Abstract: Insect infestation and its effects on acorn fate in Quercus liaotungensis was studied in Beijing in 1998～1999. The results showed that insect infestation influenced strongly acorn germination rate: insect-infested acorns exhibited a lower germination rate than that of noninfested ones. The infested acorns could not germinate or died eventually after germination. Seed parasitoids, two weevils, Curculio dentipes and Curculio sp., a tortricid moth, Cydia kurokoi, and an unnamed pyralid moth, developed within acorns from eggs to advanced larvae. These larvae penetrated the hard seed wall and came to hibernate under ground after acorns fell down. Of all acorns within a population, the penetrating time was not synchronized and ranged from 2 to 50 days. The infested rate of acorns was as high as 45.41%. Insect parasitism was shown to have an influence on acorn growth and development: the size-pattern of infested acorns was between that of noninfested mature ones and that of immature ones; infested acorns lost 16.05% of their fresh weight compared to those that developed normally. Based on this study, it is concluded that insect infestation decided to a great deal the fate of Quercus liaotungensis acorns and would strongly influence its regeneration.

Key words: Quercus liaotungensis, acorns, insect infestation, Curculio dentipes, Cydia kurokoi