Allelopathic Effects of Rye (Secale cereal L.) on Corn (Zea maize L.) and Some of it's Important Weeds

There are several methods for weed management which one of them is using allelopathic crops. The present study was conducted to investigate the allelopathic effects of rye on seed germination and also seedling growth of sweet corn and some of it’s important weeds including redroot pigweed, lambsquarters, johnsongrass and wild prosomillet in laboratory and greenhouse, based on randomized complete block design (RCBD) with 4 replications. In the laboratory conditions, the effects of different concentrations of the water extract of rye aboveground parts (0, 2.5, 3.75 and 5.0 gr.100 ml-1 water) and in the greenhouse conditions the effects of aboveground parts biomass (0, 4, 8, 16 and 32 gr of rye biomass per 1 kg soil) on germination and seedling growth indices of sweet corn and it’s major weeds were investigated. Rye aqueous extracts showed a negative effect on germination and seedling growth parameters of them. So that, in laboratory conditions, the seed germination of wild proso, lambsquarters, johnsongrass and redroot pigweed were reduced 84.7, 75, 53.3, and 31 %, respectively in the highest concentration of rye extract compare of control. In contrast, there was not a considerable impact on corresponding indices of sweet corn. Seedling emergence of lambsquarters, johnsongrass, redroot pigweed, and wild proso were reduced 79.8, 75, 72.8, and 68.3 % in 32 gr of rye biomass per 1 kg soil, respectively (in greenhouse conditions). Emergence rate of these weeds was reduced by rye biomass. Lambsquarters and redroot pigweed dry weight and length of root and shoot were reduced significantly by all levels of rye biomass. Finally rye residues have an enormous potential to suppress weed species with no harmful influence on sweet corn.