Biology and Demographic Parameters of Aonidiella aurantii (Hemiptera: Diaspididae) on Different Citrus Rootstocks

Abstract

The California red scale, Aonidiella aurantii (Hemiptera: Diaspididae), is a destructive pest of citrus worldwide, causing severe yield and quality losses by feeding on plant sap and weakening tree vigor. The present study evaluates the biology and demographic parameters of A. aurantii on different citrus rootstocks under controlled laboratory conditions to understand host-mediated effects on pest performance. Developmental duration, survival rate, fecundity, and adult longevity were recorded across successive life stages on selected rootstocks. Results revealed significant variation in biological performance depending on the rootstock, indicating strong host plant influence on pest development and reproduction. Certain rootstocks supported faster development, higher survival rates, and increased fecundity, suggesting greater susceptibility to scale infestation. In contrast, resistant rootstocks exhibited prolonged developmental periods, reduced nymphal survival, and lower reproductive output. Age-specific survival and fecundity curves demonstrated reduced population growth potential on resistant genotypes. Demographic analysis showed significant differences in key population parameters, including net reproductive rate (R₀), intrinsic rate of increase (r), finite rate of increase (λ), and mean generation time (T) among rootstocks. Rootstocks with adverse effects on pest biology resulted in slower population growth and reduced infestation potential. The study highlights the critical role of host plant resistance in regulating A. aurantii population dynamics. Overall, the findings demonstrate that selection of suitable citrus rootstocks can significantly influence pest biology and contribute to sustainable management strategies. These results provide valuable insights for integrating host plant resistance into citrus pest management programs aimed at reducing reliance on chemical control measures.