Investigation of seed size effect on pod formation and yield in three soybean cultivars

In order to study the effect of seed size and cultivar on pod formation and yield, a factorial experiment was performed as a Randomized Complete Block Design (RCBD) with three cultivars (williams, Sahar and Katol) and three seed size (small, medium and large) in 2011 The results of analysis of variance showed that there were significant difference between cultivars for pod setting and yield at 1%probability level. Mean comparison between cultivars indicted that highest pod setting was observed in Sahar with 64 pods and lowest in Katol with 36 pods. Based on the observation, it seems that unfertile pods in the latter one is the indicator of its susceptibility compared to other cultivars resulting in decreased number of fertile pods. Mean yield comparison revealed that he highest yield (2984 kg/ha) was produced by Williams while lowest yield (2246kg/ha) belonged to Katol.The analysis of variance of the dates indicated that there was significant difference between seed sizes (Small, Medium and Large)at 1% probability level for pod fertility and yield. Mean comparison between seed size for pod setting indicated that large-and small sized seeds produced the highest (57) and lowest (43) number of pods, respectively. The mean comparison of yield under the influence of various sizes of seeds revealed that the highest yield (3192 kg/ha) was produced in sowing large seeds whereas the lowest yield (1981 kg/ha) was obtained with small seed size. Based on the results, seed size was effective in pod setting and producing suitable yield, and as a consequence it was effective for soybean seed increase.
een 1000-SW and seed filling rate, explaining 67 and 74% of the variation for Hyola401 and RGS003, respectively. The strong relationships of SW with temperature, PTQ and CGR during SFP, and the duration and rate of SFP over different environmental conditions, SDs and cultivars, showed these variables to be generally applicable in SW determination.