Location: Southern Insect Management Research
Title: Effects of soybean planting date on yield loss from defoliationAuthor
THRASH, BENJAMIN - UNIVERSITY OF ARKANSAS | |
CATCHOT, ANGUS - MISSISSIPPI STATE UNIVERSITY | |
GORE, JEFF - MISSISSIPPI STATE UNIVERSITY | |
COOK, DONALD - MISSISSIPPI STATE UNIVERSITY | |
MUSSER, FRED - MISSISSIPPI STATE UNIVERSITY | |
IRBY, TRENTON - MISSISSIPPI STATE UNIVERSITY | |
KRUTZ, JASON - MISSISSIPPI STATE UNIVERSITY | |
LORENZ, GUS III - UNIVERSITY OF ARKANSAS |
Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/9/2020 Publication Date: 1/18/2021 Citation: Thrash, B.C., Catchot, A.L., Gore, J., Cook, D.R., Musser, F.R., Irby, T., Krutz, J., Lorenz, G.M. 2021. Effects of soybean planting date on yield loss from defoliation. Journal of Economic Entomology. 114(2):993-997. https://doi.org/10.1093/jee/toaa280. DOI: https://doi.org/10.1093/jee/toaa280 Interpretive Summary: Historically, the recommended planting dates for soybean in the Mid-South region of the United States began in May and continued into June, with the dominant cultivars being maturity groups V, VI, and VII. Currently, no information exists regarding the effects of planting date on soybean yield loss from early season defoliation. In 2015 and 2016, to evaluate the effects of planting date on yield loss from defoliation,soybean were planted in field plots 2 weeks apart from early April to mid-June, for a total of six planting dates. Each planting date included a nondefoliated control and a 100% defoliation treatment where leaves were manually excised before bloom when plants had four fully developed trifoliate leaf nodes. Mean yield loss from defoliation varied across planting dates, with mid-April plantings having the least amount yield reduction, 573 kg/ha, and early-June plantings having the greatest yield reduction, 904 kg/ha. Percent yield reduction from defoliation increased as planting was delayed, suggesting that defoliation thresholds might need adjustment based on planting date and yield potential. However, more research is needed at lower levels of defoliation to accurately delineate such thresholds. Technical Abstract: Soybean, Glycine max (L.) Merr., is planted during 3.5–4 mo across the Mid-South United States. Currently, no information exists regarding the effects of planting date on soybean yield loss from early season defoliation. In 2015 and 2016, to evaluate the effects of planting date on yield loss from defoliation, soybean were planted in field plots 2 wk apart from early April to mid-June, for a total of six planting dates. Each planting date included a nondefoliated control and a 100% defoliation treatment where leaves were manually excised at the V4 growth stage. Mean yield loss from defoliation varied across planting dates, with mid-April plantings having the least amount yield reduction, 573 kg/ha, and early-June plantings having the greatest yield reduction, 904 kg/ha. Percent yield reduction from defoliation increased as planting was delayed, suggesting that defoliation thresholds might need adjustment based on planting date and yield potential. However, more research is needed at lower levels of defoliation to accurately delineate such thresholds. |