Effect of phosphorus and biofertilizers on growth, yield and nutrient uptake of long duration pigeonpea under rainfed condition

Field experiments were conducted in Varanasi, Uttar Pradesh, India, during the 2004-05 and 2005-06 rainy seasons, to study the effect of phosphorus (P) fertilizer levels (0, 15, 30, 45 and 60 kg P2O5/ha) and biofertilizers (untreated control, Rhizobium, PSB and Rhizobium + PSB) on growth, yield and nutrient uptake of long duration pigeon pea. The results showed that the application of 60 kg P2O5/ha being at par with 45 kg P2O5/ha recorded the maximum plant height (203.0 cm), number of primary branches (20.8), dry matter per plant (159.6 g), grain yield (2260 kg/ha), stalk yield (8020 kg/ha) and uptake of N (112.3 kg/ha) and P (18.9 kg/ha). Among the biofertilizers, Rhizobium+PSB produced significantly taller plants (198.7 cm), maximum number of branches per plant (18.9), dry matter per plant (156.4 g), grain yield (2060 kg/ha), stalk yield (7560 kg/ha) and uptake of N (104.9 kg/ha) and P (16.9 kg/ha) than other biofertilizers treatments. The combined effect of 60 kg P + Rhizobium + PSB produced significantly higher dry matter (165.8 g/plant), grain yield (2510 kg/ha) and P uptake (21.4 kg/ha) than other combinations, except 45 kg P2O5 + Rhizobium + PSB. Maximum net returns (Rs. 40 005) was obtained with 60 kg P2O5 + Rhizobium + PSB, followed by 45 kg P2O5 + Rhizobium + PSB (Rs. 38 920)