Genetic variation for resistance to ergot (Claviceps purpurea [Fr.] Tul.) among full-sib families of five populations of winter rye (Secale cereale L.).

Ergot (Claviceps purpurea [Fr.] Tul.) is a serious disease of rye (Secale cereale L.) and it adversely affects the quality of grain. The present investigation was undertaken to study genotypic variability among full-sib families (FSF) of five open-pollinated (OP) winter rye populations of highly diverse origin, namely Dankovskie Selekcyine (Poland), Charkovskaja (Ukraine), NEM4 (Russia), Halo and Carokurz, both from Germany. About 50 FSF were developed at random in each population, and the FSF of each population were evaluated in separate but adjacent experiments conducted in four environments under artificial inoculation. A mixture of conidia of C. purpurea isolates was sprayed thrice during the flowering period. The materials were manually harvested at yellow-ripe stage. Resistance trait recorded was disease severity, i.e. percent ergot sclerotia in grain by weight. Mean ergot severity ranged from 2.29 to 4.08% for the five populations across environments. Significant genotypic variation (P < 0.01) due to FSF and FSF x environment interaction was observed within each population. Genotypic variation within all populations was higher than that among five populations. All populations showed high estimates of heritability (0.72-0.89). The study indicated that the evaluated OP populations are rich reservoirs of genetic variation that should also be used in hybrid breeding. Recurrent selection to further improve ergot resistance should be successful.