Changes in seed quality during seed development and maturation in four cultivars sesame (Sesamum indicum L.)

In order to achieve high quality seeds, producers must be able to estimate the accurate harvest maturity time seeds. The objective of this study was to investigate changes in seed quality during seed development and maturation in the two cultivars native of the Sari and Gorgan and two cultivars modified of the Darab14 and Yellowhite. A field experiment was conducted in during 2009 at Gorgan University of Agricultural Sciences and Natural Resources,Gorgan,Iran. The results indicated that physiological maturity (maximum dry weight of seed) achieved at about 68 (889), 70 (957), 77 (1036) and 75 (1012) days after flowering (growth degree days) for Yellowhite, Darab14, Gorgan and Sari cultivars, respectively. At this date, the seed moisture content was 29, 40, 27 and 16% (wet basis), respectively. Maximum seed quality occurred at 2 and 24 days later for cv. Darab14 and Yellowhite, and 10 and 6 days earlier for cv. Sari and Gorgan, when compared to physiological maturity of seeds. The results indicated that there was significant difference as aspect the time to achieve to maximum seed quality and physiological maturity in sesame. Generally, for to achieve high quality seeds in sesame, must was done harvest at 900-1000 degree-days after flowering. At the date, the moisture content of seeds were between 25-35% (wet basis) and color lower and middle capsules were change from green to brown or yellow (depending on cultivar). Hence, color identification of the capsules can be used as an additional indicator for sesame harvest.