| There were rich forest resources in the northwest of fujian province. the industry in these areas demand much more wood; on the other hand, protecting the forest resources in these areas was very important to the envirment. Populus Planting were good to economy and ecology. In order to alleviating the contradiction between industrial demands for wood and envirment protection,the northwest of fujian province have introduced Populus in large area. At present, A.germari(Hope) has become a new pest of Populus in northwest of Fujian province. The research mainly studied its biological and ecological characteristics by systemic investigation and observation to grope for the phylogeny and provide advisable directions for the pest population prevention and forcast.1 A.germari biological characteristicsA.germari has 1 generation in 2 years in Fujian province. The elder larvae began to pupate in April and May. Emergence of adult occur in the last ten days of May, the adult stage could last for four monthes, The female began to laid eggs in the middle of june.larvae occured from the middle of june, to minddle of August.A.germari mainly feed on Morus alba and Broussonetia papyrifera. Feeded on Populus, the life-span of adults were just 3-19 days; on the other hand, feeded on Morus alba, the female life-span were 55 days, the male were 26．5 days; feeded on Broussonetia papyrifera, the female life-span were 78 days, the male were 45．5 days. The adults could mate multi-time each other in all life. During the laying season, the female adults ususlly laid eggs in many times, and each time a female adult could produce 1～12 eggs.2 A.germari ecological characteristicsBy use of the aggregation indexes method, regressive model analysis method and zero frequency, thespatial distribution patterns of A.germari larvae were studied. The results led to estimate the assembledistribution type for larvae in the forest.The basic distribution component was individual colony. Within eachcolony, the individuals attracted each other. According to the zero frequency method, the A.germaripopulation belonged to "zero frequency dependent" type. Otherwise, the optimal theoretical sampling numberof the larva and the sequential sampling model were obtained. By use of the Geostatistical methods, the spatial patterns of A.germeri larvae in the field were studied, the result showed that the semivariogram could be perfectly described by spherical model.The spatial pattern was conferred to the assemble distribution type.The populational dependence range of A.germeri larvae was 12～13m,The larvae spot was not rotundity, analysising on the parameters of semivariogram at different grid size,the result showed that there was a close relation between the sill and the grid side.The paper deals with the threshold temperature for development and effective cumulative temperature of A.germeri egg, The results showed that the threshold temperatures was 14．89±1．85℃, and The effective cumulative temperatures was 163．60±30．15℃/d.3 The control test on A.germariThe field application of three chemical pesticides in diffirent ways to control A.germari larvae was conucted. the results shows that injestion and poison tampon were effective ways to control A.germari larvae.The control effect could reach 71．44～97．54% after 15 days.The pathogenicity of seven Metarhizium against A.germeri larvae was bioassayed in laboratory. The results indicated that the cadaver rates of the seven strains of Metarhizium were at 25 %～40 %, the strain MA 1775, the rate was the best, as high as 40 %.
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