Evaluation of drought tolerance in sesame (Sesamum indicum L.) genotypes at different growth stages

Drought is a wide spread problem، which is seriously influencing crop production، mostly in arid and semi-arid regions. This study was conducted in two separate experiments. In field experiment، main plots were the different levels of irrigation، and the sub-plots were eight different genotypes of sesame including (Gorgan، Shiraz، Markazi، Birjand، Arzoieh، Sirjan، Ardestan and Safiabad). Results showed that different irrigation treatments have significant effect on all of the studied traits، except for the number of capsule per plant. The highest (1. 15 ton/ha) and lowest (0. 24 ton/ha) values of seed yield were observed in Arzoieh and Gorgan، respectively. Drought tolerance was evaluated at the base of field capacity (FC) (100، 80 and 50 %) in greenhouse conditions. Different traits including leaf number، shootlet length، rootlet length، dry weight and wet weight of shootlets and rootlests were measured. The highest and lowest values of dry weight were observed in Arzoieh Arzoieh (0. 015 g) and Gorgan (0. 002 g) genotypes، respectively.