Functional response and biological characteristics of Orius vicinus (Ribaut) (Hemiptera: Anthocoridae) on Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae)

Abstract This study evaluated the functional response and life table parameters of the predator Orius vicinus (Ribaut) (Hemiptera: Anthocoridae) when fed on immature stages of the polyphagous pest Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae). Biological and life table parameters, including development, survival, reproduction, and population growth rates, were assessed using two-sex age–stage life table analysis. Functional responses of adult O. vicinus to the egg, larval, and pupal stages of B. tabaci were determined separately under controlled conditions of 26 ± 1 °C, 60 ± 10% relative humidity (RH), and a 16:8 h light: dark (L: D) photoperiod. Results showed that egg development lasted 4.67 ± 0.06 days, total nymphal development was 13.65 ± 0.13 days with a survival rate of 77.32%, and mean fecundity per female was 60.89 ± 2.76 eggs. Female and male adult longevities were 16.95 ± 0.55 and 12.27 ± 0.54 days, respectively. Adult preoviposition period (APOP) and total preoviposition period (TPOP) were 4.14 ± 0.12 and 22.7 ± 0.23 days, respectively, while the oviposition period lasted 11.23 ± 0.53daysThe estimated life table parameters were the intrinsic rate of increase ( r ) of 0.113 day⁻¹, the net reproductive rate ( R 0 ) of 24.8 offspring, the finite rate of increase ( λ ) of 1.12 day⁻¹, and the mean generation time ( T ) of 28.4 days. Functional response analysis revealed a Type III response to eggs and larval stages, and a Type II response to pupae. These results indicate that O. vicinus could be effectively integrated into Biological control programs against B. tabaci .