Quality control of the predatory mite Amblyseius swirskii during long-term rearing on almond Prunus amygdalus pollen

The predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) is a commercially available natural enemy of phytophagous mites and insects. The current study tested the utility of plant pollen as a non-prey diet for mass rearing A. swirskii. Experiments tested the effects of almond Prunus amygdalus Batsch pollen on biological parameters and population growth of A. swirskii from the 1st to the 45th generation (G1-G45) and predation of Tetranychus urticae Koch (Acari: Tetranychidae) before the 1st generation (B-G1) and after the 45th generation (A-G45). Results indicated that the intrinsic rate of increase (r) and finite rate of increase (lambda) were lowest in G1 and G3 and both increased and reached their highest values in G20, then decreased slightly and remained constant from G25 to G45. Comparison of the performance of A. swirskii between B-G1 and A-G45 indicated that pre-imaginal duration time was significantly longer for B-G1 than for A-G45. Total pre-oviposition period and oviposition days were significantly longer for B-G1 than for A-G45. Adult longevity was greater for A-G45 than B-G1. Furthermore, life table parameters R-0, r, and lambda were significantly higher for A-G45 than for B-G1. Finally, net predation rate (C-0), transformation rate (Q(p)), and finite predation rate (omega) were significantly higher for A-G45 than for B-G1. Overall, the results of this study suggest that almond pollen is suitable for long-term rearing of A. swirskii. Almond pollen may enhance A. swirskii predation capacity but further experiments on infested whole plants are necessary to confirm the results reported herein.

Automated summary

The study found that almond pollen is suitable for long-term rearing of the predatory mite Amblyseius swirskii and may enhance its predation capacity. Further experiments on infested whole plants are necessary to confirm the results.