Effect of soil-moisture regime, seed rate and phosphorus fertilizer on water use, P uptake and economics of late-sown lentil (Lens culinaris) u. VENKATEsWARLu , 1. P. s. AHLAWAT

Abstract

A field experiment was conducted with late-sown lentil (Lens culinaris Medikus) during the winter seasons of 1984-85 and 1985-86 on a sandy-loam soil at New Delhi. Seasonal and daily consumptive use of water. water-use efficiency, total P uptake and net returns increased with increasing frequency of irrigation, being the maximum with irrigation at 0.60 irrigation water depth : cumulative pan evaporation (IW : CPE) ratio. Lower soil profile of 3&60 cm contributed the maximum mosihue in unirrigated plots, whereas soil profiles of 15-30 cm and (r15 cm contributed more moisture in irrigated plots during 1984-85 and 1985-86 respectively. Higher seed rate of 60 kgha recorded higher total and daily water use, water-use efficiency, P uptake and net returns than of 40 kg/ha. Lower soil profile of 30-60 cm contributed relatively more moishue in the case of 60 kg seedma. P application up to 35 kg PIO,/ha increased the total and daily water use, and that up to 70 kg P205 /ha increased the water-use efficiency P uptake and net returns. Phosphobacterial inoculation alone or with 35 kg P105/ha recorded higher water- use efficiency and net returns in both the seasons, and total P uptake during 1985-86 compared with no P and 35 kg P205 alone respectively.