Metcalfa pruinosa was first reported in 2009 in Gimhae persimmon farms in Korea, and in Chungnam province in 2011, they first occurred in Dangjin and Taean. M. pruinosa adults are known to lay eggs among the crevices beneath the bark of the host plants, and they are reported to lay mainly on Robinia pseuroacacia trees. However, in order to solve the problem that the time and effort are too much to investigate by moving the 10 cm branch of R. pseudoacacia and removing the whole bark, we investigated the number of wintering eggs at different parts of branches from R. pseudoacacia and surveyed occurrence of them in Chungnam province. 14.5 times and 5.4 times more eggs were observed in the hair tissues of the twigs and thorms bases than the surface of R. pseudoacacia trees, respectively. There was no difference in the number of branches according to the thickness of branches. M. pruinosa in Chungnam province were mainly occurred in Taean, Geumsan and Dangjin, and showed patterns that occurred mainly in highways.

Developmental time, mummification, pupal mortality, sex ratio of a South Korean strain of Aphelinus varipes Förster parasitizing the green peach aphid, Myzus persicae were studied at 20, 25 and 30℃ in controlled climate cabinets. Plastic container with sweet pepper(Capsicum annuum L.) were used as experimental units. Green peach aphid in different larval instars and as adults, reared at the three different temperatures, were presented to A. varipes in a 'no-choice' and 'choice' situation for 6h. These presentations were done at 25℃ in each experiment to avoid an influence of temperature on parasitization rate. In case of no-choice test, more 1st(24%), 2nd(22%) and 3rd(38%) instar aphids were parasitized than 4th(14%) instar and adult(10%) among the aphids reared at 25℃. In case of choice test, more 1st(41%), 2nd(42%) and 3rd(29%) instar aphids were parasitized than 4th(13%) instar and adult(0%) among the aphids reared at 25℃. Pupal mortality of the parasitoid was not influenced by temperatures. The sex ratio of A. varipes was male-biased, and varied between 49.4% females developed from aphids reared at 30℃ and 42.8% from aphids reared at 20℃. The sex ratio was not significantly influenced by host stages. The developmental time of A. varipes parasitizing the green peach aphid ranged from 26.1days at 20℃ to 11.1days at 30℃.