flxseed. 903
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 Tle 1: Anlysis vrine for e effet of limited irrigtion stress, sowing dtes nd vriety on two spring vrieties of flxseed (r=3). Plnt Primry Cpsule Seed Thousnd Seed Biologil Hrvest height rnh numers numers seed yield yield index Protein S.O.V d.f (m) numer per plnt per psule weight (g) (kg/h) (kg/h) (%) (%) Blok 2 0.39 0.064 7.4 0.009 0.027 2451 7389 0.44 0.069 I 3 66.2 0.16 2691.5 1.1 5.45 2170090 56833002 389.1 9.13 E1 6 3.13 0.063 19.29 0.011 0.018 3973 15435 0.77 0.032 T 2 76 0.96 2615 2.46 3.16 2938588 6613602 629.2 101 E2 4 1.25 0.1 4.35 0.006 0.014 1358 6961 0.278 0.015 I T 6 2.35 0.025 37.41 0.137 0.32 9721.4 65862.5 18.32 3.26 E3 12 1.97 0.069 15.4 0.02 0.011 3021 12888 0.49 0.03 C 1 512 9.92 2576 6.35 4.87 740139 1936512 550 291 I C 3 1.83 0.059 19.41 1.02 0.096 10898.6 88395.3 0.383 0.05 T C 2 20.5 0.22 35.87 0.018 0.24 4031.4 16770.5 1.12 0.064 I T C 6 1.57 0.012 3.07 0.011 0.017 2021.1 5413.6 0.92 0.417 E4 24 4.96 0.189 32.53 0.029 0.01 4714 16659 0.692 0.058 Protein yield Oil Oil yield Linoleni Linolei Olei Steri Plmiti S.O.V D.f (kg/h) (%) (kg/h) id (%) id (%) id (%) id (%) id (%) Blok 2 184.8 0.16 297 0.066 0.004 0.078 0.008 0.002 I 3 93417 7.42 360493 6.06 1.67 8.37 0.37 0.129 E1 6 194.5 0.086 738 0.008 0.02 0.21 0.022 0.013 T 2 85900 39.7 539889 41.83 11.8 61.47 1.76 0.83 E2 4 35.7 0.022 252.8 0.065 0.041 0.13 0.015 0.007 I T 6 812.1 1.6 1345.6 0.47 0.25 0.766 0.03 0.02 E3 12 149 0.045 500 0.047 0.018 0.081 0.027 0.016 C 1 143831 458.9 11453 69.5 83.1 15.32 9.14 0.82 I C 3 1655.8 0.22 2362.7 0.018 0.023 0.007 0.027 0.011 T C 2 1234.5 0.34 956.3 0.169 0.046 0.638 0.084 0.097 I T C 6 155.8 0.097 382.4 0.049 0.0086 0.12 0.01 0.11 E4 24 237.5 0.087 777 0.064 0.029 0.128 0.273 0.008 p = 0.05; p = 0.01; : non signifint; D.f: degrees of freedom; I: Limited irrigtion stress tretments; T: Sowing dte tretments; C: Vriety tretments. Tle 2: Dunn s men omprison test results for e effet of limited irrigtion stress, sowing dtes nd vriety (±SE) on flxseed. Plnt height Primry rnhes Cpsule numers Seed numers Thousnd seed Seed yield Tretments (m) numer per plnt per psule weight (gr) (kg/h) Irrigtion levels (I) I0 58.2±0.94 4.31±0.13 60±2.63 5.62±0.09 4.49±0.1 1535±67.8 I1 53.6±0.7 4.1±0.12 52.3±3.05 5.57±0.094 4.11±0.08 1242±76.9 I2 55.7±0.78 4.29±0.1 d 31.4±2.28 5.1±0.1 4.61±0.15 d 784±77.8 I3 56.7 ± 0.1 4.25±0.14 44.6±2.98 5.28±0.13 d 3.39±0.08 870±79.6 Sowing dte levels (T) T1 57.9±0.93 4.37±0.11 55.3±2.85 5.68±0.06 4.46±0.14 1392±62 T2 56±0.79 4.33±0.12 50.6±2.67 5.46±0.09 4.25±0.12 1214±69 T3 54.3±0.48 4±0.08 35.4±2.6 5.05±0.1 3.75±0.1 717±71 Vriety levels (C) C1 58.7±0.57 3.9±0.07 41.1±2.2 5.1±0.06 4.41±0.11 1006±69.7 C2 53.4±0.37 4.6±0.06 53.1±2.6 5.7±0.06 3.89±0.08 1209±72.2 904
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 Tle 2: Continue Biologil Hrvest Protein yield Oil yield yield (kg/h) index (%) Protein (%) (kg/h) Oil (%) (kg/h) Irrigtion levels (I) I0 5624±104 27.2±0.1 21.29±0.53 326±16.1 40.26±0.62 617±27.8 I1 4988±131 24.7±1.04 22.06±0.64 272±17.3 39.9±0.66 495±31 I2 d 4374±115 d 17.5±1.43 22.05±0.73 d 168±15.7 40±0.69 316±32.3 I3 4524±113 18.8±1.5 23.03±0.68 197±17.3 38.8±0.72 338±31 Sowing dte levels (T) T1 5315±106 26.02±0.9 20.5±0.45 287±15.7 40.8±0.53 565±24.2 T2 5022±111 23. 9±0.1 21.4±0.42 262±16.5 40.1±0.52 484±26.7 T3 4296±115 16.28±1.3 24.4±0.48 173±16.7 38.3±0.59 275±27.8 Vriety levels (C) C1 5042±113 19.3±1 20.1±0.32 196±12.1 42.25±0.19 428±30.6 C2 4714±111 24.8±1.03 24.12±0.31 285±15.2 37.2±0.23 454±28.5 Linoleni id (%) Linolei id (%) Olei id (%) Steri id (%) Plmiti id (%) Irrigtion levels (I) I0 47.39±0.32 17.93±0.28 23.11±0.29 5.15±0.1 6.25±0.05 I1 47.06±0.37 17.89±0.29 23.35±0.33 5.14±0.09 6.34±0.056 I2 47.04±0.4 17.82±0.33 23.43±0.4 5.13±0.11 6.34±0.057 I3 46.05±0.34 17.28±0.3 24.6±0.37 5.43±0.12 6.45±0.04 Sowing dte levels (T) T1 48.12±0.24 18.28±0.22 22.18±0.18 5± 0.09 6.21±0.04 T2 47.06±0.23 17.96±0.23 23.35±0.16 5.1 ± 0.09 6.27±0.03 T3 45.5±0.23 16.94±0.25 25.35±0.2 5.5 ± 0.08 6.56±0.02 Vriety levels (C) C1 47.9±0.22 16.65±0.12 24.09±0.23 4.86±0.05 6.23±0.04 C2 45.9±0.2 18.81±0.1 23.17±0.27 5.57±0.05 6.45±0.02 Men of eh group in olum of eh tretment wi similr letters re not signifintly different (Dunn 5%). I : Norml irrigtion t ll grow stges; 0 I : Limited irrigtion stress t stem elongtion stge; I : Limited irrigtion stress t flowering stge; I : Limited irrigtion stress t grin filling stge; T :20 1 2 3 1 April; T : 10 My; T :30 My; C : Lirin C : Serende. 2 3 1 2 Tle 3: Correltion oeffiients for e effet of limited irrigtion stress, sowing dtes nd vriety on two spring vrieties of flxseed (r=3). Plnt height 1.00 Primry rnhes -0.47 1.00 Plnt Primry Cpsules Seeds Thousnd Seed Biologil Hrvest height rnhes per plnt per psule seed weight yield Trits yield index Cpsules per plnt -0.009 0.55 1.00 Seeds per psule -0.22 0.71 0.89 1.00 Thousnd seed weight 0.52-0.17 0.05 0.04 1.00 Seed yield 0.17 0.45 0.95 0.84 0.37 1.00 Biologil yield 0.56 0.05 0.74 0.5 0.55 0.87 1.00 Hrvest index -0.02 0.58 0.94 0.93 0.27 0.96 0.73 1.00 Trits Protein (%) Oil (%) Protein yield Oil yield Linoleni id Linolei id Olei id Steri id Plmiti id Protein (%) 1.00 Oil (%) -0.95 1.00 Protein yield -0.08-0.16 1.00 Oil yield -0.5 0.28 0.88 1.00 Linoleni -0.97 0.89 0.18 0.59 1.00 Linolei 0.28-0.54 0.74 0.47-0.15 1.00 Olei 0.39-0.14-0.75-0.8-0.53-0.73 1.00 Steri 0.95-0.96 0.07-0.38-0.93 0.39 0.27 1.00 Plmiti 0.88-0.77-0.27-0.65-0.91 0.03 0.54 0.87 1.00 p= 0.05; p = 0.01 905
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 Tle 4: Flxseed growing period (Durtion) under different tretments of sowing dtes nd limited irrigtion stress in 2008. T1 T2 T3 ------------------------------------------- --------------------------------------------- ---------------------------------------------- Lirin I0 I1 I2 I3 I0 I1 I2 I3 I0 I1 I2 I3 Durtion(Dy) 94 89 79 82 87 82 71 76 73 65 53 58 GDD ( Cdy) 1702 1590 1382 1442 1686 1581 1323 1440 1500 1329 1053 1166 Serende Durtion(Dy) 102 98 89 91 96 91 79 85 79 73 63 67 GDD( Cdy) 1890 1791 1590 1631 1882 1581 1507 1646 1627 1500 1286 1329 Tle 5: Regression reltiohip etween grow degree dy nd some quntittive trits of flxseed during growing seson (pooled vlues for o vrieties). Primry Cpsules Seed numers Trits rnhes numer numer per plnt per psule Seed yield Biologil yield Oil yield Protein yield 2.37-60.2 2.33-1933 1176-729 -421 0.001 0.07 0.002 1.99 2.43 0.77 0.44 2 R 0.34 0.91 0.77 0.90 0.53 0.80 0.92 Fig. 2: Dunn s men omprison test for e intertion effets of sowing dtes nd limited irrigtion stress (±SE) on some of flxseed trits. Men of eh tretment wi similr letters re not signifintly different (Dunn 5%). I 0: Norml irrigtion t ll grow stges; I 1: Limited irrigtion stress t stem elongtion stge; I 2: Limited irrigtion stress t flowering stge; I 3: Limited irrigtion stress t grin filling stge; T 1: 20 April; T 2: 10 My; T 3: 30 My. 906
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 Fig. 3: Dunn s men omprison test for e intertion effets vriety nd limited irrigtion stress (±SE) on some of flxseed trits. Men of eh tretment wi similr letters re not signifintly different (Dunn 5%). I 0: Norml irrigtion t ll grow stges; I 1: Limited irrigtion stress t stem elongtion stge; I 2: Limited irrigtion stress t flowering stge; I 3: Limited irrigtion stress t grin filling stge; C 1: Lirin; C 2: Serende. Fig. 4: Dunn s men omprison test for e intertion effets of vriety nd sowing dte (±SE) on some of flxseed trits. Men of eh tretment wi similr letters re not signifintly different (Dunn 5%). T 1: 20 April; T 2: 10 My; T 3: 30 My; C 1: Lirin; C 2: Serende. Fig. 5: Regression reltiohip etween grow dy degree wi hrvest index, linoleie nd oleie ids of flxseed during growing seson (pooled vlues for o vrieties). 907
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 Intertion Effet of Vriety nd Sowing Dte: DISCUSSION The intertiion effet etween vriety nd irrigtion tretments on plnt height, ousnd seed weight, protein Plnt Height: In is study, plnt height signifintly yield, oil perentge, olei nd plmiti ids perentge differed under different irrigtion nd sowing dte were signifint (Tle 1). Lirin vriety in e first sowing tretments. This result ould e explined y differenes produed e highest vlues for plnt height, ousnd in e weer onditio nd supplementry irrigtion seed weight nd oil perentge, while e minimum of from stem elongtion stge to lte grin distriution ese trits were oserved from Serende vriety in e (Fig. 1, 4). Our results re in greement wi ose lst sowing dte (Fig. 4). The highest protein yield otined y Snkri [17], who found t humidity nd otined from serende in e first sowing dte wheres, temperture differenes used wide vrition etween e minimum otined y lirin in e lst sowing dte. flxseed ultivrs for men plnt height. Ahlwt & Lirin in e lst sowing produed e most olei id Gngih [18] noted t limited irrigtion stress during perentge while, e highest plmiti id perentge e grow stges redued e plnt height. Wi delyed oserved y serende in e first sowing dte. sowing, high temperture hste e development, shorte e durtion nd redues e grow per dy Correltion Anlysis Between Flxseed Trits: The from sowing to hrvest us redues plnt height (Tle orreltion oeffiient (r) of seed yield wi yield 4, 2). In oer reports, wter nd temperture stress hve omponents were highly signifint nd positive. Highly een shown to redue plnt height in lieed [19] y signifint nd positive orreltion ws noted in seed inresing respirtory losses. yield wi numer of psules plnt, seed numer per psule, iologil yield nd hrvest index (Tle 3). Primry Brnhes Numer: Delying in sowing nd Correltion nlysis of reltio mong ftty ids, oil nd wter stress, led to derese numer of primry rnhes protein perentge of lieed oil is reported in Tle 4. per plnt (Tle 2). Numer of primry rnhes per plnt The dt indited t olei id ontent hd is genetilly ontrolled hrteristi [20] however signifintly negtive orreltion wi linolei id plnting geometry my hve resonle effet on e wheres steri id hd signifintly positive development of rnhes [21]. Rhimi et l. [221] reported orreltion wi plmiti id git negtive t high temperture redued e numer of tillers, orreltion wi linoleni id. Oil perentge hd euse e period etween esis nd senesene ws positive orreltion wi linoleni id nd signifintly urtiled y reltively higher temperture. negtive orreltion wi protein perentge. Olei id hd signifintly positive orreltion wi plmiti nd Cpsule Numers per Plnt: The sowing dtes identified steri ids ut negtive orreltion wi protein nd oil optimum psule numer per plnt quired y full yields. irrigtion on April sowing dte (Tle 2). The lowest psule numers ws oserved wi lter flowering my Regression Anlysis Between Grow Degree Dy e due to temperture effet on pollintion, ovry (GDD) nd e Flxseed Trits: The reltiohip etween survivl in delyed sowing dtes. These results ffirmed grow degree dy (GDD) (x) nd e flxseed trits (Y) y Ford [23]. Lieed is suseptile to wter stress t e ws signifint for primry rnh numer per plnt, seedling stge, t flowering nd during erly seed psule numer per plnt, seed numer per psule, seed development [24]. It ppers t wter stress hmpered yield, iologil yield, hrvest index, oil nd protein yield, flowering nd redued e proility of developing linoleie nd oleie ids perentge in pooled vlues for flower to pod nd its ourrene during flowering nd pod lirin nd serende vrieties (Tle 5, Fig. 5). A regression formtion resulted in pod ortion [25]. nlysis reveled t flxseed trits were inresing wi e inrese of GDD. The highest vlue of GDD ws Seed Numers per Cpsule: At is study ws produed reorded in e first sowing dte ompred to seond nd mximum seed numer per psule wi full irrigtion ird sowing dte of flxseed in e o vrieties. when sown on April 20 nd on My 10 sowing (Tle 2, The results reveled t durtion (dys) for e mturity Fig. 2). These results ffirmed y Prsd nd Shrm [26]. of flxseed y norml irrigtion were highest nd redued Flowering ws e most seitive stge to wter stress, wi limited irrigtion stress t stem elongtion, flowering proly due to suseptiility of pollen development, nd grin filling stges (Tle 4). nesis nd fertiliztion led to lower seed yield [27]. 908
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 Thousnd Seed Weight: Men ousnd seed weight & Zimmermn (1967), who found e minimum hrvest depended on sowing dte nd ultivr, s o ftors index t higher temperture. Results show higher interted signifintly wi irrigtion levels (Fig. 2, 3 4). hrvest index y full irrigtion (Tle 2, Fig. 2). Results of Thousnd seed weight losely relted to green is study is in greement wi e findings of Pndey et photosyneti re whih is respoile for l [32] who stted e reson of hrvest index redution rohydrte formtion, grin filling nd finl grin yield. t severe drought stress is e higher seitivity of Results show higher seed yield under full irrigtion reprodution grow to undesirle onditio in (Tle 2, Fig. 2, 3). This inrese in yield ould e sried ompred to genertive grow. to fvorle moisture onditio resulting from irrigtio t ritil phenologil stges of initition of flowering Protein Perentge nd Yield: The hnges of protein nd seed filling. Suh finding oisted in wi results of perentge in e present study were proly dependent Ahlwt & Gngih [18] nd Rhimi & et l [22]. on e intertion of ese hrters wi environmentl For spring- dely sown seed flxseed, ere is less ftors suh s wter supply nd high temperture during possiility of ompetion due to e shortened seed filling stges flxseed (Fig. 2, 3, 4). These results vegettive phse, however, e derese in men seed ffirmed y [33]. Growing onditio nd rop weight in e present study slightly ws ompeted for mngement prties lso influene protein perentge y n inrese in e numer of psules per plnt. [34]. The lower protein yield otined in My 9 nd espeilly My 30 sowing dtes (Tle 2, Fig. 4) ould e Seed Yield: Seed yield ws e mximum in first sowing due to higher tempertures, whih ourred during e dte nd deresed wi delyed sowing dtes (Tle 2, seed filling period t resulted in redution of seed yield. Fig. 2, 3) whih my e due to high temperture effet on Sowing dte is mjor determinnt of seed qulity nd pollintion, ovry survivl or seed development. Sowing quntity [35]. Wter defiit during flowering nd seed dte nd irrigtion studies wi flxseed identified filling stges redued protein yield (Fig. 2, 3). Singh [36] mximum seed yield from n erly sowing wi stted t is ehvior might e srile to yield supplementry irrigtion from flowering to lte grin fill potentil nd e intertion of ese hrters wi [28]. This inrese in yield ould e sried to fvorle environmentl ftors suh s wter supply. moisture onditio resulting from irrigtio t ritil phenologil stges of initition of flowering nd seed Oil Perentge nd Yield: Climti onditio ould e filling. A similr inrese in yield wi irrigtion ws lso oidered s determining ftor for oil perentge nd reported y Husin et l [29]. yield. In dely sowing, e redution of oil perentge nd yield (Tle 2, Fig. 4) ws due to unfvorle weer Biologil Yield: The results showed t e optimum onditio (Fig. 1). This my e due to t inresed sowing dte ws from e seond hlf of April to My10 temperture nd wter stress during seed filling ws sowing dte (Tle 2, Fig. 2). This result in gree wi mjor use of redued oil perentge nd yield. Similr results of [30]. In omprison, iologil yield under results hve een reported y Grsid [30] nd Silv [37]. limited irrigtion stress t flowering nd seed filling stges Experiments rried out in ontrolled onditio showed ws signifintly lower n oer irrigtion tretments t high tempertures during e ripening phse redue (Tle 2, Fig. 2, 3). These results ffirmed y Ev [31]. oil yield nd qulity of flxseed [38]. In e present study, It ppers t wter stress hmpered flowering nd wter stress used redution in e oil perentge of redued e proility of developing flower to psule o ultivrs (Tle 2, Fig. 2), whih is in greement wi nd its ourrene during flowering nd psule formtion e results of Sosulski & Gore [39] for lieed. The est oil resulted in psule ortion nd erefore produe more yield ws otined from full irrigtion tretment followed yield nd iologil yield. y limited irrigtion stress t stem elongtion stge (Tle 2, Fig. 3, 4). This inrese in yield ould e sried to Hrvest Index: Hrvest index ws e mximum in first fvorle moisture onditio resulting from irrigtio t sowing dte nd deresed wi delyed sowing dtes ritil phonologil stges of initition of flowering nd (Tle 2) euse e grin formtion stges oinided seed filling. It ppers t wter stress hmpered wi fvorle lower temperture, while y lte-sowing flowering nd redued e proility of developing dte flxseed suffered severely from het stress during flower to psule nd its ourrene during grin formtion led to norml development nd poor flowering nd psule formtion resulted in psule prodution. These results oinide wi finding of Dying ortion [25]. 909
Am-Eurs. J. Agri. & Environ. Si., 12 (7): 901-913, 2012 Ftty Aids: The hnges in ftty ids omposition in orreltion of psule numer per plnt nd seed numer e present study were proly due to e effet of wter per psule wi seed yield. These findings orrespond defiits nd high tempertures during e seed-filling wi results of Alrehtsen & Dying [51], who found period wi lte sowing nd drought tretments. higher psule numer per plnt nd seed numer per Temperture is generlly oidered to e e most ritil psule inrese seed yield. Rd et l. [52] reported t limti ftor ffeting qulity [40]. Cool limti ere were positive orreltion etween seed yield nd onditio dely e mturity of e flxseed nd us seed weight nd iologil yield. This study lso proved provide longer period for oil nd ftty id synesis t ere is positive nd losely orreltion etween [41]. The results of present study showed derese in hrvest index nd seed yield under onditio limited linoleni id perentge during e lst sowing dte irrigtion stress. These results gree wi finding of (Tle 2, Fig. 2). These results oinide wi finding of Bldini & Vnnozzi [53]. Strong negtive orreltion ws [42,43], who reported high temperture during seed oserved etween oil nd protein perentge in seeds, development deresed linolei nd linoleni id in is result is in greement wi e finding of Dwivedi et severl oilseed rops. Cnvin [44] reported t e ftty l 1990). The inverse reltiohip etween olei nd id ompositio of e oilseed rpe, sunflower nd flx linolei id were reported y Prveen [54]. Besides, depended on temperture, when e plnts were grown linoleni id hd signifintly positive orreltion wi under lortory onditio, while sfflower nd stor oil perentge nd signifintly negtive orreltion wi oils were not ffeted. The perentge of olei, steri nd protein perentge. This reltiohip might e due to plmiti ids vried inversely wi e linoleni id environmentl ftors, espeilly temperture during e perentge. Steri nd olei ids inresed while linolei period of seed development nd mturtion. Limited nd linoleni ids deresed y low irrigtion stress irrigtion stress during flowering or psule-filling stges (Tle 2, Fig. 3). This results in oisted wi finding of my fvor inresed protein perentge nd erey Green [42] nd Wolf et l [45]. The olei/linolei rtio ws deresing oil perentge [55]. inresed due to wter stress t different grow stges nd mximum inrese ws oserved t e reprodutive Regression Anlysis Between Grow Degree Dy stge (Tle 2, Fig. 2, 4). Wter stress during e grin (GDD) nd e Flxseed Trits: Dely in sowing nd filling period used signifint inrese in e limited irrigtion stress led to more rpid development of olei/linolei rtio in high olei genotypes of sunflowers flxseed, deresed e dys from emergene to flowering [46]. This effet of high temperture nd wter stresses on nd to physiologil mturity, durtion of flowering nd olei nd linolei ids perentge my e ttriuted to seed filling nd deresed e opportunity of flxseed to e tivity of e enzyme?12 desturse [46,47]. In reover (Tle 4). Dy leng nd photoperiod re lso ontrst, Unger [48] found very little differenes in importnt ftors respoile for e different grow olei/linolei rtios in sunflower under different wter ehvior of grin flxseed (Fig. 1). Shortening of e regimes. The differenes in e results of e two studies growing yle derese e mount of rdition my e due to e imposition of drought t different interepted during e growing seson nd us totl dry grow stges. Ftty id omposition ws different in mtter t hrvest [38]. Stresses imposed t lter stge of lirin nd serende ultivrs (Tle 2). In oisted wi development redued sink size, shorten e durtion of our result Connor nd Sdrs [49] reported t ftty id seed filling nd deresed e opportunity of rop to omposition differs etween ultivrs due to hnges in reover. There ws positive liner reltiohip etween environmentl onditio. The olei/linolei rtio GDD nd ll of flxseed studied trits (Tle 5, Fig. 5). inresed due to wter stress t different grow stges These results re in oistent wi e findings of nd nd mximum inrese ws oserved t e reprodutive Bremner & Rdley [56] nd Turner [57]. stge. These results re not in greement wi finding of Bldini et l [50] who t reported e sturted ftty CONCLUSION id ontents (plmiti id nd steri id) in sunflower did not vry under different wter regimes. In summry, it is onluded t wter stress during lieed reprodutive grow stges prtiulrly flowering Correltion Anlysis Between Flxseed Trits: The nd psule formtion is ritil period t leds to results (Tle 3) show t e positive respoe yield of deresed most of flxseed trits. Our results reveled t flxseed to irrigtion ws due to e signifint positive for lieed prodution, sowing in erly April is preferle 910
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