Studies on the Effects of Systematic Applications of Several Insecticides on the Population of the Brown Planthopper, Nilaparvata lugens Stål : Ⅰ. Effects of Some Systemic Insecticides on the Early Population
벼의 초기(初期) 발생해충군(發生害蟲群)의 방제(防除)를 위(爲)하여 쓰이고 있는 몇가지 침투성(浸透性) 살충제(殺蟲劑)의 초기(初期) 비래(飛來) 벼멸구에 대(對)한 방제효과(防除效果)를 평가(評價)하기 위하여 carbofuran(3G)과 disyston(3G)를 이앙직전(移秧直前)(5월(月) 27일(日)) 토중혼입(土中混入)과 수면시용(水面施用)하였고, omethoate 50% EC는 이앙(移秧) 6일후(日後)에 엽면산포(葉面散布)한 다음 6월(月) 11일(日), 21일(日), 7월(月) 2일(日), 11일(日), 25일(6月 11日, 21日, 7月 2日, 11日, 25에 pot당(當) 벼멸구를를 10쌍식(雙式) 접종(接種)하고 10일후(日後)부터 벼멸구의 밀도(密度)를 조사(調査)하였다. 최종밀도(最終密度)를 기준(基準)으로 생각할 때 산포후(散布後) 약(約) 10일경(日頃)까지는 모든 처리구(處理區)에서 엽효(葉效)가 인정(認定)되었으나 그 이후(以後)에는 carbofuran 처리구(處理區) 이외(以外)에서는 효과(效果)를 인정(認定)할 수 없었다. carbofuran처리구(處理區)에서는 수면시용(水面施用)에 비(比)하여 토중혼입구(土中混入區)에서 약효지속기간(藥效持續期間)이 약(約) 일간(日間) 지속(持續)되어 6월중순(月中旬)하순(下旬)까지 비래(飛來)하는 벼멸구에 대(對)한 밀도억제효과(密度抑制效果)를 기대(期待)할 수 있을 것으로 사료(思料)된다.
The control effect of three systemic insecticides on the brown planthopper, carbofuran 3G, disyston 3G, and omethoate 50% EC, which have been used to control of the insect pests on rice crop in its early growing season, were evaluated. Soil incorporation and water broadcasting methods before transplanation were used for carbofuran and disyston, and omethoate was applied as foliar spray 6 days after transplanation. Ten pairs of newly emerged adults were inoculated on June 11, 21, July 2, 11, and 25. The number of the brown planthoppers on the rice plane were examined by means of direct reading. The three insecticides were effective for about ten days regardless of application methods, thereafter, fail to control of the insects except carbofuran. By means of soil incorporation, carbofuran could control the insects effectively for 45 days or longer, and it seemed to be able to control the progeny of the migrated brown planthopper until middle or late June.