Evaluation of Tolerance of Chickpea Genotypes to Weed Competition

To determine chickpea genotypes competition ability against weeds, 49 chickpea genotypes were evaluated under weeds-free and weedy conditions using 7 × 7 simple lattice design with two replications in 2006 in Kheirabad Agricultural Research Station of Zanjan, Iran. Each plot was equally divided into two sub-plots in which the first sub-plot was weed-free and the second was left with weeds to grow naturally. Results of correlation between seed yield and its components with weeds density (in two growth stages) and dry weight (in one grown stage) showed that weeds density in early days of plant growing had the highest reduction of seed yield. Factor and correlation analyses and biplot method of grain yield in both conditions showed that MP, GMP, STI indices were more suitable for identification of genotypes with higher yield stability. Cluster analysis based on tolerance indices and yield under weeds-free and weedy conditions grouped chickpea genotypes in four clusters and genotypes of higher tolerance were located in the first and second clusters. The more sensitive genotypes with the largest margin were located in the fourth cluster.