Investigation of Red Bean Varieties Tolerance in Various Densities to Weed Competition

To evaluate the competitive ability of red bean cultivars with weeds in different planting patterns, this research was conducted in Agriculture and Natural Resources Research Center of Zanjan. It was performed as a Split Factorial based on Completely Randomized Block Design in three replicates for two years. Main plot included two levels with and without presence of weeds. Subplots included red bean cultivars (Sayyad, Derakhshan and local cultivar of Zanjan), Planting row distance (20 and 30 cm) and plant densities (20, 30, 40 and 50 plants per square meter). To measure the competitive ability of genotypes, different tolerant of non-parametric indices were used. Based on the results effects the main factors were significant at 1% probability level for all traits, except 100 grain weight and plant height. Cultivar effects on biomass yield and other recorded traits in the 50% flowering stage were significant at 5% and 1% probability levels respectively. Effect of planting density on biomass and number pods were significant (P>1% ) in the four-leaf and 50% flowering stages. The highest (7.8) and lowest(6.08) number of pods were obtained with 20 and 50 plant densities respectively. In this research, local cultivar showed the highest tolerance to weeds with 30 and 40 plants per m2. The cultivar also showed the same result when 40 plants per m2 and 20 row spacing were used.