Luteolin Effects on Mortality, Development and Population Parameters of Frankliniella occidentalis (Pergande)

Luteolin, as one of the flavonoids, has demonstrated repellent and toxic effects on various insect pests; however, its influence on thrips development and fecundity remains poorly understood. In this study, we investigated the toxicity of luteolin on the survival of a worldwide insect pest, the western flower thrips (WFT) (Frankliniella occidentalis Pergande), its effects on WFT feeding and oviposition preferences, and its sublethal impacts on development and fecundity. Results showed that both adult and nymphal WFT mortality rates increased with luteolin concentration. In choice assays, luteolin exhibited repellent effects on nymphal feeding and adult oviposition. At a sublethal concentration of 0.1 mg/mL, luteolin significantly shortened the adult lifespan, and reduced fecundity, intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R₀), suppressing WFT population growth. This study demonstrates that luteolin has the potential to be developed as a botanical pesticide for thrips management, combining with toxic and reproduction-inhibiting activities.