南亚大眼长蝽和西沙大眼长蝽的捕食功能研究

Predatory function of Geocoris ochropterus and Geocoris xishaensis

【目的】研究海南本土长蝽类天敌昆虫对三亚瓜菜上主要害虫的捕食潜力,为天敌昆虫的田间应用提供基础依据。【方法】在室内不同温度条件下,当南亚大眼长蝽Geocoris ochropterus Fieber和西沙大眼长蝽Geocoris xishaensis与不同害虫共存时,统计2种长蝽分别对普通大蓟马Megalurothrips usitatus Bagrall、豆蚜Aphis craccivora Koch、叶蝉Cicadellidae和露尾甲Haptonchus luteolus的取食偏好性,评估2种天敌对主要猎物普通大蓟马的捕食能力。【结果】与蚜虫、叶蝉和露尾甲相比,2种长蝽对普通大蓟马具有较强的捕食偏好性,且对普通大蓟马成虫捕食偏好性高于蓟马若虫。在不同温度的条件下比较2种长蝽对普通大蓟马的捕食量,结果表明28℃是2种长蝽的最佳捕食温度,南亚大眼长蝽雌虫、雄虫、4-5龄若虫和2-3龄若虫对普通大蓟马的最高日捕食量分别为(49.18±8.71)、(47.23±7.81)、(43.60±10.29)和(30.10±4.65)头/d;西沙大眼长蝽雌虫、雄虫、4-5龄若虫和2-3龄若虫对普通大蓟马的日捕食量分别达到(33.37±3.89)、(32.65±5.12)、(23.87±2.37)和(27.36±3.19)头/d。【结论】南亚大眼长蝽和西沙大眼长蝽成虫和若虫对瓜菜上主要害虫均具有一定的捕食潜力,无论成虫还是若虫对普通大蓟马具有最高的捕食倾向性,且雌成虫对普通大蓟马成虫的捕食能力最强。研究结果为将来2种海南本地长蝽的田间防控应用奠定基础。

[Objectives]To clarify the potential of two predatory stink bugs(Geocoris ochropterus Fieber and G.xishaensis)as biological controls for the main pests of melons and vegetables in Hainan.[Methods]The feeding preferences of the two species of stink bug with respect to common thrips,aphids,leafhoppers and nitidulids were determined,and their ability to control common thrips was evaluated.[Results]Both stink bugs preferred common thrips to the three other pests and adult common thrips to nymphs.The predation rate of both species was highest at 28℃and the maximum daily capture rates of common thrips by adult female,adult male,4th-5th instar nymphs and 2nd-3rd instar nymphs of G.ochropterus were(49.18±8.71),(47.23±7.81),(43.60±10.29)and(30.10±4.65)ind./day,respectively.The maximum daily capture rates of common thrips by adult female,adult male,4th-5th instar nymphs and 2nd-3rd instar nymphs of G.xishaensis were(33.37±3.89),(32.65±5.12),(23.87±2.37)and(27.36±3.19)ind./day,respectively.[Conclusion]Adults and nymphs of G.ochropterus and G.xishaensis are both potentially effective biological controls for the main pests of melons and vegetables.Both species prefer to prey on common thrips,and females of both species were the most effective predators of adult thrips.These findings provide a foundation for the conservation and application of G.ochropterus and G.xishaensis as biological control agents in Hainan.