Submitted to: HortScience
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/6/2008
Publication Date: 9/20/2008
Citation: Williams, M.M. II. 2008. Sweet Corn Growth and Yield Responses to Planting Dates of the North Central United States. HortScience. 43(6):1775-1779. Interpretive Summary: Manipulating how the environment affects the crop has been a successful approach to improving crop production. Crop planting dates, which range across three months in north central U.S. sweet corn production, influence the type and severity of stresses the crop must endure. Unfortunately, little is known about the response of sweet corn to planting dates. In field research, we found that sweet corn responded consistently to changing environmental conditions brought about by the long planting season from mid-April to early-July. Crop development was more rapid as planting was delayed from mid-April to early-July. As the season progressed, sweet corn also grew taller yet with fewer, slower-emerging leaves. Leaf biomass was unaffected by planting date. Yield consistently decreased in the early-July planting date; however, not all hybrids tolerate stresses the same and further research is needed. This work demonstrated that the crop canopy undergoes distinct changes as planting date is delayed, and crop management may benefit from exploiting this information.
Technical Abstract: Sweet corn is planted over a three-month period in the north central U.S. in order to extend availability for fresh market and processing; however, the extent to which development and growth of sweet corn changes during this period is unreported. Field experiments were conducted in 2006 and 2007 to determine the effect of five planting dates, ranging from mid-April to early-July, on sweet corn establishment, growth, and yield components. Day length at the time of silking was within 12 minutes for each planting between the two years and decreased from 15.1 hours in the mid-April planting to 13.7 hours in the early-July planting. Development took 13 to 25 fewer days from emergence to silking for the hybrid ‘BC0805’, an 82-day augmented sugar enhancer endosperm type, as planting was delayed from mid-April to early-July. Maximum height generally increased through planting dates, with as much as 23% taller plants in early-July versus mid-April planted sweet corn. While leaf mass was unaffected by planting date, maximum leaf number and rate of leaf appearance steadily decreased with later planting dates. Lower reproductive and total biomass at silking, as well as marketable ear yield components, were lowest in the early-July planting date and were associated with presence of maize dwarf mosaic virus in leaf samples. In response to environmental conditions, the crop canopy undergoes distinct morphological changes as planting is delayed, and those changes may have implications for crop production.