Bazı arpa çeşitlerinde ve yabani arpa (Hordeum spontaneum Kosh.)'da soğuğa uyumda etkili genlerin araştırılması
Özet
In order to identify the different components of stress adaptation capacity and their role in cereals, evaluation of the cellular physiological reactions of 11 Turkish barley genotypes as leaf water potential (MPa) changes against cold stress conditions (+4 °C) was performed in cold applied and control plants by pressure bomb PMS instrument for 10 consecutive days on 5-weeks-old plants. Based on the results of analysis by MSTAT-C software, genotype, cold stress, time (day) and interactions were significant (P<0.01). Leaf water potential of cold stress plants (-0.68 MPa) significantly differed from control (-0.53 MPa). Investigation of the transcript changes of HvCBF1, CBF9, COR14b, DHN8 cold- responsive genes with the GAPDH control gene in 11 barley varieties and 2 wild genotypes in control and cold treated plants by real time quantitative PCR revealed that the amount of HvCBF1 gene expression controls the variation in leaf water potential in this plant so that, the plants with the lowest water potential loss showed the highest expression level of this gene among the studied genotypes and vice versa. These results indicate that this gene can be candidate for enhancing cold and water stress tolerance in cereals. In order to improve T-DNA transfer potential in barley, we re-evaluated and optimized some factors which are related to in vitro regeneration, explant treatment and co-culture period. For this purpose, zygotic embryos in Özen genotype (control embryos and embryos treated with cold (+4 °C) for 24 hours on MS medium) were treated with Agrobacterium tumefaciens GV 2260 strain harboring p35 GUS-INT plasmid followed by co-cultivation for 24 and 48 hours and as a result, the highest transformed events were obtained in the explants subjected to 24 hours cold treatment followed by co-cultivation for 48 hours.