Volatile byproducts of carotenoid degradation as biomarkers of maize infestation by the maize weevil (Sitophilus zeamais) (Motsch.)

Authors: Broadhead, Geoffrey; LIU, HUI - Oak Ridge Institute For Science And Education (ORISE); SUMRALL, GRETCHEN - Oak Ridge Institute For Science And Education (ORISE); Block, Anna; Hunter Iii, Charles; Beck, John

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/13/2024
Publication Date: 12/21/2024
Citation: Broadhead, G.T., Liu, H., Sumrall, G.L., Block, A.K., Hunter Iii, C.T., Beck, J.J. 2025. Volatile byproducts of carotenoid degradation as biomarkers of maize infestation by the maize weevil (Sitophilus zeamais) (Motsch.). Journal of Agricultural and Food Chemistry. 73, 1835-1843. https://doi.org/10.1021/acs.jafc.4c09665.
DOI: https://doi.org/10.1021/acs.jafc.4c09665

Interpretive Summary: Corn is one of the most significant cereal crops and accounts for the vast majority of cereal consumption worldwide. In addition to its role as a cash crop and dietary staple, corn is a major source of raw materials in industry and post-harvest storage of this commodity is a significant component of national food security programs, international trade, and global agriculture economics. Insect infestation of corn during storage can result in significant losses to corn yield. The maize weevil is a major insect pest to stored corn and incurs serious damage. ARS scientists in Gainesville, FL compared odors of infested and non-infested corn to identify two specific odors that indicated maize weevil infestation in stored corn The odors that indicated infestation were also correlated with damage due to eggs laid by the maize weevils. Using this knowledge, points of commerce or corn storage facilities can use detection methods to locate and remove maize weevil-infested corn; thus, increasing the quality and marketability of the corn.

Technical Abstract: Maize, alongside wheat and rice, is one of the three most significant cereal crops accounting for the vast majority of cereal consumption worldwide. In addition to its role as a cash crop and dietary staple, maize is a major source of raw materials in industry and post-harvest storage of this commodity is a significant component of national food security programs, international trade, and global agriculture economics. Post-harvest insect infestation during storage can result in significant losses. The insect pest, maize weevil (Sitophilus zeamais), has been identified as a major obstacle in global maize production. Using gas chromatography and multivariate discriminant analyses we identified two volatile apocarotenoids indicative of maize weevil infestation in stored maize. Emission of these biomarker compounds responded rapidly to maize weevil infestation and showed a significant correlation with oviposition damage to the stored kernels. While the specific mechanism of volatile production remains elusive, the pattern of elevated biomarker emission after weevil exposure was consistent across each of the seven maize lines examined.