Indian Agricultural Research Institute, Wheat Breeding Station, Simla
*Present address: Division of Genetics, I.A.R.I., New Delhi-12.
+Present address: Regional Research Centre (IARI), Pusa (Bihar).
One hundred and eighty-two varieties of wheat were studied against eight races of stripe rust. The results indicated that varieties having the genes Yr2, Yr6 and Yr7, either singly or in combination, were resistant when tested with individual races, showing thereby the effectiveness of these genes in conferring resistance against Indian races. A large number of other varieties with genes not yet identified exhibited complete resistance when tested individually against all the eight races. Six of these varieties may have the same genotype for resistance as that possessed by Webster. Similarly, E. 7216, Agra Local and N.P. 846 may have gene/genes similar to those present in Michigan Amber. Five varieties have shown identical pattern of infection when compared with Chinese 166 (Yr1). This suggested that these varieties may possess Yr1 gene. Similarly varieties E. 5557 and E. 8510 may have gene Yr5 (T. spelta album).
Pathological tests on 12 varieties indicated that 9 new genes may be involved in conferring resistance to eight Indian races of stripe rust. The use of these additional genotypes as differential hosts for the differentiation of stripe rust flora in India has been suggested.
Kharchia was found susceptible to all the eight races. The use of this variety for producing isogenic lines to be utilized in India for stripe rust has been suggested.
