بررسي اثرات آللوپاتيك عصاره آبي بقاياي سه رقم كلزا در غلظت هاي مختلف بر جوانه زني و رشد دانه رست برخي علف هاي هرز

Allelopathic Effects of Three Cultivars of Rapeseed (Brassica nap us L.) Aqueous Extracts at Different Concentrations on Germination and Seedling Growth of Some Weeds

Allelopathy is an interference mechanism in which living or dead plants release allelochemicals exerting an effect (mostly negative) on the associated plants, and this might be a chance to reduce the use of herbicides and could be an additional tool to control herbicide-resistant weeds. The species of Brassica tissue such as rapeseed could be attributed to their ability to release toxic substances in the environment and to create an unfavorable environment for weed germination and establishment .The objective of this study was to select suitable cultivars of rapeseed with high allelochemical and use of them in weed management. Accordingly, an experiment was carried out to assess allelopathic potential of cultivars of rapeseed vegetative parts on some common weeds in Kermanshah region (wild barley, wild oat, tumbleweed amaranth and curly dock) in randomized completely block design. The factors consisted of cultivars (opera, talaieh and okapy) of rapeseed and concentration (100%, 50% and control).Measured traits were germination percentage, inhibitory percentage, speed of germination, rootlet length and hypocotyl length. The bioassay experiments showed that by increasing the aqueous extract concentrations of rapeseedʹs cultivars, the germination rate and seedling crops of weed were decreased (P < 0.001). Especially the residual extract of rapeseed had most effect on germination and seedling growth of tumbleweed amaranth. In particular, opera extracts caused greater inhibitory percentage on weeds than talaieh and okapy.