Progress in Manipulation of Genetic Systems Regulating Flowering Response in Wheat

Abstract

Two dominant Vrn genes were introduced into background of winter type durum wheat Kristall 2. Those congenic lines were used for genotype identification (almost all cultivars carried Yrn-A1), creation of later durum for extra-early sowing in spring, and for broadening winter durum gene pool by selection of winter segregants from spring x spring crosses. Combining various dominant Vm and Ppd genes was achieved in the background of Mironovskaya 808; it showed some additive effects for developmental acceleration. The effects of various Ppd genes were studied in congenic lines. They coincided potentially with the ontogenetic rate; however, the realization of that potential was strongly dependeat on stresses existing at specific ontogenetic stages. Those lines were used for Ppd genotype identification of 21 winter type cultivars. And they were involved in test-cross for allelism with analogous lines from John Innes Centre. Congenic Mironovskaya 808 lines were developed on two loci controlling differences in duration of vernalization response. Analogous lines are being produced on the alien introgressed Vrn genes which are non-allelic to the known ones in bread wheat. The differences in earliness per se need more extensive studies.