Abstract
Heavy doses of synthetic weed control chemicals have facilitated herbicide resistance in weeds as well as predicted to possess toxicities. Natural compounds can be screened as potential herbicides which are more cost effective, efficacious, selective and environmentally safe. Experiments were conducted on selected weeds (Rumex dentatus, Euphorbia helioscopia, Chenopodium album, Avena fatua, Phalaris minor) to study allelopathic potential of Rhazya stricta. Experiments were performed using a medium of 0.75 % (w / v) agar, filter paper and soil. Parameters studied for assessing allelopathic effects were germination inhibition (%) along reduction in radicle and plumule length (cm). Results showed that seed germination of R. dentatus, P. minor and C. album is inhibited by R. stricta allelochemicals. Minimum germination for C. album was noted whereas non significant effect on the germination of E. helioscopia, T. aestivum and A. fatua was observed. Leaf extract of R. stricta on the agar, filter paper, and the soil inhibited the radicle and plumule length (cm) of all the test species. Results have indicated that even though radicle length and germination of T. aestivum is not affected by leaf extract of R. stricta, the plumule length was substantially decreased. The retarding effect of growth on wheat seedlings indicates that R. stricta might not be an acceptable candidate for weed control under field conditions.