梨 樹 主 要 害 蟲 之 發 生 生 態 與 防 治

376 梨 栽 培 管 理 技 術 研 討 會 專 輯Occurrence, Ecology of Major Pestsof Pear and Their ControlWen-Jer WangTaichung District Agricultural Research and Extension StationAbstractA large number of pests have been recorded for pear, one of the threemost important fruit trees in Taiwan. This report describes only thosecommonly seen in surveys made over the years in Taichung DistrictAgricultural Improvement Station. A total of 24 insects and 4 other pests havebeen found in pear orchards in central Taiwan, with their occurrence varyingwith elevations of cultivation. Pests that occur in both low and highelevations include Aphis gossypii, Myzus persicae, Aphanostigma piri, Iceryapurchasi, Planococcus minor, Pseudaulacaspis pentagona, Crisicoccuschipponensis, Cacopsylla chinensis, Cacopsylla qianli, Nezara viridula,Zeuzera coffeae, Frankiniella intonsa, Anoplophora maculata, Bactroceradorsalis, Tetranychus uritcae and Bradybaena similaris. Aphis pomi,Quadraspidiotus perniciosus, Orgyia postica and Porthesia taiwana areprimarily found in pear orchards of low elevation and rarely seen in orchardsof high elevation. On the other hand, Acalodes sp., Apoderus sp., Phyllobiussp., Psacothea hiraris, Batocera lineolata, Aguriahana triangularis andPanonychus ulmi occur only in pear orchards of high elevation, but never inlow elevation. Therefore, formulating proper measures, based on the kinds ofpests and their population fluctuations in pear orchards for each region, isessential for the economical, safe and effective control strategy.Key word:pear, pest, ecology and control