Growth and yield of sorghum or cowpea in an agrisilviculture system in semiarid India

This study was conducted near Hyderabad, India during 1991-1994 to quantify the effects of shoot pruning, fertilization, and root barriers around Leuc aena leucocephala trees on intercropped sorghum (Sorghum bicolor) or cowpea (Vigna unguiculata) crop production under rainfed conditions. Crop plants grown with pruned trees attained higher dry matter and leaf area index than did those with unpruned trees. Two-year mean grain yields of sorghum with no root barriers were 76% and 39% of pure crop yield (1553 kg ha(-1)) for p runed and unpruned trees, respectively. Corresponding values for cowpea wer e 49% and 26% of pure crop yield (1075 kg ha(-1)). Sorghum or cowpea interc ropped with trees responded to fertilizer application more strongly than di d their respective pure crops, suggesting an increased need for fertilizer application in this agrisilviculture system over that currently used for pu re crops. Impact of root barriers was small on either crop. Irrespective of root barriers, a high response to tree pruning suggested above ground comp etition for light dominated tree/crop interactions in this agrisilviculture system.