Synergistic effects of pollen grains on several vital life parameters of Amblyseius swirskii when preying upon Tetranychus urticae.

In this study, the efficiency of two pollens, Bird-of-paradise and Damask rose, was evaluated concerning the life table of the phyto-carnivorous predator Amblyseius swirskii, both alone and in combination with the spider mite Tetranychus urticae as a natural prey. Results showed that feeding on these pollens significantly increased fecundity and extended the oviposition period (40.29 eggs in 27.4 days, and 35.82 eggs in 21.41 days, respectively) compared to the prey alone (27.20 eggs in 18.40 days). The significantly highest pre-adult duration (6.714 days), adult longevity (71.45 days), fecundity (92.16 eggs/female), and oviposition days (50.3 days) were recorded in the treatment involving Bird-of-paradise + spider mite. The gross (GRR) and net (R0) reproductive rates in both Damask rose + spider mite (41.99 and 36.49 eggs/individuals) and Bird-of-paradise + spider mite (51.7 and 46.9 eggs/individuals) indicated the highest values, with no significant difference between the two treatments. The significantly highest intrinsic rate (r = 0.179 day-1) and finite rate of increase (λ = 0.157 day-1) were measured in the treatment of Bird-of-paradise + spider mite. Therefore, the examined pollens induced A. swirskii to reproduce significantly for a longer duration. Additionally, each pollen, when mixed with the prey demonstrated additive effects on oviposition and population growth.