基徵草蛉(脈翅目：草蛉科) 對柑橘潛葉蛾 (鱗翅目：潛葉蛾科) 寄生蜂之影響

Abstract

於柑橘園中調查發現橘潛蛾(柑橘潛葉蛾，Phyllocnistis citrella )的寄生性天敵有4科9種，其中6種屬於釉小蜂科。橘潛蛾幼蟲最主要的寄生蜂是白腹嚙小蜂(Citrostichus phyllocnistoides)，其寄生率大多在40-60%之間，其次是串繭跳小蜂(Ageniaspis citricola)，寄生率多在40%以下。串繭跳小蜂同時也是橘潛蛾蛹期的主要寄生性天敵，在9月或10月份寄生率最高，幾達80%。每年6月之前田間橘潛蛾寄生蜂之總寄生率較低，以後才漸次上升。於柑橘園中釋放基徵草蛉(Mallada basalis)，不論是草蛉釋放區或對照區，橘潛蛾的被寄生率變動趨勢一致。實驗室內的觀察結果顯示，各齡期的基徵草蛉幼蟲都會捕食橘潛蛾幼蟲，而此蛾幼蟲被寄生與否並不影響草蛉的捕食。但是只有三齡草蛉幼蟲有能力捕食橘潛蛾的蛹。田間及實驗室內捕食結果說明釋放基徵草蛉會減少橘潛蛾及寄生蜂的密度，但是對橘潛蛾被寄生率沒有負面影響。 Nine species of parasitoids were found with the citrus leafminer, Phyllocnistis citrella, in citrus orchards in central Taiwan. These hymenopterous wasps belong to 4 families, with 6 species from the family Eulophidae. Citrostichus phyllocnistoides, one of the eulophid wasps, was the major larval parasitoid, with 40% to 60% of leafminer larvae parasitized by this wasp. Second to it was the encyrtid wasp, Ageniaspis citricola. Most leafminer larvae were parasitized by these 2 species. A citricola was the most frequently found pupal parasite, with as much as 80% of the pupae being attacked by this species during September and Octobe. Field surveys showed that parasitism of leafminers was low during the citrus shooting stage from March to June. The Ist to 3rd instar chrysopid, Mallada basalis, could prey on larvae of leafminers. The chrysopid fed on the host irrespective of itself being parasitized or not. Only lacewings of the 3rd instar could prey on pupated leafminers. The results from field and laboratory observations reveal that the release of chrysopids can decrease the numbers of both citrus leafminers and parasitoids. However, the overall percentages of leafminers parasitized were not affected.