Inheritance of polygenic but stable pyriproxyfen resistance in a bio-control agent Chrysoperla carnea (Neuroptera: Chrysopidae): cross-resistance and realized heritability.

Abstract

Chrysoperla carnea (Neuroptera: Chrysopidae) is a voracious predator frequently used in biological control programs to suppress pest populations of economic importance. However, it performs its duty in a challenging environment where various stress factors such as non-target effects of insecticides limit expected outcomes. A study providing details of genetics, cross-resistance, realized heritability, and stability of insect growth regulators (IGRs) resistance such as pyriproxyfen in this bio-control agent is essential. Selection with pyriproxyfen, an IGR, resulted in 3092.10-fold and 39.60-fold resistance when judged against Susceptible and Field Pop, respectively. Very low cross-resistance to buprofezin while no cross-resistance to acetamiprid and spinosad was observed. Incompletely dominant, autosomal and polygenic resistance was also associated with high realized heritability (h2 = 0.35). Furthermore, resistance to pyriproxyfen was stable in this bio-control agent. These findings make Chrysoperla carnea an ideal fit in integrated pest management (IPM) programs where biological control approaches are employed in combination with IGRs sprays to control various insect pests especially Whitefly, Bemisia tabaci. Releasing pyriproxyfen-resistant Chrysoperla carnea in a multi-sprayed cropping environment would help to keep pest population below economic threshold level. It would also minimize risk of insecticide resistance development in pests surviving even after several insecticide applications. © 2020 Society of Chemical Industry.