D-limonene binds the target gene odorant-binding protein 3 to control Bemisia tabaci

Abstract

Bemisia tabaci (Gennadius) is an important global invasive pest, which damages plants by feeding on phloem sap and causes great losses to agricultural production. At present, the management of B. tabaci still relies on insecticides. Based on the emergence of the insecticide resistance and the pursuit of environmental friendliness, more green control methods have been generated. Insects rely on odorant-olfactory proteins to identify specific volatiles and locate hosts, and these volatiles can be exploited in agricultural pest control. This study evaluated the control efficacy of d-limonene, a common volatile in three avoidant plants. Our results showed that d-limonene had a repelling effect on B. tabaci, and the LC50 value of d-limonene was 81.623 ppm. Moreover, the LC50 of bifenthrin and flupyradifurone were reduced by 25.2% and 38.7% when mixed with d-limonene. The underlying molecular mechanism of d-limonene recognition by B. tabaci was investigated. Treating B. tabaci with dsBtabOBP3 increased the control effect of d-limonene, and the LC50 of d-limonene, mixture (L+B) and mixture (L+F) were decreased by 32.6%, 38.4% and 33.1%. These results indicated that specific volatiles could directly bind to target genes and therefore enhance the control effect of B. tabaci.