Effect of Eliminating of Irrigation at Different Growth Stages on Seed Yield and Some Agronomic Traits of Two Sesame Genotypes

This study was carried out as factorial arrangement in randomized complete block design with three replications in two years (2006 and 2007) in Jiroft and Kahnouj Agricultural Research Center, Jiroft, Iran. The first factor was eliminating of irrigation at different growth stages at five levels: 1- eliminating irrigation from 4-6 leaf stage to prior to flowering, 2- eliminating irrigation from 4-6 leaf stage to full flowering, 3- eliminating irrigation from flowering to the end of the growing season, 4- eliminating irrigation from 4-6 leaf stage to prior to flowering and from flowering until the end of the growing season, 5- Full irrigation based on 100 mm evaporation from class A pan (control), and the second factor was sesame genotypes, local Jiroft variety and JL-13 line. Branch plant-1, capsule plant-1, seed capsule-1, 1000 seed weight, seed oil content, plant height, biological yield, seed yield and harvest index were measured. Results showed that eliminating of irrigation at different growth stages significantly affected seed yield, capsule plant-1 and seed capsule-1, 1000 grain weight, branch plant-1, plant height, biological yield and harvest index. Eliminating of irrigation at different growth stages significantly reduced grain yield, yield components, branch plant-1, plant height, biological yield and harvest index. The least reduction rate in seed yield, yield components, lateral branches, plant height, biological yield and harvest index was recorded in eliminating of irrigation from 4-6 leaf stage to prior to flowering, and it had the highest seed yield following the control. Eliminating of irrigation from 4-6 leaf stage to prior to flowering and from flowering to the end of growing season had a considerable impact on seed yield and yield components and had the lowest seed yield. JL-13 line produced higher seed yield under stress and non-stress conditions.