Nohut (Cicer arietinum L.) çeşitlerinde kuraklığa bağlı oksidatif stresin fizyolojik ve biyokimyasal parametrelerle belirlenmesi

Bu calismanin amaci; Turkiye’de yaygin olarak yetistirilen nohut cesitleri arasinda kurakligadayanikli olanlarin, seleksiyon kriteri olarak kullanilan bazi fizyolojik ve biyokimyasalparametrelerle belirlenmesidir. Bu amacla, 2007 ve 2008 yillarinda, iki sera denemesi ve ikitarla denemesi sulanan ve sulanmayan kosullarda yurutulmustur.Kurakliga dayanikli cesitlerin seciminde; verim ve verim ogeleri ile kuraklik hassasiyet indeksi(KHI), yaprak su tutma kapasitesi, yaprak nispi nem icerigi, nispi klorofil, membrangecirgenligi, prolin birikimi, H2O2 birikimi, lipid peroksidasyonu, bitki ortusu sicakligi,enzimatik olmayan antioksidanlar ve antioksidan enzimlerden superoksit dismutaz (SOD; EC1.15.1.1), katalaz (KAT; EC 1.11.1.6), askorbat peroksidaz (AP; EC 1.1.1.11) enzim aktivitelerigibi parametreler incelenmistir.Bu calismada yer alan 11 nohut cesidinin (Menemen-92, Akcin, Aydin-92, Izmir-92, Kusmen,Canitez-87, Gokce, Sari, Uzunlu-99, Er-99 ve ILC-195) kuraklik stresine farkli tepkilergosterdikleri belirlenmistir. Nohut cesitlerinin KHI’lerine gore bir degerlendirme yapildiginda,sera ve tarla kosullari ile yillar arasinda onemli farkliliklarin oldugu ortaya cikmistir Serakosullarinda cesitlerin NNI’leri kurakliga bagli olarak azalmis, YSTK’leri ise 2007’de artmis2008 de ise azalmistir. Tarla kosullarinda ise NNI ve YSTK bazi cesitlerde artar ikenbazilarinda azalmistir. Sera kosullarinda toplam klorofil, tarla kosullarinda nispi klorofil cesitlerarasinda farkliliklar gostererek kurakliga bagli azalma gostermistir. Kuru kosullarda yetistirilennohut cesitlerinin bitki ortusu sicakliginin (BOS), sulu kosullarda yetistirilen cesitlerinBOS’indan daha yuksek degerlere sahip oldugu belirlenmistir. Butun nohut cesitlerinde kuraklikstresine bagli olarak H2O2 birikimi ve buna bagli olarak lipid peroksidasyonunda artisgerceklesmistir. Calismamizda kurakliga bagli olarak butun cesitlerin dokularinda prolinbirikimi ve enzimatik olmayan antioksidanlarin miktarinda artis gorulmustur. Kurakliga bagliolarak enzimatik antioksidanlardan SOD azalirken, KAT ve AP artis gostermistir. Bu calismasonucunda, sera ve tarla kosullarinda Gokce, Sari ve Uzunlu-99 cesitlerinin diger cesitlere gorekurakliga toleransinin yuksek oldugu belirlenmistir.Abstract  The main objective of this study was to determinate with some physiological and biochemicalparameters usable as selection criteria between chickpea genotypes that grown in Turkey. Forthis purpose in controlled conditions two greenhouse experiments in 2007 and 2008 and also inAnkara-Haymana conditions two consecutive field experiments were performed under droughtand irrigated conditions.The parameters studied on irrigated and rainfed (drought) conditions were yield, yieldcomponents, canopy drought susceptibility index, leaf water retention capacity (LWRC),relative water content (RWC), relative chlorophyll, membrane permeabilty, proline and H2O2accumulation, lipid peroxidation, canopy temperature, non enzymatic antioxidants and activitiesof antioxidant enzymes (superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC1.11.1.6), ascorbate peroxidase (APX; EC 1.1.1.11))The 11 chickpea cultivars (Menemen-92, Akcin, Aydin-92, Izmir-92, Kusmen, Canitez-87,Gokce, Sari, Uzunlu-99, Er-99 ve ILC-195) used in this study showed great variations inresponse to drougt stress. When drought susceptibility index of the cultivars was considered,there was a great differences between greenhouse and field conditions and also between years.Under greenhouse conditions, RWC of the cultivars decreased for both years while LWRCincreased in 2007 and decreased in 2008. Under field conditions, both RWC ve LWRCincreased or decreased depending on cultivars by drought stress. Total chlorophyll concentrationin greenhouse and relative chlorophyll measurements in field conditions were decreased bydrought stress. In contrast to chlorophyll, the canopy temperature of the cultivars increased bydrought stress. Drought stress caused to increase H2O2 ve prolin accumulatin in chickpeancultivars. As the consequence of H2O2 increase, lipid peroxidation (MDA content) alsoinceased. The activity of SOD decreased while CAT, APX and non enzymatic antioxidantsincreased by drought stress. According to results, for both field and greenhouse conditions cvs.Gokce, Sari and Uzunlu-99 are recorded as drought tolerant.