Effect of trees on yield, water expense efficiency and nutrient uptake by clusterbean in arid environment

The effect of Prosopis cineraria and Acacia albida planted at three spacings (5×5, 5×10 and 10×10 m) on availability of nutrients and moisture, and yield of clusterbean in arid environment was evaluated on a loamy sand soil. Available N, P and K in soil were considerably higher under the trees than that of the bare field. The soil under P. cineraria was richer in nutrients (N, P and K) and also maintained higher available moisture regimes as compared to the soil under A. albida. Nutrient uptake by the crop (grain + straw) differed both with the tree species as well as with their spacing. Nutrient uptake increased with decrease in the density of trees. The uptake of nutrients was in the order: sole crop>P. cineraria>A. albida. The water expense efficiency (WEE) was generally higher under P. cineraria than A. albida at comparable spacing. The crop yields, in general, were in the order: sole crop>P. cineraria>A. albida. Increase in the tree spacing increased the yield and WEE of clusterbean. The water expense efficiency under 10x10 m spacing of trees was more than the sole crop.