Assessment of genetic variation and selection of most responsive lines for root traits in relation to phosphorous nutrition in groundnut (Arachis hypogaea L.)

Genetic studies were conducted to select lines efficient in Phosphorus (P) uptake under the soils with reduced P availability from a set of RILs derived from a cross JL24 x ICGV 86590 in groundnut. ANOVA and genetic variability components revealed significant variations among RILs, phosphorus levels and their interaction for most of the root traits enabling intensive selection. ICGV 86590 showed a higher response to P, while JL 24 recorded negative response for primary root length and shoot length. RILs displayed variable degree of response (in percent). Selected 20 contrasting lines exhibited significant variations with high heritability for P uptake. In both P availability conditions P uptake traits showed significant positive correlation with biomass traits. RILs 1–23 and 1–18 were most responsive based on their per se performance and per cent responsiveness over the traits.