INTROGRESSION OF DIVERSE GENES FOR RESISTANCE TO RUSTS INTO AN IMPROVED WHEAT VARIETY, KALYANSONA

Breeding for resistance to the three rusts of wheat usually requires i ncorporation of genetically independent factors conferring resistance to each rust. Linked resistance genes in some alien translocation stoc ks permit concurrent transference of resistance for more than one rust . Alien derived resistances, however, are often reported to be associa ted with reduced yield and other undesirable characters. In our experi ence, backcross breeding when given a limited number of backcrosses (3 -6) and with suitable selection procedures has resulted in lines givin g yields higher or comparable to the recurrent wheat parent Kalyansona and resistance to one, two or all three rusts without any adverse eff ects. Some of the rust resistant derivatives also show resistance to N eovossia indica (Karnal bunt). The derivatives thus developed when use d as parents in a breeding programme have produced several improved cu ltivars with high yields, superior grains and diversity for resistance to rust pathogens. One of the cultivars, named 'Vaishali' (DL784-3), has been officially released for cultivation in the country.