INHERITANCE OF LATE LEAFSPOT RESISTANCE IN GROUNDNUT MUTANTS

Abstract

The mutant VL 1-45 resistant to late leafspot, and its susceptible parent (VL 1) and grand parent (DER) were crossed in three combinations viz., VL 1-45 x VL 1, VL 1-45 x DER and VL 1 x DER. All the hybrids (Fl'S) showed intermediate values for disease resistance, which skewed towards the susceptible parents indicating the partial dominance of the gene(s) causing susceptibility. Segregation in the F2 revealed the presence of a suppressor element (inhibitory) in the original DER parent which was subsequently eliminated by a mutational event and that duplicate complementary recessive genes controlled the late leafspot resistance in the crosses studied. The genotypic constitutions of the parents based on the genetic hypotheses were formulated. Further, there is a need to test for allelism with other known resistant genotypes.