Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 21, 2008
Publication Date: February 1, 2009
Citation: Nagoshi, R.N. 2009. Can the amount of corn acreage predict fall armyworm infestation levels in nearby cotton? Journal of Economic Entomology. 102(1):210-218. Interpretive Summary: Fall armyworm, is an important agricultural pest of a number of crops in the western hemisphere, including corn and cotton. Scientists at the ARS Center for Medical, Agricultural and Veterinary Entomology in Gainesville Florida found correlations between the levels of corn acreage planted in southern states and the level of fall armyworm infestation in regional cotton acreage. The results demonstrate that it may be possible for the first time to predict the severity of infestation in cotton early in the growing season, potentially providing growers a period of several weeks to prepare.
Technical Abstract: Fall armyworm is a major pest of corn and a significant, but more sporadic, pest of cotton in the western hemisphere. Previous studies showed that the cotton infestations primarily involve a fall armyworm subpopulation known as the “corn-strain” for which corn is the preferred host plant. It was suggested that the fall armyworm infesting cotton originated in corn and spread into secondary hosts as their numbers increased. Consistent with this proposal was the finding that high positive correlations exist between corn acreage and fall armyworm infestation levels in cotton, and that these occurred between areas that are either geographically close or along plausible migration pathways. Formulae were derived from scatter plot and linear regression analysis that can predict infestation levels in cotton based on corn acreage, provided that the correlations exhibited in the most recent 10 years (1997-2006) are still relevant. The implications of these studies for describing and predicting fall armyworm population movements are discussed.