Department of Forestry, Post Box. 59, H.N.B. Garhwal University, Srinagar - 246 179, Uttaranchal, India.
Allelopathy Journal 15: 285–294, (2005).
Phytotoxic effects of leaf and bark extract of agroforestry tree spp. (Grewia oppositifolia, Ficus roxburghii, Celtis australis and Boehmeria rugulosa) from three altitudes (950, 1350, 1550 m) were investigated on germination and growth of foods crops (Triticum aestivum, Hordeum vulgare and Brassica campestris). Leaf and bark extracts equally inhibited the germination and growth of test crops. Grewia oppositifolia extracts greatly suppressed the radicle elongation, while, Ficus roxburghii extracts were most toxic to germination of test crops. Brassica campestris was most resistance to tree extracts than Triticum aestivum and Hordeum vulgare, while, Triticum aestivum was most sensitive. The leaf and bark extracts of trees from lower altitude (950 m asl) prepared in cold water were more toxic, however, leaf and bark extracts from higher altitudes prepared in hot water had identical effects. The importance of these agroforestry trees species decreases in order of: B. rugulosa > C. australis > F. roxburghii > G.oppositifolia. Amongtrees, G. oppositifolia was found most allelopathic, while among the field crops, the most resistant was mustard and most susceptible was barley, while, wheat was moderately resistant.
