Influence of Prey Consumption on the Predatory Potential andBiological Parameters of Exochomus nigripennis (Erichson) AgainstPhenacoccus solenopsis Tinsley and Icerya seychellarum (Westwood)

Phenacoccus solenopsis Tinsley and Icerya seychellarum (Westwood) are recent invasive sap-sucking insects in Egypt. Exochomus nigripennis (Erichson) being a viable option for conventional biological control. In the laboratory of the Plant Protection Research Institute, Agricultural Research Centre, Egypt, the biological parameters and predatory potential of E. nigripennis were assessed using P. solenopsis and I. seychellarum as preys. Fourth instar E. nigripennis larvae was recorded the highest average total consumption of 455 individuals, with a feeding capacity of 43.10 when reared on P. solenopsis. While the third larval instar of E. nigripennis consumed the maximum number of I. Seychellarum 43.11 with a feeding capacity of 45.18 compared to other instars. E. nigripennis females had a lifespan of 30.9 ± 1.21 days, and consuming 3255 preys on P. solenopsis, while males had a feeding capacity of 2198.64. The immature stages of E. nigripennis varied significantly based on the prey species. Larvae developed faster on I. Seychellarum, while pupal periods were shortest on I. Seychellarum and longest on P. solenopsis. The shortest development time was on I. Seychellarum (22.8 days), while the longest was on P. solenopsis (30.37 days). The longevity and reproduction of E. nigripennis were significantly influenced by the preys they were reared on. Males and females fed on P. solenopsis exhibited longer survival and females had an extended oviposition period. The fecundity was highest when females were fed P. solenopsis supplemented with sugar solution. The study suggests that an integrated pest management program can effectively manage P. solenopsis and I. seychellarum, by utilizing E. nigripennis as a biological control agent, making it suitable for mass rearing in agricultural ecosystems.