Overview of risk factors and strategies for management of insect-derived ear injury and Aflatoxin accumulation for Maize grown in subtropical

Authors: PRUTER, LUKE - Texas Agrilife; BREWER, MICHAEL - Texas Agrilife; Weaver, Mark

Submitted to: Journal of Integrated Pest Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/17/2020
Publication Date: 6/12/2020
Citation: Pruter, L.S., Brewer, M.J., Weaver, M.A. 2020. Overview of risk factors and strategies for management of insect-derived ear injury and Aflatoxin accumulation for Maize grown in subtropical. Journal of Integrated Pest Management. 11:1-8. https://doi.org/10.1093/jipm/pmaa005.
DOI: https://doi.org/10.1093/jipm/pmaa005

Interpretive Summary: Aflatoxin contamination of corn is often associated with insect feeding damage. The frequency and level of contamination results from interactions between the host plant, the pathogen, the insects and numerous environmental factors, including temperature, drought stress and management practices. This manuscript describes those interactions and how multiple practices can be combined and implemented to promote yield and minimize aflatoxin contamination of corn.

Technical Abstract: Pest and disease risk factors causing maize yield and kernel quality issues in subtropical areas of North America (between 35°N and 23.5°N latitude) are reviewed: preharvest Aspergillus flavus (Link) (Deuteromycetes: Moniliales) infection and propagation in maize ears and ear injury principally caused by Helicoverpa zea (Boddie) and Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). Risk is affected by potentially interacting factors of maize genetics, ear feeding with insects, fungal inoculum and growth, and weather (rainfall, temperature, and humidity).This review gives special attention to integration of the most efficient pest and disease management strategy combinations and the potential interaction of insect ear feeding and A. flavus occurrence. Management strategies reviewed include maximizing partial genetic resistance to A. flavus and selection of appropriate hybrids for the area, biological control of A. flavus using non-aflatoxigenic strains, avoiding pests and diseases using cultural practices like early planting, and reducing H. zea and S. frugiperda ear injury using Bt transgenes. Understanding the combined influences and identifying combined management approaches may lead to reduced aflatoxin risk and maintaining yield. This review focuses on subtropical areas of North America because the amount of maize produced in warm environments within or similar to subtropical maize production areas is likely to increase due to projected increases in demand for maize and predicted increases in temperature may increase pest and disease risk.