Response of chickpea cultivars to phosphorus application

Low soil P levels pose major limitation in realizing optimal growth and development of grain legumes and yet the suitable P levels of common chickpea cultivars (i.e. Black gram and Benazir) are not on the record. Effect of various P application levels (0, 25, 50 and 75 kg P2O5 ha(-1)) on two chickpea cultivars was evaluated in a field study using randomized complete block design. All the treatments received recommended dose of N and K2O (each at 30 kg ha(-1)) in the form of urea and SOP, respectively. Application of P resulted in significant increase in plant height (102.4 cm), number of branches (31.1 plant(-1)) and grain yield (1058 kg ha(-1)), shoot P (0.49%), P uptake (5.18 kg ha(-1)) and protein content (17.4%) over control. Increasing the P levels from 50 to 75 kg P2O5 ha(-1) did not have any significant effect on number of branches (30.4 to 31.1 plant(-1)). As for cultivars, a significant effect was observed for grain yield (p < 0.06) and P uptake (p < 0.001) and the differences were prominent when the P level was increased from 50 to 75 kg P2O5 ha(-1). The P in shoot (0.50%) and plant uptake (5.71 kg ha(-1)) were significantly affected by the interaction between P fertilizer and the cultivars in Benazir at the P level of 75 kg P2O5 ha(-1). The shoot P content gave a positive relationship with grain yield (R-2 0.67) and protein content (R-2 0.73) and grain yield with P uptake (R-2 0.89). Growth, yield, shoot P, P uptake and protein content of chickpea cultivars enhanced with phosphorus levels with highest at 75 kg P2O5 ha(-1). Chickpea cultivar Benazir responded better with regard to grain yield and P uptake.