Monday, November 5, 2007 - 11:30 AM
69-8
Planting Date Impact on Soybean Yield, Seed Quality and Grain Composition.
Andrew Robinson1, Shawn Conley2, and Jeffrey Volenec1. (1) Purdue University-Agronomy Dept., Purdue University, 915 W State St., West Lafayette, IN 47907, (2) 915 West State St, Purdue University-Agronomy Dept., Purdue University, Department of Agronomy, West Lafayette, IN 47907-2054
With a major shift in soybean [Glycine max (L.) Merrill] planting date, little research has been published on the performance of soybean planted in March, April, or early May in the Upper Midwest. Our objective was to evaluate the impact of planting date and maturity group on grain yield and seed oil and protein composition. Our hypothesis was that early planting increases yield as well as total oil. Three cultivars differing in maturity group (2.6, 3.2, and 3.7) and six planting dates (planted in approximately two week intervals starting the last week in March) were seeded at West Lafayette , Indiana in 2006 and 2007. The experimental design was a randomized complete block split-plot design with main plots as planting date and maturity groups as sub-plots. Soybean was planted with a no-till drill in 38-cm rows at 370,000 plants ha-1. Results from year one indicated that planting in March, April, and early May increased yield as well as seed oil concentration. Increased grain yield in the first four planting dates was attributed to more nodes, pods, and seeds per plant when compared to plants seeded at the last two planting dates. Our results indicated a broad planting date window from which soybean grain yield and oil can be maximized.