Effect of Varieties, Planting Densities and Phosphorus Levels on Seed Yield and Post-Harvest Soil Physico-Chemical Properties of Rice Fallow Redgram

Aim: To assess the effect of varieties, planting densities and phosphorus levels on yield and physico-chemical properties of post -harvest soil in rice fallow redgram. Study Design: The experiment was laid out in strip-split plot design with three varieties as vertical factor viz., V1: ICPV-21333, V2: ICPV-21444 and V3: ICPV-; two levels of spacings viz., P1: 0 kg P2O5 ha-1, P2: 25 kg P2O5 ha-1, P3: 37.5 kg P2O5 ha-1 and P4: 50 kg P2O5 ha-1. Place and Duration of Study: RL 12, block 3 and 4, International Crops Research Institute for Semi-Arid Tropics (ICRISAT), Patancheru, Hyderabad, during rabi, 2022-23 and 2023-24. Methodology: The investigation consisted of three varieties as vertical factor, two levels of spacing as horizontal factor and four levels of phosphorus as sub-plots with a total of 24 treatment combinations and replicated thrice. Data recorded on various parameters was subjected to scrutiny by ANOVA technique for split plot design concept. Data was subjected to analysis of variance procedures as outlined for strip-split plot design. Results: From this investigation, it was found that seed yield was significantly higher with the variety ICPV-21333 (812 and 750 kg ha-1), but remained statistically comparable to ICPV-21444. Among the spacings, it was highest with 30 cm x 10 cm (792 and 740 kg ha-1) and with respect to phosphorus levels, crop fertilized with 50 kg P2O5 ha-1 registered higher seed yield (797 and 740 kg ha-1) but, was statistically at par with 37.5 kg P2O5 ha-1. Available post- harvest soil N, and K2O was not influenced by the various treatments, but available P2O5 was significantly influenced by phosphorus levels. Higher available P2O5 was observed with the application of 50 and 37.5 kg P2O5 ha-1 kg P2O5 ha-1, while the lowest status was noticed with 0 kg P2O5 ha-1. Similarly, bulk density, pH, EC and OC were not significantly influenced by varieties, spacings and phosphorus levels and due to their interaction during both the years of study.