Disease Reaction and Seed Yield Stability of Advanced Lentil Genotypes in Bale Highlands

Abstract

Twelve lentil genotypes were evaluated for their reaction to diseases (rust and Ascochyta blight) and seed yield stability together with two commercial varieties (Chalew and Ada'a) and the local cultivar (Bale), at Sinana, Lower Dinsho and Agarfa in Bale Zone of Oromiya Region during the 'bona' crop season (July-December) from 1999 to 2001. All the genotypes and varieties showed resistant reaction to rust and resistant-to-moderately-susceptible reaction to Ascochyta blight. Whereas, the local cultivar was susceptible to rust and moderately susceptible to Ascochyta blight. There was highly significant variation among environments (E) and genotypes (G) in seed yield. G x E interaction was also highly significant. Eight of the genotypes and Ada’a were stable in seed yield over environments. There was significant (p < 0.01) negative association of seed yield with rust (r-0.739) and Ascochyta blight (r-0.642)
severity. There was also strong and highly significant linear association between yield stability parameters and disease reaction. This indicated that variation of disease severity over different environments on a particular genotype/variety might be one of the major factors for seed yield instability.