A comparison of the development time, survival, and fecundity of black pecan aphid feeding on foliage of four pecan cultivars.

Abstract

Development time, survival, and fecundity of the black pecan aphid (BPA), [Melanocallis caryaefoliae (Davis)] (Hemiptera: Aphididae), were assessed on four commercial pecan cultivars (Avalon, Desirable, Lakota, and Sumner) using a detached leaf method and using the age-stage, two-sex life table analysis. Results demonstrated a significant influence of pecan cultivars on the aphid's performance. BPA had a longer nymphal duration and reduced fecundity, which contributed to lower demographic parameters, including an intrinsic rate of increase (r = 0.31 d⁻¹), finite rate of increase (λ = 1.36 d⁻¹), and net reproductive rate (R0 = 50.91 nymphs/female) on Desirable cultivar, making it the least suitable cultivar among all. In contrast, the Lakota cultivar supported the highest demographic parameters (r = 0.36 d⁻¹, λ = 1.43 d⁻¹, and R0 = 95.80 nymphs/female) of BPA, indicating it as the most favorable host among the evaluated cultivars. However, there is no significant difference in preadult survival rate among the cultivars. The variability in aphid performance across the cultivars likely reflects differences in host plant resistance, highlighting the potential to integrate pest biology and demographic information into selecting resistant cultivars for effective BPA management in pecan crops.