Genetic variability for induced thermo tolerance in groundnut (Arachis hypogaea L.) germplasm

Abstract

High temperature is a major constraint to crop adaptation and productivity in groundnut especially when coincides with moisture stress. In the present study, thirty nine groundnut germplasm comprising of interspecific derivatives, advanced breeding lines, mutants and released cultivars were evaluated for their thermo tolerance at seedling stage in the laboratory under induced temperature treatment. Highly significant differences were observed among temperature treatments, genotypes and genotype x temperature interactions indicating differential response of genotypes to temperature treatment. High heritability coupled with high genetic advance over mean under induced temperature treatment revealed better scope for selection in the germplasm under induced temperature. Foliar disease resistant mutant (Mutant 110) and several advanced breeding lines (R 9214, ICGV 96266, ICGV 96262, ICGV 93020, ICGV 91177, ICGV 87264 and NC Ac 343) and three released cultivars (K 134, TMV 2 and Dh 40) have shown very less reduction (<30%) under induced temperature treatment indicating their seedling thermo-tolerance. These genotypes need to be assessed for their temperature tolerance under field conditions at different stages of crop growth.

Keywords

• groundnut
• induced temperature
• thermo tolerance
• interspecific derivatives