Pesticide-Induced Planthopper Population Resurgence in Rice Cropping Systems

Abstract

Planthoppers are serious rice pests in Asia. Their population resurgence was first reported in the early 1960s, 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. In this review, 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. The chemical-driven syndrome of changes leads to later resurgence in the F2 or later generations. Chronic resurgence poses new threats to global rice production. We review findings on the physiological and molecular mechanisms of chronic planthopper resurgence and suggest research directions that may help manage these new threats.

Triazophos‐induced vertical transmission of rice stripe virus is associated with host vitellogenin in the small brown planthopper Laodelphax striatellus

“…In BPH, triazophos also could increase the contents of fat body protein and ovarian protein . In addition, exposure to triazophos increased the titers of circulating juvenile hormone, the contents of unfractionated lipids and soluble sugar that supported reproduction of planthoppers . Thus, triazophos was generally considered to be a classic resurgence‐inducing insecticide …”

“…21,22,24,25,30 In addition, exposure to triazophos increased the titers of circulating juvenile hormone, the contents of unfractionated lipids and soluble sugar that supported reproduction of planthoppers. 19 Thus, triazophos was generally considered to be a classic resurgence-inducing insecticide. 25,27 Considering the important role of Vg in transovarial transmission of RSV, 35 we injected dsVg to further investigate the role of Vg.…”

“…18 Previous studies showed that sublethal doses of triazophos could stimulate reproduction in planthoppers. 19,20 Triazophos treatment significantly increased the protein contents of ovary and fat body, 21,22 circulating juvenile hormone titers, 23 the amounts of unfractionated lipids 19 and soluble sugar contents in the females of brown planthopper (BPH). 24,25 These metabolites provide the energy that induces BPH reproduction and resurgence.…”

“…Insecticides degrade via photolysis and hydrolysis in the field, thereby insect pests prolonged exposure to different sublethal concentrations of insecticides . Previous studies showed that sublethal doses of triazophos could stimulate reproduction in planthoppers . Triazophos treatment significantly increased the protein contents of ovary and fat body, circulating juvenile hormone titers, the amounts of unfractionated lipids and soluble sugar contents in the females of brown planthopper (BPH) .…”

Functional Analysis of Nuclear Factor Y in the Wing-Dimorphic Brown Planthopper, Nilaparvata lugens (Hemiptera: Delphacidae)

“…Wing dimorph and high fecundity are the two most important biological features contributing to the ecological success of the BPH ( Zhang et al, 2019 ). Recently, facilitated by the development of genetic tools ( Xu et al, 2013 ; Xue et al, 2018 ) and genomic information ( Xue et al, 2014 ), the molecular basis underlying wing dimorphism ( Xu et al, 2015 ) and population resurgence ( Wu et al, 2020 ) are emerging, which offers a basis for the design of new control agents to combat BPH infestation.…”