Weed control using allelopathic plant species

Several laboratory experiments were conducted during the course of this project to \ntest the allelopathic effects of \nBrassica napus \nL. leaves, stems, \nroots and flowers on \nthree weed \nspecies \nPhalaris minor \n(Retz.), \nConvolvulus arvensis \n(L.) and \nSorghum \nhalepanses \n(L.) germination and growth, and to determine the glucosinolates profile \nand their concentration in \nBrassica napus \ntissues. \nIn this study, it was found that all water extract \ntreatments from different \nBrassica \nnapus \nparts and under different concentrations had the ability to inhibit weed \nspecies germination and growth significantly. Exposure to flower and stem extracts \ncaused \nthe \ngreatest reduction in the seed germination and seedling growth of all \nweed species that \nwere \ntested in this study. \nWater extracts from different \nBrassica napus \nparts and during different plant \ndevelopment stages significantly inhibited the seed germination and growth of all \nweed species. Glucosinolates profiles and concentrations in \nBrassica napus \ntissues \nwere \nsignificantly different between different plant parts during different plant \ndevelopment stages. \nProgoitrin was the dominant glucosinolate in \nB. \nnapus \nflowers \nand \ngluconasturtiin \nin roots. However, flower extracts \nwere \nmore effective \nin weed \nmanagement as compared with root extracts. \nApplying aqueous solution of pure glucosinolate significantly inhibit seed \ngermination and seedling growth. Glucos \ninolate types and their concentrations \nlinked positively with \nweed species inhibition. \nWater extract from different parts of \nB. napus \nduring water stress conditions under \nall plant development stages demonstrated variability in their effect on germination \nand growth of weed species between the water stress levels and within the same \nplant development stage. Furthermore, glucosinolates concentrations and \nIII \nmyrosinase activity in \nB. napus \ntissues \nwere \nsignificantly different between different \nplant parts \nduring the water stress conditions and under different plant development \nstages. This project has revealed that using water extracts from \nB \n. napus \nmay play \nan important role in \nweed species inhibition.