螺旋粉蝨之田間發生與寄主影響

Abstract

螺旋粉蝨之田間消長經三年（79～82）調查結果，顯示其每一年族群變動型式相當一致，其密度均由10月中旬開始增加，11月中旬達高峰，12月下旬開始下降。其在25℃於聖誕紅、美人蕉、番石榴及木瓜植株上之發育期（卵～蛹）分別為26.1、25.0、29.4及26.1日，成蟲前期死亡率分別為26.9%、24.5%、33.3%及27.8%，雌成蟲平均產卵數為65.2、35.8、51.3及58.0粒。螺旋粉蝨於混合寄主植物上之族群略低於單一寄主值物上。寄主植物經修剪或增施氮肥後會促使產生新芽及葉，而有利於本蟲之發生。 The spiralling whitefly can be found all year round in southern Taiwan. The population built up rapidly in October, with a peak in November, and declined gradually after December. The developmental time (from oviposition to eclosion) of spiralling whitefly at 25℃ on poinsettia, canna, guava and papaya were 26.1, 25.0, 29.4 and 26.1 days; immature mortality were 26.9%, 24.5%, 33.3% and 27.8%; fecundity were 65.2, 35.8, 51.3 and 58.0 eggs per female, respectively. The population density of spiralling whitefly was higher on mono crop field then field with several crops. High nitrogen fertilizer or pruning caused plant to produce new shoots and young leaves which attracted more adults to lay eggs and to feed on them.