Study on the ecology and control of cycad scale, Aulacaspis yasumatsui Takagi (Homoptera: Diaspididae)

蘇鐵是國內重要的園藝觀賞作物，近年來受到新侵入害蟲蘇鐵白輪盾介殼蟲( Aulacaspis yasumatsui Takagi , 1977 ）的嚴重危害，造成公園、學校、機關、栽培園的蘇鐵大量死亡。蘇鐵白輪盾介殼蟲繁殖力強，為害範圍遍及全株，尤其可深入植株莖部鱗片深處及地下的根部棲息，防治極為困難。加上本蟲在台灣出現的時間很短，基礎生物與生態學研究資料相當缺乏，使得相關單位對該蟲的為害一籌莫展。本文以該蟲的入侵分散、診斷鑑定、生活史及族群動態調查、殺蟲藥劑篩選、本土天敵調查、輻射檢疫處理、緊急防治處理及杜絕該蟲蔓延保護區的標準操作程序等項目進行研究，期能有助於進行蘇鐵白輪盾介殼蟲的綜合防治。 Since 2000, heavy infestations of a scale insect, Aulacaspis yasumatsui Takagi, have been discovered on cycad, an important ornamental plant in Taiwan. A large number of cycads were found dead in parks, schools, building grounds, and gardens, resulting from its damage. A. yasumatsui known to have a high reproductive potential and its area of damage covering the entire plant, including such plant parts as the scales of a stem and underground roots, rendered its control difficult. Since A. yasumatsui was only discovered recently in Taiwan, information on its basic biology and ecology has been seriously lacking. This made its control even more difficult. Therefore, we reported here the findings of our study on A. yasumatsui in such areas as the routes of its invasion and dispersion, diagnostic identification, life history and population dynamics, screening of insecticides for its control, survey of its native natural enemies, quarantine treatment with radiation, emergency control, and establishment of a standard operation procedure (SOP) to prevent its further spread into cycad protection areas. The findings of this study may be useful in the develop- ment of an integrated pest management system for A. yasumatsui