Effect of weeds Interference on Yield and Yield Components of Common Bean (Phaseolus vulgaris)

In order to determine the effect of weeds on yield and yield components of common bean (Phaseolus vulgaris L.)، this research was carried out as split plot in randomized complete block، with four replications، in Khomein Bean Research Station during 1999 and 2000. There were two plots including naturally contaminated with weeds، and complete weed control. There were also eight subplots containing the following ban cultivars/lines: Dehghan، Daneshkadeh، Naz، Goli، Talash، Mahali Khomein، Sadri and Coc16 bean. Mean comparisons of traits showed that presence of weeds caused loss of 45% in yield، 39% in number of seeds for plant، 5. 1% number of seeds per pod، 36% number of pods in studied cultivars/lines. Goli and Talash with the highest ability of weed competition were superior among studied cultivars. The coefficients of correlation indicated negative and significant correlation of weed dry weight with yield.