Abstract Perina nuda (Fabricius) distributes widely around Taiwan island specially in spring and autumn seasons and is a major pest of banyan, Ficus spp. The larvae are reared with leaves of banyan at 20±1℃, 80-85% RH and 12 hr photoperiod. The developmental period lasts for 50.29±2.17 days. Six larval stadia are found and their developmental time for each larval instar are 5.17±0.37, 4.54±0.50, 4.72±0.64，5.28±0.55，5.22±0.78 and 7.83±0.72 days respectively. The full-grown larva forms a pupal case and pupates on the upper side of leaf. The sexual determination of pupae can be distinguished by their sizes and sites of genital openings. The daily emergence peak appears at 7-9 AM. The peak of copulation time appears at noon from 11：00 AM to 1：30 PM. Female moth lays 272.7±73.4 eggs in its lifetime of 7.88±3.44 days. Male moth has a somewhat shorter life span, 7.43±2.79 days. The epizootic disease of the P. nuda, i. e., nucleopolyhedrosis, occurs periodically at early summer of every year in Taiwan. In vivo propagation of PnMNPV in pupae is also studied in this study. The moribund male pupae and female pupae by injection with PnMNPV suspension (10μl) could produce 4.72×108 and 9.07×108 PIBs per gram respectively. It is suggested that the PIB harvest from moribund pupae is more convenient than from larvae due to avoiding food contamination and losing most of PIB from the fragile body.
摘要 榕樹透翅毒蛾 Perina nuda (Fabricius) 在台灣出現於春季到秋季間，為榕樹的主要害蟲。幼蟲以新鮮的榕樹葉飼育於20±1℃，相對濕度80-85%，12小時光照下完成一世代約需50.29±2.17天。幼蟲共有六齡，發育時間分別為5.17±0.37、4.54±0.50、4.72±0.64、5.28±0.55、5.22±0.78、7.83±0.72天。末齡幼蟲吐絲形成稀疏之蛹室於葉面再化蛹。蛹之性別決定可由體型大小及生殖孔的位置區辨。羽化高峰出現於上午7-9點，交尾高峰出現於中午 (上午11：00至下午1.30)。每隻雌蟲可產卵272.7±73.4個。雌蟲壽命平均為7.88±3.44天，雄蟲略短為7.43±2.79天。春末夏初幼蟲易發生周期性核多角體病的流行，本研究亦利用蛹期生產核多角體病毒。每克雄蟲可產生4.72×108 PIBs，雌蟲可產生9.07×108 PIBs。結果顯示以蛹期回收核多角體較自幼蟲回收者具有不會被食物污染及易於流失之優點。
| Key words: Perina nuda, life history, PnMNPV. | | 關鍵詞: 榕樹透翅毒蛾、生活史、核多角體病毒。 |
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