INHERITANCE OF RUST RESISTANCE IN LENTIL

Abstract

Seven pure breeding lines of microsperma (Dwarf I, ILL 6824, L 259, L 830, SKL 259 and EC 158867) and macrosperma (Precoz) lentils were tested in glasshouse for their reaction to rust (Uromyces fabae f. sp. lenUs). Only the macrosperma genotype Precoz was found to be resistant. All microsperma genotypes showed susceptible reaction. The cv. Precoz was crossed with six susceptible lines. The Fl and F2 generations of these crosses along with parental genotypes were also grown in glasshouse. Spore suspension of lentil rust was sprayed periodically on the plants. Temperature and humidity conditions in the glasshouse were kept congenial for heavy incidence of lentil rust. The disease reaction was observed by classifying all the disease-free plants as resistant and those with varying degree of fungal growth as susceptible. In all crosses, resistance was dominant in the F1 generation (Table 1). The pattern of F2 segregation in the six crosses revealed resistance to be controlled by duplicate dominant genes in Precoz (15 resistant: 1 susceptible).