Pesticide-induced planthopper population resurgence in rice cropping systems

Authors: WU, JIN-CAI - Yangzhou University; GE, LIN-QUAN - Yangzhou University; LIU, FANG - Yangzhou University; SONG, QISHENG - University Of Missouri; Stanley, David

Submitted to: Annual Review of Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/30/2019
Publication Date: 10/14/2019
Citation: Wu, J., Ge, L., Liu, F., Song, Q., Stanley, D.W. 2019. Pesticide-induced planthopper population resurgence in rice cropping systems. Annual Review of Entomology. 65:409-429. https://doi.org/10.1146/annurev-ento-011019-025215.
DOI: https://doi.org/10.1146/annurev-ento-011019-025215

Interpretive Summary: Planthopper population resurgence refers to rapid development of extraordinarily large pest populations that lead to very serious crop and economic losses. Planthoppers are very small insects with high reproductive capacity. They destroy cereal crops, such as rice, wheat and corn in two ways. One, they exert tremendous feeding damage by sucking up plant juices and, two, they transmit viruses that cause destructive plant diseases. We discuss the fundamental causes of population resurgence, specifically the applications of agricultural chemicals that kill and/or disable beneficial arthropods. Beneficial arthropods provide valuable biological control services in cropping systems as natural enemies, predators and parasites, of planthoppers. In the absence of these beneficial insects, pest planthopper populations grow unchecked. Some agricultural chemicals also lead to completely unforeseen consequences, that is, the increased reproductive potentials through their impact on cellular events that lead to an overall increase in egg production. Planthopper population resurgence, then, results from loss of biological control services and increased reproduction. In this paper, we provide leadership necessary to improve current planthopper management practices and suggest research necessary to understand and mitigate planthopper population resurgence.

Technical Abstract: Planthoppers are serious rice pests in Asia. Their population resurgence was first reported in the early 1960’s, caused mainly by insecticides that indiscriminately killed beneficial arthropods and target pests. The subsequent resurgence involved two mechanisms, the loss of beneficial insects and insecticide-enhanced planthopper reproduction. Here, we identify two forms of resurgence, acute and chronic. Acute resurgence is caused by traditional insecticides with rapid resurgence in the F1 generation. Chronic resurgence follows application of modern pesticides, including fungicides and herbicides, with low natural enemy toxicity coupled with stimulated planthopper reproduction. This chemical-driven syndrome of changes leads to later resurgence in the F2 or later generations. Chronic resurgence poses new threats to global rice production. Here, we review findings on the physiological and molecular mechanisms of chronic planthopper resurgence and suggest research directions that may help manage these new threats.