evaluation of allelopathic effects of fenugreek extract on germination and growth of some crop and weed species

abstract in order to study the effect of different organ extracts of fenugreek (trigonella gracum (on germination of some crops and weeds, an experiment was conducted in completely randomized design with 3 replications. factors included 4 species soybean (glysin max),sesame ( sesamus indicum) , pigweed (amaranthus retroflexus) and velvetleaf (abotilon teophrasti) and the extract of different fenugreek organs (leaf, stem, seed, pod and total organs( in 4 levels (check, 4, 8, 32 and 64 g powder/1000 ml distilled water). results indicated that plants had different reaction to concentrations of different organ extracts. in the all studied species, negative and significant correlation was obtained between different concentrations of extract and germination percentage. also,with increasing extract concentration of fenugreek, germination rate decreased in the studied crops and weed. nagative and significant correlation was observed between germination percent and different concentrations of organs and minimum of regression slope was obtained in stem extract. root and shoot length had negative and significant correlation with extract concentrations, in total species, except of soybean. in general, velvetleaf had the most sensivity for fenugreek allelochemical.