Allelopathic effects of some promising agro forestrytree species on different annual crops

An experiment was conducted at ICAR RCER, RC, Ranchi, India during 2012-13 to assess the potential allelopathic effect of leaf extract of eleven tree species [Mango (Mangifera indica), Poplar (Populus deltoides),Arjun (Terminalia arjuna), Palas (Butea monosperma), Bakaine (Melia azedarach), Acacia mangium, Acacia auriculiformis, Bael (Aegle marmelos), Teak (Tectona grandis), Jackfruit (Artocarpus heterophyllus), Shisham (Dalbergia sissoo)] on nine annual crops (black gram, gram, pea, sponge gourd, mustard, okra, brinjal, chilli, tomato). Data were recorded on seed germination (after 10 days of seed sowing) and growth and biochemical composition of 20 days old seedlings. Reduction in germination % of annual crops was recorded with application of leaf leachate of each tree species except D. sissoo, A. heterophyllus, A. marmelos and A. mangium. With respect to weight of whole plant, application of leaf extract of M. indica, B. monosperma, A. mangium, A. auriculiformis and A. marmelos resulted in significant increase in total fresh and dry weight over that of control whereas none of the treatments resulted in significant reduction in fresh weight of annual crops. Among the annual crops, reduction in total fresh weight of the plant than that of control was recorded in case of bottle gourd whereas significant increase in fresh weight due to application of leaf extract was recorded in case of black gram, gram, okra and brinjal. Application of leaf extract of M. indica, A. mangium, A. auriculiformis and A. marmelos resulted in significant decrease in total chlorophyll content over that of control. Hence, the study clearly indicated beneficial effect of leaf extract of Mangifera indica, Butea monosperma,Acacia mangium, Acacia auriculiformis and Aegle marmelos with respect to plant growth of annual crops.