ANALYSIS OF GENETIC PROFILES OF SPRING WH EAT CULTIVARS

Via the database of wheat genetic resources and programs of pedigree a nalysis GRIS 1.5, genetic profiles of 108 common spring wheat cultivar s zoned in the former USSR during the last 25 years [including cultiva rs produced in the commonwealth of Independent States (CIS)] were cons tructed. The dynamics of genetic diversity of cultivars over space and time were studied by cluster analysis of the genetic profiles. The st ability and genetic contributions of the set of primary ancestors were demonstrated in cultivars zoned during different periods. The composi tion and genetic contributions of the set of primary ancestors depende d on the region of breeding. Along with stability of the primary set o f ancestors over time, a significant increase in the gene pool of mode m cultivars was observed, caused by the involvement of new donors resi stant to unfavorable factors in the breeding process. It was concluded that genetic erosion or reduction in diversity of zoned cultivars did not occur during 25 years of breeding. On average, the genetic basis of cultivars zoned in the 1900s expanded three fold.