Yield and yield Components of Soybean Cultivars as Affected by Planting Date

In order to investigate the effect of planting date on yield and yield components of four soybean cultivars, an experiment was conducted based on split plot in randomized complete block design with four replications in Agricultural Research Station in Ilam province, Iran in 2011-2012 growing season. Factors of experiment consisted of four planting dates (20 June, 30 June, 1 May , 10 May) and cultivars were consisted of four soybean cultivars (M7, M9, L17 and Williams. Result of this experiment showed that the effect of planting data and cultivars on yield and component was significantly effect. Planting date on plant height, seed weight, seed yield, and biological yield had a significant effect, so that the maximum plant height, seed weight, seed yield, biological yield was on 10 May. Cultivars effect was significant for all studied traits. Williams cultivar due to the number of pods per plant, seed weight, seed yield, biological yield was higher than other varieties. Interaction effect between planting date and cultivars on seed yield, 100-seed weight and plant height was significant. The highest seed yield (3107 kg.ha-1) was gained on 10 May with Williams varieties. In general, the results of this study indicated that planting date of 10 July and Williams cultivar were suitable for soybean planting in the Ilam region.