Emirtes Journl of Food nd Agriculture. 2016. 28(2): 136-142 doi: 10.9755/ejf.2015-05-291 http://www.ejf.me/ REGULAR ARTICLE Growth nd yield of three sunflower hyrids cultivted for two yers under mediterrnen conditions Yolnd Pptheohri 1, Ilis S. Trvlos 1, Pngiot Ppstylinou 1, Ionnis G. Argyrokstritis 2, Dimitrios J. Billis 1 1 Agriculturl University of Athens, Fculty of Crop Science, Lortory of Agronomy, 75, Ier Odos st., 11855 Athens, Greece, 2 Agriculturl University of Athens, Division of Wter Resources Mngement, 75, Ier Odos st., 11855 Athens, Greece ABSTRACT Sunflower (Helinthus nnuus L.) is glolly one of the most importnt oil crops. A 2-yers field study ws conducted to evlute growth, grin nd oil productivity of three sunflower hyrids (PR64E83, Oleko nd PR63A90). Plnt height, numer of green leves, weight of 1000-grins nd grin numer were significntly ffected y the interction of yer nd sunflower hyrid. Grin yield resulted to differences rnged mong 13 nd 34 % etween the two yers. In 2009, Oleko nd PR63A90 were the most productive hyrids regrding seed (8210 nd 7500 kg/h, respectively) nd oil (2960 nd 2950 kg h -1, respectively), while PR63A90 ws the significntly more productive hyrid during the second yer (2010). Hyrids such s Oleko seem idel for high grin nd oil yield (with high concentrtion of monounsturted ftty cids); however they fit etter to crop rottion, proly due to high phytotoxicity of their residues which reduces the yield of the second yer. On the contrry, the ility of some non high-oleic hyrids such s PR63A90 to keep high grin yield even in the second yer of their cultivtion in the sme field is clerly very desirle trit nd it should e further tested, since it cn result to very high oil yield. Keywords: Sunflower; High-oleic hyrid; Seed oil yield INTRODUCTION Sunflower (Helinthus nnuus L.) is glolly one of the most importnt rle crops minly grown for edile oil, due to its high oil content, high non sturted ftty cids content nd sence of cholesterol (Lelnd, 1996; De l Veg nd Hll, 2002). Ltely, severl reeding ttempts re towrds the direction of the development of sunflower cultivrs with high oleic cid concentrtion (Flgell et l., 2002; Mohmmdi et l., 2013). These cultivrs re considered to hve high oxidtive stility of their oil (Fuller et l., 1967), which is desirle especilly for processing nd storge. Moreover, diet rich in monounsturted ftty cids hs mny dvntges to offer (Grundy, 1986; Delpnque, 2000). In ddition, sunflower is not only n importnt oil crop ut is lso cultivted for io-energy purposes such s offering n eco-friendly lterntive to diesel fuel (Antolin et l., 2002; Brnwl nd Shrm, 2005). In generl, it could e sid tht sunflower is mong the most cosmopolitn crops with mny uses nd high dptility to diverse envrionments (Berd nd Geng, 1982). In Greece, sunflower is minly grown in the centrl nd northern prt of the country in rottion with plnts such s winter cerels nd legumes (Kllivroussis et l., 2002). As shown in worldwide level, mny fctors such s weeds nd wter deficit cn cuse sustntil yield losses to sunflower nd consequently, the cultivtion of the most suitle hyrids is of mjor importnce (Unger, 1990; Brecci et l., 2011). All these fctors comined with the specific soil nd climtic conditions of ech re mke the predictions regrding the productivity of ech sunflower hyrid even more difficult nd the comprtive evlution of severl hyrids under the sme conditions of mjor importnce, however reltive dt re rther indequte. Therefore, the min ojective of the present study ws to evlute - under the sme conditions - the growth nd productivity (grin nd oil yield nd oil concentrtion) of three sunflower hyrids lredy cultivted in Greece. In prticulr, this study ws conducted in order to see how high-oleic hyrid grows nd yields in comprison with conventionl hyrids under low-input conditions. *Corresponding uthor: Yolnd Pptheohri, Agriculturl University of Athens, Fculty of Crop Science, Lortory of Agronomy, 75, Ier Odos st., 11855 Athens, Greece, E-mil: pptheohri@u.gr Received: 25 My 2015; Revised: 03 Novemer 2015; Accepted: 04 Novemer 2015; Pulished Online: 02 Jnury 2016 136 Emir. J. Food Agric Vol 28 Issue 2 2016
MATERIALS AND METHODS Study loction The field experiment ws conducted during 2009 nd 2010 in the experimentl field of the Agriculturl University of Athens (37 ο 59 12 N, 23 ο 42 96 E). Soil ws cly lom (CL), the physicochemicl chrcteristics of which (0- to 15-cm depth increment) were cly 352 g/kg, silt 457 g/kg, snd 191 g/kg, ph (1:2 H 2 O) 8.2, 1.75 g/kg totl nitrogen, 0.034 g/kg ville phosphorus (P-Olsen) nd 0.88 g/kg ville potssium. EC ws 2700 μmhos, CCO 3 330 g/kg nd orgnic mtter content 24.4 g/kg (Wlkley nd Blck, 1934). Men monthly temperture nd precipittion dt recorded ner the experimentl re re shown in Tle 1. Experimentl detils Three sunflower hyrids, nmely PR64E83 (Pioneer), Oleko (Syngent) nd PR63A90 (Pioneer) were plnted on 27 April 2009 nd 4 My 2010. These sunflower hyrids re mong the most cultivted ones in Greece, while one of them (Oleko) is known s high oleic hyrid. They were seeded y hnd in 75-cm rows with distnces within rows of 20 cm. Before plot estlishment ech yer, 27.5 kg N h -1, 16.4 kg P h -1 nd 31.3 kg K h -1 were incorported with hrrow into the soil (inorgnic fertilizer 11:15:15). Plnt emergence egn 5 dys fter sowing nd ws completed within 9 dys fter sowing. The experiment ws set up on n re of 253 m 2 ccording to the split plot design (rndomized complete lock) with three replictes nd three tretments (sunflower hyrids). The plot size ws 5 m 3 m. The distnce mong plots ws 1 m nd the sme distnce ws lso kept mong replictes. Weeds were controlled during the growing seson y severl cultivtion nd hnd-hoeing tretments. Irrigtion nd other common culturl prctices were conducted s needed during the growing sesons. The totl wter quntity pplied ws 292 mm of H 2 O. Mesurements Five mesurements of plnt height, numer of leves, lef re index (LAI), dry weight of leves, stems nd Tle 1: Men monthly rinfll nd temperture during the field experiments in 2009 nd 2010 Month Rinfll (mm) Temperture ( C) 2009 2010 2009 2010 Mrch 80.4 11.8 12 13.4 April 29.4 0.2 16 17 My 7.0 7.6 21.4 21.1 June 0.4 15.8 25.7 25.1 July 0.8 0 28.7 28.7 August 0 0 28.4 29.8 Totl 118 35.4 inflorescence (if ny) were tken from plnts in the three center rows of ech plot t 45, 59, 75, 88, 106 nd 45, 59, 76, 90, 100 dys fter sowing (DAS) for 2009 nd 2010, respectively. Lef re ws estimted y mens of DT-re meter (Delt-T Devices Ltd, Burwell Cmridge, UK), while dry weights were mesured fter 24 h t 80 o C (Mirlles et l., 1997). Plots were hrvested y hnd on 31 August 2009 nd 26 August 2010 (127 nd 114 DAS, respectively). Yield (grin nd oil) ws determined nd mesurements on the stem dimeter, seed numer nd dry weight of 1000 seeds were lso tken. Seed moisture t hrvest ws 5 % s recorded y MT-PRO (Frmex). Moreover, ftty cids were determined ccording to the interntionlly ccepted methodologies. Oil concentrtion ws determined y mens of the crude ft method s proposed y the Assocition of Officil Anlyticl Chemists (AOAC, 1990). Oil yield ws clculted y multiplying seed yields y the concentrtion of oil in seeds. Sttisticl nlysis Anlysis of vrince (ANOVA) ws conducted for ll dt nd differences etween mens were seprted using Fisher s LSD test t P < 0.05. All sttisticl nlyses were conducted using the Sttistic 12 softwre pckge (SttSoft, Inc. 2300 Est 14th Street, Tuls, OK 74104, USA). RESULTS AND DISCUSSION The nlysis of vrince of our dt reveled tht mny growth nd yield prmeters of sunflower were significntly ffected y the sunflower hyrid nd the yer (Tle 2). In prticulr, plnt height, numer of green leves, weight of 1000-grins nd grin numer were significntly ffected y the interction of yer nd sunflower hyrid. The yer on itself ws lso significnt fctor for lmost ll the crop chrcteristics, while it hd no significnt effect on the oil content. Moreover, hyrid s effect ws significnt for ll grin yield nd iomss prmeters of sunflower (Tle 2). The time course of plnt height of sunflower is given in Fig. 1. In generl, the time course did not exhiit mjor fluctutions during the oservtion period. The height of sunflower plnts reched its mximum vlues t 75 nd 88 DAS for 2009 nd 2010, respectively. However, it hs to e noted tht in oth yers sunflower plnts lmost douled their height in the period from 45 to 59 DAS. Moreover, even in most cses there were no significnt differences etween the three hyrids (p>0.05), Oleko ws the hyrid with the higher first growth (until 45 DAS) in oth yers. In generl, plnt height is considered to e geneticlly determined chrcteristic; however, it is significntly ffected y soil nd climtic conditions (Pilli et l., 1995). Emir. J. Food Agric Vol 28 Issue 2 2016 137
Tle 2: Anlysis of vrince for hyrid (H) nd yer (Y) effects on plnt height, numer of leves dry weight of leves, inflorescences, 1000 seeds, numer of seeds nd oil content of seeds t hrvest Source df Plnt height Numer of green leves DW of leves DW of inflorescences 1000 grin weight Numer of grins Oil concentrtion H 2 1.83 ns 2.38 ns 12.48*** 4.79** 5.36** 20.18*** 0.41 ns Y 1 21.19*** 77.51*** 7.03** 52.72*** 169.84*** 37.29*** 3.61 ns H Y 2 2.35* 12.01*** 3.05 ns 0.1 ns 3.45* 7.38*** 1.22 ns F test vlues re shown, *P<0.05, **P<0.01, ***P<0.001, ns=not significnt Fig 1. Time course of plnt height of the three sunflower hyrids during the two experimentl periods (: 2009 nd : 2010). Verticl rs denote stndrd errors of the mens. Vinisree et l. (1998) hve shown tht higher plnts re strongly correlted with higher yields, too. However, this ws not true in our cse, since the yer my ply mjor role. Regrding the numer of green leves, there were lso some interesting oservtions (Fig. 2). The rpid erly growth of Oleko resulted to significntly higher lef numer t 45 DAS in 2009, while in 2010 there were not ny significnt differences during the first growth stges. In ddition, from out 75 DAS plnts showed decresing trend of the numer of green leves, since mny of them were in senescence nd dried. In the second yer, this reduction of the numer of green leves during the lst mesurement ws drmtic, rnging from 80 to 100% for ll three hyrids nd my hve een due to comintion of wter deficit nd high ir tempertures. Fig 2. Time course of the numer of the green leves for the three sunflower hyrids during the two experimentl periods (: 2009 nd : 2010). Verticl rs denote stndrd errors of the mens. In Fig. 3, the time course of LAI is lso shown. In 2009, LAI ws higher for Oleko in most mesurements, while the hyrids PR63A90 nd PR64E83 hd higher vlues of LAI thn Oleko during the second yer. This finding could e ttriuted to the different response of ech hyrid under the different climtic conditions of ech yer nd my e relted with differences in the finl yields. The time course of the weight of the inflorescences ws lso rther expected s shown in Fig. 4. However, there ws significnt difference mong the two yers with less grown inflorescences during 2010 compred with the previous yer. Another interesting finding hs to do with the high vlues for Oleko hyrid during 2009 nd the low vlues in 2010 compred to the other two hyrids. The results of the present study hve shown some significnt differences mong yers nd hyrids regrding yields nd yield components. It hs to e noted tht 138 Emir. J. Food Agric Vol 28 Issue 2 2016
Fig 3. Time course of LAI for the three sunflower hyrids during the two experimentl periods (: 2009 nd : 2010). Verticl rs denote stndrd errors of the mens. seed yield resulted to differences rnged mong 13 nd 34 % etween the two yers (Tle 3). There hs een decrese in the yield of 1000-grins in the second yer for ll these hyrids. This could e minly ttriuted to the lower growing seson (hrvest t 127 nd 114 DAS for 2009 nd 2010, respectively) nd therefore mturity period, too. The significntly lower grin yield of Oleko nd PR64E83 in 2010 is certinly relted with the lower weight of 1000-grins nd the lower grin numer per hed. Grin formtion is intensely ffected y temperture nd rdition condition during pollintion. These results re in full greement with De l Veg et l. (2002), reporting tht the decline of grin numer is cused y poor grin formtion during lte sowing dtes which re relted with unfvorle environment condition on pollintion period. It is well-known tht severl environmentl fctors during flowering nd seed-filling cn significntly ffect seed yield (Petcu et l., 2001; Monotti, 2003; Ali et l., 2009). However, even in this cse there re some differentitions, due to significnt hyrid nd yer effects nd their interctions. In our study, especilly in 2010, PR63A90 resulted to significntly higher yield thn the other hyrids (Tle 3). This different response of ech hyrid is clerly relted with the genotype nd the gronomicl chrcteristics of ech hyrid nd hs een previously reported y Trvlos et l. (2014). Oleko nd PR64E83 prefer erly sowing, while in Fig 4. Time course of the dry weight (DW) of the inflorescences for the three sunflower hyrids during the two experimentl periods (: 2009 nd : 2010). Verticl rs denote stndrd errors of the mens. our study, PR63A90 proved to e more flexile in respect with sowing dte. Moreover, phenomen such s llelopthy my hve een involved. It hs een oserved tht sunflower crop hs hrmful effects on the succeeding crops in multiple cropping systems (Irons nd Burnside, 1982; Nrwl et l., 1999). Studies hve indicted tht the hrmful effects of sunflower on other plnt species were due to llelopthic effects, while it is lso crop tht exhiits utotoxicity. Its growing plnts inhiit the germintion nd growth of weeds nd succeeding crops due to ccumultion of phytotoxins from root exudtes nd decomposing crop residues (Lovett, 1982; Rwt et l., 2013). Indeed, sunflower contins severl compounds like terpenoids nd phenolics which re hrmful ginst other plnts (Azni et l., 2003; Mcís et l., 2004; Anjum nd Bjw, 2005). In recent study, Dhim et l. (2012) hve shown differences etween the phytotoxic ctivity of six sunflower hyrids nd their residues effects on succeeding weeds nd crops. It hs to e noted tht in oth yers of their study, PR64E83 ws consistently the hyrid tht resulted to lower fresh weight of ivy-leved speedwell (Veronic hederifoli L.). Tht indictes strong phytotoxic ction y mens of the crop residues of the specific hyrid nd this utotoxicity is proly mong the min resons for Emir. J. Food Agric Vol 28 Issue 2 2016 139
Tle 3: Yield nd yield components of the three sunflower hyrids during the two yers of experimenttion Yer Hyrid Grin yield (kg h 1 ) 1000 grin yield (g) Grin numer per hed Oil concentrtion (%) Oil yield (kg h 1 ) 2009 PR64E83 6680cd 72.32 1330.82 37.30 2380 Oleko 8210 77.71 1492.11 36.27 2960 PR63A90 7500c 61.70 1617.04 38.77 2950 2010 PR64E83 5820de 40.26c 832.07 36.27 2220c Oleko 5200e 42.46c 761.04 34.03c 1770c PR63A90 9910 40.38c 1545.19 30.50c 3020 Men vlues within the sme column followed y the sme letter(s) re not significntly different using LSD tests t P=0.05 Tle 4: Profile of fts (% of min ftty cids) of the three sunflower hyrids during the two yers of experimenttion Yer Hyrid Percentge of ftty cids Sturted Monounsturted Polyunsturted Plmitic Stetic Elic cis Linelic cis 2009 PR64E83 20.03 60.14 19.82 11.79 5.9 58.25 19.72 Oleko 8.89c 86.67 4.44c 4.57d 3.02 86.07 4.34c PR63A90 18.85 64.83 16.33 11.55 4.82 62.93 16.2 2010 PR64E83 10.85c 41.77c 47.38 6.69c 3.25 40.32 47.2 Oleko 8.88c 83.81 7.31c 5.08cd 2.88 82.19 7.22c PR63A90 12.14 43.34c 44.53 7.69 3.32 41.69c 44.36 Men vlues within the sme column followed y the sme letter(s) re not significntly different using LSD tests t P=0.05 the significntly lower grin yield of PR64E83 in 2010, s shown in Tle 3. This could e lso true for Oleko, ut not for PR63A90. The numer of grins for PR63A90 ws higher during 2010 (resulting to high grin yield), proly ecuse of lower phytotoxic ction of the residues of this specific hyrid, comined with the higher rinfll during June 2010 compred with the previous yer (period of seed formultion). Oil content of sunflower is known to e ffected y the hyrid nd the temperture during seed development (Cnvin, 1965; Skoric, 1992). According to Roertson et l. (1971), high oleic hyrids hve usully oil content of 32.2-44.3%, while the corresponding vlues for conventionlly hyrids were 23.4-33.4%. In our study, the high concentrtion of elic cid in Oleko is rther nticipted (Skoric, 1992), however, the high concentrtion in 63A90 ws proly due to cross pollintion nd the insects previously visited the high oleic hyrid (Tle 4). Genotype is considered s the min fctor tht determines the oleic cid concentrtion s previously suggested y Fernndez et l. (1989) nd Izquierdo et l. (2002), however, cross pollintion y honeyees cn ffect the grin yield nd oil content (Nderitu et l., 2008). Moreover, the high tempertures during grin filling until mturity my hve lso plyed n importnt role to the high vlues oserved (Roertson et l., 1971; Anderson et l., 1978; Hzel et l., 1978). Our study lso reveled some significnt correltions mong the severl growth nd yield prmeters of sunflower. For 2009, LAI ws strongly correlted with grin nd oil yield (r=0.98 nd 0.94, respectively). This oservtion is in full ccordnce with previous studies (Mirlles et l., 1997; Dhim et l., 2012). Moreover, dry weight of sunflower plnts ws positively correlted with grin nd oil yield (r=0.95 nd 0.86, respectively). This finding is in greements with results of previous studies (Zffroni nd Schneiter, 1991; Mirlles et l., 1997). In ddition, dry weight of inflorescences is positively nd significntly correlted with dry weight of stems nd numer of grins (0.84 nd 0.79, respectively). Among the severl yield prmeters, grin numer ws found to e the one strongly correlted with the finl grin yield (r=0.92), finding tht is in full ccordnce with previous studies, indicting the mjor importnce of this chrcteristic for finl yields (Zffroni nd Schneiter, 1991). It hs lso to e noted tht there ws not ny significnt correltion etween numer of grins nd weight of 1000 grins (r=0.49, ns). CONCLUSIONS The results of the present study indicted tht the growth nd yield of sunflower hyrids might hve sustntil rnge nd should e certinly tken into ccount for the crop estlishment in ech region. Similr studies should e continued including more sunflower hyrids, soil nd climtic conditions. The ility of some hyrids such s PR63A90, even without eing high-oleic, to keep high grin nd oil yield even in the second yer of their cultivtion in the sme field is certinly very desirle trit nd it should e further studied. On the other hnd, hyrids such s Oleko seem idel for high grin nd oil yield (with high concentrtion of monounsturted ftty cids), however they fit etter to crop rottion, proly due to high phytotoxicity of the residues (exctly s in the cse of PR64E83). Our results highlight the underestimted importnce of sunflower hyrid selection for successful 140 Emir. J. Food Agric Vol 28 Issue 2 2016
estlishment of the crop nd the overll grin nd oil productivity. This is importnt, especilly in griculturl situtions nd regions where crop rottion is not common or widely dopted y the frmers. ACKNOWLEDGEMENTS Authors would like to thnk Filio Moustferi, Christos Christkis, Evgenios Agthokleous nd Kyrikos Christou for their invlule help with field nd experimentl ctivities. Author s contriutions The contriution of ll uthors ws equl in this study. REFERENCES Ali, Q., M. Ashrf nd F. Anwr. 2009. Physico-chemicl ttriutes of seed oil from drought stressed sunflower (Helinthus nnuus L.) plnts. Grss y Aceites. 60: 475-481. Anderson, W., R. Smith nd J. Mc Willim. 1978. A system pproch to the dpttion of sunflower to new environments. I. Phenology nd environment. Field Crops Res. 1: 142-152. Anjum, T. nd R. Bjw. 2005. A ioctive nnuionone from sunflower leves. Phytochemistry. 66(16): 1919-1921. Antolin, G., F. V. Tinut, Y. Briceño, V. Cstño, C. Perez nd A. I. Rmirez. 2002. 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