Life histories of three predatory mites feeding upon Carpoglyphus lactis (Acari, Phytoseiidae; Carpoglyphidae)

The phytoseiid mites, Amblyseius swirskii (Athias-Henriot) and Neoseiulus cucumeris (Oudemans) are important biological control agents introduced from outside of China. On the other hand, Amblyseius eharai Amitai & Swirski that is native to China and Japan is considered to be an effective natural enemy in China citrus orchards and bamboo forests. In order to develop effective mass production of these three species, the life history parameters, net reproductive rates (R-0 /female), and intrinsic rates of increase (r(m) /day) of the three species, A. swirskii (Athias-Henriot) and N. cucumeris (Oudemans), were observed under experimental conditions (25 +/- 1 degrees C, 90 +/- 5% RH and L:D = 14:10 h) with Carpoglyphus lactis (Linnaeus) produced by dry yeast. All species could normally develop and reproduce with C. lactis. The mean developmental period of A. swirskii females was the longest and was different from the other two species. The mean oviposition period and the fecundity of the three predatory species did not differ. The mean longevities of A. swirskii and A. eharai were shorter than that of N. cucumeris. The total fecundity among the three predatory species was not significantly different. Although no differences in R-0 were found among the three predators, the r(m) of A. swirskii was lower than that of A. eharai because of its long mean generation time (T). Additionally, the r(m) of N. cucumeris was the lowest among the three predators because it had the longest T. As such we established C. lactis as a suitable extra-guild prey species for A. eharai, A. swirskii and N. cucumeris in a comparison with previous reports that tested various food types, such as pollen, insects and mites. This study is the first to report that C. lactis was prey for A. eharai and N. cucumeris. Populations of C. lactis increased easily with dry yeast, and thus, this prey was very suitable for the present experiments.