INHERITANCE OF RESISTANCE TO WHITE RUST DISEASE IN INDIAN MUSTARD

Abstract

A complete diallel set of crosses was produced from ten diverse parents of varying degrees of resistance and susceptibility to white rust and assessed to study the inheritance of the disease caused by Albugo candida. Data from parents and their FIS including reciprocals were analysed using Griffing and Jinks- Hayman methods of diallel analysis. The experiments confirmed from the analysis of both the approaches that additive gene action predominantly controlled the inheritance of white rust disease. The parent Poorbijaya was the best general combiner followed by BJ-38. The cross Glossy mutant x BJ-38 was found to be the best specific combination. All the crosses showing superior sca effects could be utilised for getting transgressive segregates with better resistance to white rust in mustard. The mean degree of dominance was partial. Heritability estimates in narrow and broad senses were high. Predominance of additive' genetic variance coupled with high heritability suggested that simple selection procedures such as pedigree breeding would be useful for improving the level of resistance.