Studies on bionomics and occurrence regulation ofPhigalia djakonovi Moltrecht

Investigation and observation were made on bionomics and occurrence regulation ofPhigalia djakonovi Moltrecht, which is a major pest of white birch, in Daxing’an Mountain forest area of Inner Mongolia during 1997 to 1999. The pest has one generation per year and overwinters as pupae in the soil in this area. Development, bionomics and outbreak of the pest are closely related with the food and environment conditions. Foundation item: This paper is a part of Key Subject of Birch in State 9th Five-Year Plan Biography: W{upang} Ya-qin (1966-), female, engineer in Yakeshi Forestry Administration. Inner Mongolia. P. R. China. Responsible editor: Chai Ruihai