The toxicity of 85 insecticides, 20 acaricides, 70 fungicides, and 15 spreaders was tested against the predatory mite, Neoseiulus californicus（McGregor）（Acari: Phytoseiidae）. Four neonicotinoids, 1 sulfoximine, 2 pyridine azomethine derivatives, 2 Bacillus thuringiensis and the insecticidal proteins they produce, 6 benzoylureas, 1 buprofezin, 3 diacylhydrazines, 1 oxadiazine, 1 semicarbazone, 6 diamides, flonicamid, pyridalyl, flometoquin, 9 acaricides, 4 spiracle-blocking insecticides, 52 fungicides, and 13 spreaders were harmless to the survival of adult females and immature individuals. These pesticides had little effect on the survival of adult females but 2 neonicotinoids, 1 semicarbazone, flometoquin, 3 acaricides, 2 spiracle-blocking insecticides, 11 fungicides, and 4 spreaders reduced the fecundity. The residual toxicity of 7 insecticides, 6 acaricides, and 5 fungicides were examined against the adult females. These pesticides could be divided into 3 groups: Group A（materials that were harmful as less than 14-day-old residues）: fenitrothion, imidacloprid, spinosad, spinetoram, emamectin, milbemectin, bifenazate, and pyflubumide＋ fenpyroximate, Group B（materials that were harmful as 14- to 21-day-old residues）: thiamethoxam, spirotetramat, etoxazole, propineb, mancozeb, and chinomethionat, and Group C（materials that were harmful as 21- to 28-day-old residues）: amitraz, pyridaben, thiophanate-methyl, and diethofencarb＋thiophanate-methyl.

The effects of insecticides on arrhenotokous and thelytokous types in adult females of onion thrips, Thrips tabaci Lindeman, collected from a total of 13 sites of Welsh onions, cabbages, and onions in Kyoto Prefecture, Japan, in 2016 and 2017 were evaluated. Susceptibility to the tested insecticides varied among the reproductive types, populations, and years. Among the 14 insecticides tested on female adults in arrhenotokous type using the kidney bean leaf dipping method, spinetoram, spinosad, avermectin, cyantraniliprole, fluxametamide, and flometoquin were the most toxic. In addition, cypermethrin, imidacloprid, spinetoram, spinosad, avermectin, cyantraniliprole, fluxametamide, and flometoquin caused a high mortality rate in female adults in thelytokous type. Overall, the mortality rate in thelytokous type was higher than that in arrhenotokous type.

To examine the effects of groundcover preservation around tree trunks in Japanese pear orchards on the seasonal occurrences of spider mites and their natural enemies, we compared their densities at two study sites, each of which includes two plots with weeds（weed plot）and without weeds（control plot）, in Chiba Prefecture in 2016 and 2017. The phytoseiid mites were the most dominant natural enemies observed on the trees. The densities of phytoseiid mites and spider mites on the trees were, respectively, higher and lower in the weed plots than in the control plots. The mean density of yellow tea thrips, Scirtothrips dorsalis Hood, on the trees was also higher in the weed plots than in the control plots. Some phytoseiid mite species were commonly observed on both groundcover around the tree trunks and pear trees throughout the survey period, suggesting contributions of the phytoseiid mites supplied from the groundcover in spider mite control on the pear trees.