The chemical control of the Biting Midge,Forcipomyia(Lasiohelea)taiwana(Shiraki)(Diptera:ceratopoonidae at Nantou area)

台灣鋏蠓 [Forcipomyia(Lasiohelea)taiwana (Shiraki)]之分布遍及本省各地，散布在台北縣、宜蘭縣、桃園縣、新竹縣、彰化縣、雲林縣、南投縣、台中縣、嘉義縣、台南縣、花蓮縣、高雄縣等12縣之鄉鎮中危害，危害的範圍涵蓋整個台灣。台灣鋏蠓成蟲的室內藥劑試驗以除蟲菊精為有效成分的商品藥劑，所產生的擊昏效果比以有機磷為有效成分的商品藥劑佳，在幼蟲試驗方面，因在實驗室中藥劑都能有效的接觸到蟲體，所以都有致死效果，藥劑間並無差異。在卵和蛹的試驗方面，是以有效成分中含有有機磷的 Chlorpyrifos 或 Primiphos-methyl藥劑成分者其致死率較高。 在田間實施冬季藥劑防治，於中寮鄉的中寮社區、中寮國中、爽文村、竹山鎮的溪洲子、富州里、集集鎮的樂園里、隘寮社區、隘寮國小等試驗區的試驗結果，春季確能延滯台灣鋏蠓族群的增長，且在危害較嚴重的６、７、８月間，使族群密度不致於遽增，仍可維持較低的蟲數。但在鹿谷鄉的瑞田國小因受茶園無法施藥的影響，施用藥劑無法涵蓋整個防治區，而無法有效抑制台灣鋏蠓密度。在秀峰村也因為以生長調節劑(IGR)作為幼蟲防治的藥劑效果不佳，造成了７月之後台灣鋏蠓的族群密度急速增加。 冬季化學防治使用生長調節劑防治台灣鋏蠓幼蟲的成效較差，而使用熱霧機和超低容量噴灑法防治台灣鋏蠓成蟲的成效並無差異性，二者皆有極佳的成效，若能有效找尋到台灣鋏蠓棲息孳生的場所，加以施藥就能得到較佳的防治效果。The biting midge, Forcipomyia (Lasiohelea) taiwana (Shiraki), spreads all over Taiwan, except Keelung, Miauli, Pintong and Taitong, causing affliction in areas such as Taipei county, I-lan county, Taoyuan county, Hsinchu county, Changhua county, Yunlin county, Nantou county, Taichung county, Chiayi county, Tainan county, Hualien county and Koushiung county. For the chemical control of adult in the laboratory, pyrethrin was found to be more efficient than organophosphate in its knock-down effect. For the larva control, because all of the chemicals tested in the laboratory could contact the larvae so they all proved to be effective in killing. As for the egg and pupa control, the chemicals containing Chlorpyrifos or Primiphos-methyl had more lethal effect. In the winter, the administration of chemical control in field could delay the population growth of F. taiwana in the following spring and thus inhibited the outbreak of the population during June, July and August. In Nantou areas where such administration were undertaken included Chungliao community, Chungliao junior high school, Swangwen village, Shijoutzy in Chunshan country, Fuhjou alley, Leryuan in Chichi country, Ailiao community, Ailiao elementary school. However, the chemical control was less successful in Rueytian elementary school because the chemicals were not able to cover the whole intended area due to the existence of tea farms. At Shioufeng village, the outbreak of F. taiwana occurred after July because IGR was not effective in larvae control. As for the effectiveness of different administration methods of chemical control in the winter, IGR to larvae was less efficient than other organophosphate chemicals. Fog and ULV application to control adults are effective. If the breeding sites of F. taiwana could be located and sprayed with effective chemicals, a more effective control could be achieved