Abstract
The chestnut gall wasp, Dryocosmus kuriphilus $Y^{ASUMATSU}$, has been recently distributed and chestnut trees have teen seriously damaged by this insects in Korea. However, this insect pest has not been investigated in Korea. This paper gives an account of field and Laboratory observations on the seasonal occurrence and the life history of the chestnut gall wasp, and the damage of the chestnut trees by. its insects. This study was carried out at Chungchungpukdo, Kangwon-do and Kyungi-do in Korea, from 1961 to 1963, inclusive. 1. The Chestnut gall wasp (Dryocosmus kuriphilus $Y^{ASUMATSU}$) has one generathion per year and females are only known. 2. The adult wasps were observed from late June to late July with peak of wasp emergence about early and middle July. Most of new adult wasps were coming out from, the galls in the morning rather than the afternoon. 3. Each wasp produced auerage 198.5 eggs and about 4.89 eggs was observed in each bud of the chestnut tree. 4, The egg period of wasps was about 30 days and they were hatching from July to August. 5. The larval period of wasps were from middle of August to middle of next June and pupation took places about early June to middle of July. 6. The adult wasps were ovipositing into the buds and from early May next year, galls were growing. They caused stunting of growth and no fruiting or dying of the chestnut tries. 7. The first observation of the wasp was made at Chaechun of Chungchung-pukdo in 1958. Up to 1963 this insects are distributed in Kangwon-do, Kyunggi-do, north part of Chungchung-pukdo and north part of Kyungsangpukdo
본 조사는 밤나무혹벌의 생태, 특히 생활사, 발생소장 및 피해에 대하여 1961-1963년에 걸쳐 경기도, 강원도 및 충청북도에서 조사한 것이다. 1. 본 충은 년 1회 발생하며 단성생식을 한다. 2. 성충의 출현은 6월 하순부터 7월 하순이며 최성기는 7월중하순이며 일중 오전중에 많이 탈출한다. 3. 성충은 출현후 곧 아에 산란하는데 1아당 4.89개를 산란하며 1개체의 포란수는 평균 198.5개이었다. 4. 란기는 30일간이며 란은 8월말까지 부화하였다. 5. 유충기간은 8월중순부터 익년 6월 중순 까지며 용기는 6월 초순부터 7월 중순까지였다. 6. 본 충은 아에 산란 기생하며 5월 하순부터 충영을 형성하여 생장을 정지시키고 율의 결실을 없게 할 뿐만 아니라 율목을 고사시킨다. 8. 본 충은 1958년 충청북도 제천에서 처음 발생된 이래 현재에는 강원도, 경기도, 충청북도의 북반부 및 경상북도북부 일부에 분포하여 가해하고 있다.