低温磷化氢熏蒸对木瓜实蝇的毒力研究

Research on the toxicity of low temperature phosphine fumigation against papaya fruit fly

木瓜实蝇(Bactrocera papayae Drew and Hancock)严重危害多种热带和亚热带经济水果和蔬菜,是许多国家关注的重要检疫性有害生物之一。本文系统研究了磷化氢在低温条件下对木瓜实蝇的毒力。耐受性分析结果表明,木瓜实蝇各虫态对磷化氢的耐受力有很大差别,其耐受能力强弱依次为12 h卵>3龄幼虫>18 h卵和2龄幼虫>24 h卵>6 h卵和1龄幼虫;室内毒力实验结果表明,使用浓度为0.421、0.919、1.372、1.829、2.439和5.335mg/L的磷化氢在5℃下熏蒸木瓜实蝇12 h卵不同时间,其LT99分别为8.046、7.154、6.797、5.78、5.218和3.495 d。以此为依据,推导出死亡率为99%时,熏蒸时间与浓度的关系可表示为C0.558t=K,表明熏蒸时间是影响低温磷化氢熏蒸木瓜实蝇卵的主要因素。本文首次用低温磷化氢对木瓜实蝇卵的熏蒸毒力进行了系统研究,确认了磷化氢低温熏蒸技术在果蔬携带木瓜实蝇的检疫处理中极具应用前景。

The papaya fruit fly(Bactrocera papayae Drew and Hancock) is one of the most serious pests of many sub-tropical and tropical fruits and vegetables, thus considered an important quarantine pest in many countries. The fumigating toxicity of phosphine against papaya fruit fly at low temperature was systematically studied in this article. Tolerance analysis results showed that the tolerance of different stages of papaya fruit fly to phosphine fumigation differed greatly and the tolerance from strong to weak was followed by 12 h eggs, 3rdinstar larvae, 18 h eggs and 2nd instar larvae, 24 h eggs, 6h eggs and 1stinstar larvae. The laboratory toxicity test results showed that the LT 99 values were 8.046, 7.154,6.797, 5.78, 5.218 and 3.495 d while the phosphine concentrations were 0.421, 0.919, 1.372, 1.829, 2.439 and 5.335 mg/L respectively at 5℃. According to these results, the expression of C0.558t=K was obtained, which indicated that exposure time is more important in phosphine fumigation. Our results gave detail data of the toxicity of phosphine against fruit flies at low temperature, and suggested that disinfection of papaya fruit fly with low temperature phosphine fumigation could be achievable.