Predatory potential against Thrips palmi Karny of some native phytoseiid mites (Acari: Phytoseiidae) occurring on greenhouse vegetable crops in Kochi prefecture, Japan.

Abstract

We investigated the prey consumption and oviposition rates of six native phytoseiid mites, Neoseiulus barkeri Hughes, Euseius sojaensis (Ehara), Amblyseius tsugawai Ehara, Proprioseiopsis memotoi (Ehara and Amano), Gynaeseius liturivorus (Ehara) and A. eharai Amitai and Swirski, occurring in greenhouses in Kochi prefecture. These values were compared with those of N. cucumeris Oudemans, a commercial biological control agent. First instar larvae of Thrips palmi Karny were provided as prey for predacious mites. The results showed that G. liturivorus exhibited excellent prey consumption and oviposition rates as 12.2 larvae/day and 6.5 eggs/day, respectively, whereas those of N. cucumeris were 3.9 larvae/day and 2.2 eggs/day, respectively. A. eharai also showed a higher prey consumption rate (5.8 larvae/day) than N. cucumeris. Four other native phytoseiid species also consumed T. palmi larvae, but the prey consumption and oviposition rates were lower than N. cucumeris. In conclusion, both G. liturivorus and A. eharai were considered as promising candidates for biological control agents of T. palmi. E-mail: kazuhiro_komi@ken2.pref.kochi.lg.jp