Thermal Biology and Age-Specific Fertility Table of Aphis nerii (Hemiptera: Aphididae) on Ornamental Nerium oleander

Abstract

Thermal biology and age-specific fertility table of Aphis nerii (Hemiptera: Aphididae) on ornamental Nerium oleander were investigated to understand its developmental performance, reproductive potential, and population growth under varying temperature conditions. Laboratory experiments were conducted at different constant temperatures using potted N. oleander plants, and developmental duration, survival rate, fecundity, and longevity were recorded across life stages. Results indicated that temperature significantly influenced the biological performance of A. nerii, with moderate temperatures supporting optimal development, higher survival, and increased reproductive output. At lower temperatures, developmental rates were prolonged and fecundity reduced, while excessively high temperatures negatively affected survival and adult longevity. Age-specific fertility table analysis revealed marked differences in survival probability, age-specific fecundity, and net reproductive rate across temperature regimes. The intrinsic rate of increase and finite rate of population growth were highest under optimal thermal conditions, indicating rapid population buildup potential. Life expectancy decreased progressively with age, and reproductive contribution was concentrated in early adult stages. Thermal thresholds determined in the study highlight the species’ adaptability to ornamental plant environments across varying climatic conditions. The study emphasizes the strong influence of temperature on population dynamics of A. nerii and its potential for rapid outbreaks in ornamental landscapes. These findings provide valuable insights for predicting pest population trends and developing temperature-based forecasting models for integrated pest management in Nerium oleander cultivation systems.