The Effect of Weeding Time on Yield and Yield Components of Sesame (sesamum indicum L.)

In order to evaluate the weeding time on yield and yield components of sesame, an experiment carried out in a split plot complete randomized blocks design with three replications in the Faculty of Agriculture, Ferdowsi University of Mashhad, in 2009. Treatments included sesame varieties (Kalat genotype and Oltan cultivar) as main plot, and weeding from the emergence up to 20, 30, 40, 55 and 70 days after emergence and weeding afterwards the 20, 30, 40, 55 and 70 days after emergence alongside the no weeding in whole growing season and also weeding in whole growing season as allocated as sub plots. The results showed that with increasing interfering period at the beginning or at the end of growing season , yield and yield components of sesame were decreased significantly (p≤ 0.01). Therefore, grain yield increased in the longer periods of weeding. The number of capsules per plant was the most important yield component that had high correlation (r = 0.70**) with the yield. Interference of weeds up to 30 and 40 days after emergence reduced yield in Kalat and Oltan respectively, though interference after that period reduced the yield of both genotypes