Allopathic effects of Chenopodium album, Amaranthus retrofelexus and Cinodon dactylon on germination and growth of rapeseed

This research was conducted to evaluate the allelopathic effects of root and shoot extracts of three abundant weeds of rapeseed fields in Iran including: Chenopodium album, Amaranthus retrofelexus and Cinodon dactylon on germination and growth stages of rapeseed. Experimental design was factorial based on completely randomized design (CRD) at three replicates. Treatments were control and shoot and root extracts of the mentioned weeds. Results revealed that studied weeds disturbed rapeseed germination and growth by producing allelopathic substances.Weed extracts influenced seedling length, seedling dry weight, germination percentage and germination duration. C. album shoot extract and root extract of C. dactylon inhibited rapeseed germination at all. In laboratory tests, extracts of other parts of the weeds inhibited seedling dry weight and length up to 4.6% and 98.8%, respectively. In greenhouse experiments, weed extracts affected root and shoot dry weight, leaf area, and biomass of rapeseed, significantly. They also decreased rapeseed root length at least 5.8% and it’s biomass up to 8.87%.