Seed yield and some yield components of sesame as affected by irrigation interval and different levels of N fertilization and superabsorbent
In order to study the effect of different irrigation, N and superabsorbent levels on yield and yield components of sesame, a field experiment was conducted in Khosf Region, Birjand, Iran in 2009 as a split-split plot design based on a randomized complete block design. The treatments included irrigation interval at three levels of six, 12 and 18 days as main plot, N fertilization level at three levels of 0, 100 and 200 kg.ha-1 as sub-plot and superabsorbent level at two levels of 0 and 200 kg.ha-1 as sub-sub-plot. Results of analysis of variance showed that irrigation interval and N fertilization levels significantly affected seed yield, single-plant biomass yield, straw yield, seed yield per capsule and seed yield per plant, but their effect on seed harvest index was not significant. Means comparison revealed that as irrigation interval was increased from six to 18 days, seed yield, single-plant biomass yield, straw yield, seed yield per capsule and seed yield per plant were significantly decreased by 44.5, 54.2, 44.31, 35 and 54.4%, respectively. Also, the increase in N fertilization level from 0 to 200 kg.ha-1 decreased them by 25.6, 16.7, 16.2, 18.8 and 28.8%, respectively. In total, according to the results, six days irrigation interval fertilized with 200 kg N.ha-1 is recommended for the cultivation of sesame in Birjand, Iran.
Key words: Sesame, irrigation, nitrogen, superabsorbent, seed yield.