Effect of Cultivar and Different Plant Density of Red Bean (Phaseolus vulgaris L.) on Population and Weed Growth

This study was carried out to investigate the competition of weeds with different cultivars and planting densities of red beans over two years. The experiment was completely randomized block with factorial arrangement and three replications per treatment. The treatments included beans cultivars (Sayyad, Derakhshan and Zanjan local seed lot), row spacing (20 and 30 cm)anddensities (20, 30, 40 and 50plants persquare meter). The number and the dry weight ofweedspecieswere determined at four-leafstage, 50% flowering and maturity. The resultsshowed thatweedspecies of bean were green foxteil(Setaria viridis),tumble weed(Amaranthus albus),lambsquarter(Chenopodium album),barnyardgrass(Echinochloa crus-galli)andredroot pigweed(Amaranthus retroflexys) within two years. Zanjan local seed lot with densities of 30 and 40 plants per square meter and row spacing of 30 cm and densities of 40 plants per square meter with 20 cm row spacing were the most tolerance to the presence of weeds along with higher yield.