Investigation of the effects of Rht5 dwarfing gene on choleoptile length at agronomic and molecular level in wheat (Triticum aestivum L.).

The seeds of the lines at F3 generation of the cross between MarJ12 (Rht5) and Scholar bread wheat varieties (Triticum aestivum L.) were obtained from the USA. The F4 generation of the lines was cultivated in Bornova conditions during the 2014-2015 wheat production season. In this study, plant height, peduncle length, spike length, spikelet number per spike, grain number per spike, grain length, grain width, grain weight, coleoptile length, first leaf length and number of primordial roots were measured in these lines at the F4 generation and it was attempted to determine whether there was an association between plant height and coleoptile length and, if so, what the relationship was. The result of the screening of F4 generation lines of Marj12 x Scholar hybrid combination using Xbarc102 marker of the Rht5 gene showed that the 19 lines had mother band pattern, the 34 lines had father band pattern and the 12 lines had heterozygous band pattern. No band was observed in 7 individuals. The distribution of the Rht5 dwarfing gene in the F4 population was theoretically different from the expected. As a result of the statistical analyses, the significant differences were obtained among the control varieties and among the blocs for all traits except grain number per spike. Also, the statistical differences among the lines were observed for grain length, grain width and grain weight. According to the results of regression analysis, Rht5 gene explained 32% of phenotypic variation in plant height. As a conclusion, the lines that have medium or short plant height and also long coleoptile could be considered as promising genotypes in terms of transferring to next generations and using to obtain of the desired varieties.