Abstract
These studies were carried out to investigate the bionomics of Gonatocerus sp. y (Hymenoptera: Mymaridae) , an egg parasite of the green rice leafhopper, Nephotettix cincticeps Uhler (Homoptera: Deltocephalidae) under laboratory and field conditions at Gyeongnam Provincial O.R.D. in Jinju from 1982 to 1983. The developmental period of each life stage was observed under four different temperature conditions from $15^{\circ}C\;to\;30^{\circ}C\;with\;5^{\circ}C$ increment. The development from egg to adult at 15^{\circ}C,\;20^{\circ}C,\;25^{\circ}C,\;and\;30^{\circ}C $ was completed in an average of 53, 25, 15, and 12 days and the females laid an average of 28, 48, 42, and 32 eggs respectively, with a maximum of 98. And most of the eggs were laid in the first two days after emergence. The time of adult emergence was determined under $25{\pm}1^{\circ}C$ condition. More than $76\%$ of the wasps emerged in the morning and the rest of them emerged in the afternoon. The average sex ratio between male and female was 1 : 5 when the wasps were developed from fertilized eggs. The longevity of female was greater than that of male when honey and water were provided as food, however, it was not when only water was supplied as food. The average longevities of females were 30 days at $15^{\circ}C$ and 15 days at $20^{\circ}C$ when honey and water were given as food. The peak precent parasitism of Gonatocerus sp. v on Nephotettix cincticeps in fallow fields was observed between late April and early May. The percent parasitism of the wasps In fallow fields was an average of 49\~59.9\% $ in Gyeochang, Namji and $23.2\~36\%$ in Namhae. The parasitic activities of the parasite had four peaks in paddy field, however, the highest peak was observed between late August and early September. The Percent e99 Parasitism of Gonatocerus sp. y was an average of $12.3\%$ on second the generation and $24.6\%$ of third genera lion of Nephotettix cinrticeps.
본 연구는 1982연과 1983년 끝동매미충의 난기생봉중에 우종인 Gonatocerus sp. y의 생태를 실내와 포장에서 수행하였으며 그 결과는 다음과 같다. 1. Gonatocerus sp. y의 난에서 성충으로 우화되기까지 평균발육기간은 $15^{\circ}C,\;20^{\circ}C,\;25^{\circ}C$ 및 $30^{\circ}C$에서 각각 53일, 25일, 15일 및 12일이였다. 2. 성충의 평균 산란수는 $15^{\circ}C,\;20^{\circ}C,\;25^{\circ}C$및 $30^{\circ}C$에서 각각 28개, 48개, 42개 및 32개였고 산란기간은 대부분 $1\~2$일 이내였으며 최고 산란수는 98개였다. 3. 성충의 우화는 전체의 $76\%$가 아침에 이루어 졌으며 오후에는 거의 우화하지 않았다. 4. 성충의 우화성비는 암수의 비율이 4 : 1인 것이 가장 많았다. 5. 성충의 수명은 물보다 꿀물을 먹이로 주었을 때가 현저히 길어졌으며 수컷보다 암컷이 다소 길어졌다. 그리고 꿀물을 주었을 때 암컷의 평균 수명은 $15^{\circ}C$에서 30일, $20^{\circ}C$에서 15일이였다. 6. 휴한답의 둑새풀에 산란된 끝동매미충 난에 대한 시기별 Gonatocerus sp. y의 기생율은 4월 하순에서 5월 상순에 가장 높았다. 7. 휴한답에 있어서 4월 하순부터 5월 상순 사이에 지역별로 조사한 본 난기생봉의 기생율은 거창, 남지, 진주지방에서 $49.0\~59.5\%$, 남해, 김해지역에서 $23.2\~26.0\% $였다. 8. 본답기에 있어서 끝동매미충의 2세대충(6월 하순경발생)과 3세대충(8월 하순경 발생)에 대한 본 난기생봉의 기생율은 각각 $12.3\%$와 $24.6\%$였다.