Optimization of mature embryo based regeneration and genetic transformation of Turkish wheat cultivars


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye

Tezin Onay Tarihi: 2010

Öğrenci: ABDULHAMİT BATTAL

Danışman: HÜSEYİN AVNİ ÖKTEM

Özet:

The objective of this study was to optimize tissue culture, transformation and regeneration parameters of mature embryo based culture of Triticum durum cv. Mirzabey 2000 and Triticum aestivum cv. Yüreğir 89. The effects of auxin type of hormone at different concentrations and dark incubation periods on regeneration capacity were evaluated. Two different hormone types 2,4- dichlorophenoxyacetic acid and picloram were used at three different concentrations 2, 4 and 8 mg/l. Mature embryo derived calli were incubated in 6 different induction media at dark for 4 and 6 weeks for initiation of primary callus induction. After dark incubation periods, average callus fresh weight and primary callus induction rate were determined. The primary callus induction rates for 4 weeks and 6 weeks old dark adapted Mirzabey calli incubated was found to be 91 % and 93.25 % respectively. Yüreğir primary callus induction rate was 92.5 % for 6 weeks old calli in 6W2D medium and 86.75 % for 4 weeks old calli in 4W8P medium. The primary calli were transferred to embryogenic callus induction medium. The embryogenic callus formation was 94.88 in 6W2D medium for Mirzabey cultivar. The necrosis was observed at high concentration of 2,4-D for both of cultivars. After embryogenic callus induction, embryogenic calli were transferred into hormone free regeneration medium. The maximum regeneration rate (62.31 %) and culture efficiency (44.13 %) were observed in 4W2D medium for Mirzabey. However, the low regeneration rate was observed for Yüreğir (5 %) in 6W2D medium. The transformation studies were performed by using Obitek Biolab Gene Transfer System. The old and the modified loading units were used for optimization of bombardment pressure and distance for mature embryo based calli transformation. After bombardment of pAHC25 coated gold particles, histochemical GUS assay was performed and blue spots were counted. The transformation efficiency increased to 0.65 fold for 30 bar bombardment pressure and 5.5 fold for 35 bar bombardment by the modified loading unit. The modified loading unit could be used for further transformation studies.