Effect Of Seed Mass And Emergence Delay On Soybean Yield And Quality

Soybean (Glycine max L. Merr.) growers are continuously looking at integrating low cost management strategies to increase soybean seed yield. Although the influence of the size of the seed (seed mass) on soybean seed yield and quality has been examined in the past, variable results coupled with modern genetics and agronomic practices (e.g., treated seed and decreased seeding rates) as well as increased seed cost have growers and crop consultants revisiting this question. Therefore the objective of this study was to evaluate the effect of planted seed mass on days to emergence and their interaction on soybean seed yield, seed protein and oil content, and harvested seed mass using modern soybean genetics. Field trials were established at four locations across Wisconsin and Iowa in 2008 and 2009 for a total of eight environments. During the 2 yr of the experiment, there was no evidence that seed mass had an effect on soybean seed yield and quality characteristics. However, the seed mass by days to emergence interaction was significant for both soybean seed yield and quality. As seed mass increased and emergence delayed, the maximum observed yield loss reached 6.9 kg ha(-1), the maximum oil increase reached 4 g kg(-1), and maximum protein yield decrease reached 2.4 kg ha(-1). Biologically these effects were considered of low practical importance. According to the results of this study, seed mass should not be a driving factor for farmers or consultants when selecting a soybean cultivar for maximum seed yield.