DEVELOPMENT OF INITIAL MATERIAL FOR BREED ING OF HYBRID RYE IN RUSSIA

The results of long-term (1967 - 1993) studies on production of initia l material for breeding of hybrid rye are reviewed. Sterile forms isol ated from 45 varieties of winter diploid rye were genetically classifi ed by the criterion of P or R type of cytoplasmic male sterility (CMS) . Several genetic systems of CMS with cytoplasms of R or P type were p roduced and tested for use in breeding of hybrid rye. The combinationa l ability of 500 varieties, strains, and lines of winter rye was analy zed. Highly heterotic hybrids of winter rye with yields of up to 10000 kg of grain per ha were obtained on the basis of CMS. The frequency a nd level of heterosis in different types of rye hybrids and the ecolog ical and genetic variation of this effect in rye were analyzed.