Early generation intermating for yield improvement in groundnut (Arachis hypogaea L.)

Abstract

Seeds of 4 crosses of groundnut (Arachis hypogaea L.), 'Robut 33-1' x 'Chico', 'Robut 33-1' x 'NC Ac 17090', 'Robut 33-1' x 'PI 298115' and 'MK 374' x 'GAUG 1', were irradiated with 30 kR. In the F₁, some branches of each plant were intermated with other plants at random and others selfed in each cross to produce S₂ and F₂ seeds. They were evaluated for pod yield, shelling percentage and 100-kernel weight. The frequency of plants superior to F[in1] was much higher in S₂ than in F₂, which was, in general, true for the values of yield and its components. The S₂ and F₂ were advanced to third generation by selfing. The families descending from S₂ showed clear superiority over those from F₂. The reason for such superiority was suggested to be the recombination of genes from the upper and lower ends of the genotypic distribution under intermating.