5352
HAYAM FOUAD IBRAHIM SAYED
MOLECULAR GENETIC STUDIES ON SOME DROUGHT AND SALINITY TOLERANCE GENES IN BREAD WHEAT
wheat, triticum aestivum, drought and salinity stress, relative water content, cloning, agrobacterium, transformation.
The aims of this study were identifying of some wheat varieties and double haploid response to drought and salinity stress to determine and isolation of tolerant genes and select a gene for cloning it in tobacco plant. The behavior of seven wheat (triticum aestivum) genotypes under salinity and drought stress was studied. The genotypes used were double haploids (DH1, DH2, DH3 and DH4) and local verities (Sakha93, Sids1 and Gemmiza9) and relative water content (RWC) was estimated for the varieties and DH under drought stress 30% polyethylene glycol 6000, after 72 hours of treatment, The genotypes DH4 had the higher RWC (91.93%) while Sids1 had the lowest RWC of 68.23%. under water stress 30% PEG-6000. While, at salinity level 2.5% NaCl, DH3 displayed the highest relative water content (92.71%) and Gimmeza9 had the lowest RWC 75.88%. Using primers and polymerase chain reaction (PCR) technique, the genes WZY2, WUB3, ZFP22, TaOF1b, STRP and Di19a were detected in all genotypes and gave fragments with MW. 194,234,182,204,228 and 747bp respectively, with variance expression between different genotypes. Three genes were selected for study the expression of whole sequence genes. DH4 the highest RWC genotype under drought stress and DH3 was had the highest RWC genotype under salinity stress at different times 0, 3, 6,12,24,48 and 72h, in leaves and roots, The wzy2 gene appeared 474bp which varied in expression between leaves and roots, while STRP with 879bp appeared in DH4 in roots only at 48h, however in DH3 under salinity stress no gene expression was appeared. On the other hand, Di19a with 747bp appeared in DH3 at 24 and 48h under salinity stress. The three genes were isolated and the sequences of the genes were compared with genbank, wzy2 gene was selected and cloned by carried on pBi121 vector, propagated in E. coli and transformed in tobacco leaf disc mediated Agrobacterium by using tissue culture technique the callus, leaves and roots were obtained, the whole plant was transferred to adaptation. The transformed wzy2 gene was detected using PCR reactiontechnique by using primers compared with control.
2017
Ph.d
Cairo
Agriculture