Screening and selection of P-efficient groundnut genotypes for calcareous soils in India

Abstract

The groundnut (Arachis hypogeae L.), in India, is mainly grown on light textured and calcareous soils deficient in available P where response of P is not consistent causing prominent P deficiency. Identification and use of phosphorus efficient groundnut genotypes is the best alternative for which insitu field screening was conducted in calcareous soil with 5-6 ppm available phosphorus. Seventy groundnut genotypes were grown in the field under low (unfertilized control) and high (fertilized with 50 kg P ha-1) P conditions, the growth, yield and utrient concentrations and uptake by groundnut were studied and the genotypes having superior yield responses and high P uptake, both at low and high levels of P availabilities, were selected as P-efficient. High P concentration in leaves during early growth stages and high P uptake at harvest was observed in the P-efficient genotypes. On an average, the P-efficient genotypes showed 275 g m-2 pod yield, however, the P-inefficient genotypes showed 102 g pod m-2 . Based on four years of study, the genotypes GG 5, FeESG 8, FeESG 10, NRCG 1308, NRCG 3498, and SP 250A were identified as P-efficient and genotypes VRI 3, B 95, NRCG 162, PBS 16003, 20012 as P-inefficient. These P-efficient groundnut genotypes which performed well with relatively high yields both under low and sufficient P conditions are being recommended for their cultivation in low P soils, to avoid any yield losses due to P-deficiency.