温度对芙新姬小蜂孤雌产雌品系成虫控制斑潜蝇的潜力的影响

【目的】芙新姬小蜂Neochrysocharis formosa是潜叶蝇类害虫的优势寄生蜂。该寄生蜂具有两性生殖和孤雌产雌生殖两种繁殖模式，其孤雌产雌品系可在低密度下快速建立种群，无需饲养雄蜂，具有种群繁育成本低，生防应用潜力突出等优点。本研究旨在明确环境温度对芙新姬小蜂孤雌产雌品系控害潜力的影响，为该蜂的低成本规模化繁育、田间释放等应用实践提供参考。【方法】在室内以美洲斑潜 蝇Liriomyza sativae 2龄末至3龄初幼虫为寄主，统计4个温度(22, 26, 30和34℃)下芙新姬小蜂孤雌产雌品系雌成虫的取食致死寄主数、寄生致死寄主数、叮蛰致死寄主数、总致死寄主数、日均致死寄主数和成蜂寿命等生活史和控害参数。【结果】随温度升高，芙新姬小蜂孤雌产雌品系雌成虫对美洲斑潜蝇幼虫取食致死寄主数、寄生致死寄主数、叮蛰致死寄主数、总致死寄主数和日均总致死寄主数呈现先增加后降低的趋势，其中取食致死寄主数、寄生致死寄主数和叮蛰致死寄主数在30℃下最高，分别为236.1, 69.2和49.7头；在34℃下最低，分别为115.2, 19.8和21.6头。总致死寄主数在26℃(282.4头)和30℃(355.0头)下显著高于22℃(194.5头)和34℃下(156.5头)；日均总致死寄主数在30℃下最高(25.5头)。此外，随着环境温度升高，芙新姬小蜂孤雌产雌品系雌成虫的寿命逐渐缩短，在22℃下最长(16.9 d)，在34℃下最短(7.2 d)。【结论】尽管高温缩短了芙新姬小蜂孤雌产雌品系成虫的寿命，但其在30℃下控害能力较强，说明芙新姬小蜂孤雌产雌品系成虫可在30℃高温条件下对耐高温的斑潜蝇如美洲斑潜蝇发挥其控害潜力。

Effects of temperature on the biocontrol potential of thelytokous adults ofNeochrysocharisformosa(Hymenoptera: Eulophidae) against agromyzid leafminers

【Aim】 Neochrysocharis formosa is a dominant parasitoid against agromyzidleafminers. Both arrhenotoky and thelytoky exist in N. formosa. Thelytokous individuals canquickly establish populations at a low density without the need of raising drones, and the thelytokous strain show more important potential in terms of breeding cost and biologicalcontrol application. This study aims to analyze the effects of ambient temperature on thebiocontrol potential of thelytokous N. formosa so as to provide reference for its large-scale breeding and field release. 【Methods】 The late 2nd to the early 3rd instarlarvae of Liriomyza sativae were used as hosts. The life history traits and biocontrolparameters including the numbers of host-feeding events, parasitism events, andhost-stinging events, total number of host-killing events, daily number of host-killingevents and longevity of the thelytokous female adults of N. formosa at four temperatureconditions (22, 26, 30 and 34℃) were assessed in the laboratory. 【Results】 The numbers of host-feeding events, parasitism events and host-stinging events, total number of host-killing events, and daily total number of host-killing events of thelytokous femaleadults of N. formosa increased generally and then decreased with the temperatureincreasing. The numbers of host-feeding events, parasitism events, and host-stingingevents reached the peak at 30℃, which were 236.1, 69.2, and 49.7, respectively, andwere the lowest at 34℃, which were 115.2, 19.8 and 21.6, respectively. The total numbersof host-killing events at 26℃ (282.4) and 30℃ (355.0) were significantly higher thanthose at 22℃ (194.5) and 34℃ (156.5), and the daily total number of host-killing eventsreached the peak at 30℃ (25.5). In addition, the longevity of thelytokous female adults of N. formosa was the longest at 22℃ and the lowest at 34℃, which were 16.9 and 7.2 d,respectively, indicating that the life span of this parasitoid gradually decreased with theincrease of temperature. 【Conclusion】 Although high temperatures shorten the longevity ofthe thelytokous adults of N. formosa, they show the pronounced ability to kill the host at30℃, suggesting that the thelytokous adults of N. formosa can exert their biocontrolpotential at 30℃ against such agromyzid leafminers with high heat tolerance as L. sativae.