The oviposition and host-feeding behaviors of Encarsia smithi (Silvestri) (Hymenoptera: Aphelinidae) on a tea-infesting population of Aleurocanthus spiniferus (Quaintance) (Homoptera: Aleyrodidae) were observed under laboratory conditions. The following events were recorded for the host-searching and oviposition behaviors of E. smithi: 1) random walking, 2) walking while drumming, 3) drumming on the host after encountering it, 4) turning backward and everting the ovipositor, 5) inserting the ovipositor, 6) liquid flowing inside the ovipositor, 7) adopting the ovipositioning posture while standing still, and 8) cleaning the ovipositor with the hind legs. Host-feeding behavior was observed after turning backward and everting the ovipositor. The following events were recorded for the host-feeding behavior of E. smithi: 1) repeatedly inserting and withdrawing the ovipositor, 2) turning forward, 3) searching for the wound in the host, and 4) feeding on the host's fluids. Each adult female wasp deposited an average of 67.6 eggs and killed an average of 14.0 hosts by host feeding. In addition, the mean oviposition time of E. smithi was 1,682.7 s, which is markedly longer than that reported for congeneric species.

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Successful rearing of Stenotus rubrovittatus, known to cause pecky rice, is complicated by the fact that adult females only oviposit into the spikelets of gramineous plants in nature. In this study, methods for rearing and collecting S. rubrovittatus nymphs using early wheat seedlings were investigated. Females were observed to oviposit their eggs into the coleoptile shortly after the appearance of the first foliage leaf from the coleoptile sheath (3 d after seeding). Nymph emergence from stem cuttings incubated on moist filter paper in a Petri dish was more than five times higher than it was from whole seedlings. Seventy two hours after oviposition, more than half of the eggs oviposited on the whole seedlings appeared on the outer surfaces of leaves following leaf elongation; these eggs did not hatch. The rate of emergence from eggs removed from the inner surfaces of leaves and incubated in Petri dishes was 86.7% at a relative humidity (RH) of 100%, decreasing markedly when RH ≦97%. These findings implied that eggs which became exposed outside the sheaths would not hatch due to desiccation. Conversely, egg-feeding by adults was not considered to have a negative effect on the hatching rates of exposed eggs. However, when the duration of seedling exposure increased, egg-feeding by adults resulted in increased egg losses. In addition, an overall increase in adult densities resulted in a decrease in nymphal emergence per female. Consequently, the number of hatching nymphs could be increased by storing the stem cuttings of wheat seedlings on moist filter paper in Petri dishes following adult oviposition, ensuring that the densities of adults were maintained at the optimal level of 30 pairs of males and females per 100 seedlings, and by replacing wheat seedlings at 24 h intervals.

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The white peach scale, Pseudaulacaspis pentagona (Targioni), is one of the most important pests infesting tea trees in Japan. We investigated the susceptibility of populations of the insect collected from tea fields in Shizuoka and Miyazaki prefectures against five insecticides, methidathion, isoxathion, buprofezin, fenpyroximate alone and a fenpyroximate- buprofezin mixture. The susceptibility was evaluated by spraying the pesticides on first instar larvae on tea branches. The corrected mortality of Shizuoka populations after treatment with 200 ppm buprofezin was less than 21.7%, indicating a high resistance to buprofezin. The LC₅₀ of methidathion varied from 26.8 ppm (Miyazaki population) to 773.0 ppm (Yui population in Shizuoka), and thus resistance to methidathion was also suggested; however, Shizuoka populations were susceptible to both fenpyroximate treatments, as were the Miyazaki populations.

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The seasonal occurrence of Neoseiulus womersleyi and Tetranychus urticae in apple orchards that received pyrethroid applications was investigated from 2006 to 2007 in Akita Prefecture, northern Japan. The density of N. womersleyi increased continuously during the summer in response to the density of T. urticae, even in pyrethroidtreated plots. The susceptibility of six strains of N. womersleyi was examined against nine pyrethroid insecticides. The mortality of females of the six strains of N. womersleyi was less than 30% in most insecticides tested. These results suggested that pesticide-resistant N. womersleyi occurred in commercial apple orchards, which is promising for the control of T. urticae in the apple IPM program.

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