Allelopathy Journal

Laboratory bioassays and pot culture experiments were conducted to assess the allelopathic influence of leaf leachates of multipurpose trees (Artocarpus heterophyllus, Mangifera indica, Ailanthus triphysa, Anacardium occidentale, Tamarindus indica, Tectona grandis, Thespesia populnea, Casuarina equisetifolia, Gliricidia sepium, Strychnos nux-vomica) planted in the multi-storey home gardens of Kerala, on vegetables crops (cowpea, bitter gourd and brinjal). The nature and degree of allelopathic effects of trees varied with crop species. Tamarind, teak, Casuarina and Strychnos caused severe allelopathic inhibition of cowpea, hence were incompatible. Gliricidia, portia, tamarind, teak and cashew were incompatible with brinjal. The Ailanthus, cashew, strychnos, mango, portia, tamarind and teak were detrimental to bitter gourd. The inhibitory effects were most prominent in brinjal than cowpea and bitter gourd and were not overcome with dilution. The results will help in differential selection of vegetables, for combining with trees in agroforestry systems.