Sublethal effects of flonicamid on the population growth of the grain aphid <i>Rhopalosiphum padi</i> (L.) (Hemiptera: Aphididae)

<i>Rhopalosiphum padi</i> is an important grain pest, causing severe losses during crop production. As a systemic insecticide, flonicamid can control piercing-sucking pests efficiently. In our study, the lethal effects of flonicamid on the biological traits of <i>R. padi</i> were investigated via a life table approach. Flonicamid is highly efficiently toxic to <i>R. padi</i>, with an LC₅₀ of 9.068 mg L^-1. The adult longevity and fecundity of the <i>R. padi</i> F₀ generation were markedly reduced under the LC₂₅ and LC₅₀ concentrations of flonicamid exposure. In addition, negative transgenerational effects on <i>R. padi</i> were observed under exposure to lethal concentrations of flonicamid, with noticeable decreases in the reproductive period, adult longevity, total longevity, and total fecundity of the F₁ generation under the LC₂₅ concentration of flonicamid. Furthermore, the third nymph stage (N3), preadult stage, duration of the adult pre-reproductive period, duration of the total pre-reproductive period, reproductive period, adult longevity, total longevity, and total fecundity of the F₁ generation were significantly lower under treatment with the LC₅₀ concentration of flonicamid. The life table parameters were subsequently analysed, revealing that the intrinsic rate of increase (<i>r_m</i>) and the net reproductive rate (<i>R</i>₀) were significantly lower but that the finite rate of increase (<i>λ</i>) and the mean generation time (<i>T</i>) were not significantly different under the LC₂₅ and LC₅₀ concentrations of flonicamid. These data are beneficial for grain aphid control and are critical for exploring the role of flonicamid in the integrated management of this key pest.