斯氏钝绥螨在北京地区冬季室外存活情况及定殖性评估

Survival and Establishment Potential of Amblyseius swirskii in the Winter in Beijing, China

斯氏钝绥螨Amblyseius swirskii(Athias-Henriot)是一种自然分布在地中海东部和东南部地区的多食性捕食螨,其能有效控制烟粉虱。鉴于目前我国没有良好的可用于商业化防治烟粉虱的本土捕食螨品种,考虑释放应用斯氏钝绥螨,用于我国温室烟粉虱的防治。外来生防因子在释放应用前需进行风险评估,而生防因子定殖能力的评估是风险评估的重要组成部分。本文根据斯氏钝绥螨的发育起点温度和有效积温,结合北京地区气象数据,推算斯氏钝绥螨在北京地区可否获得足够的有效积温完成生长发育,在此基础上进行其在北京地区冬季的室外存活试验,再结合该螨已知的热生物学特性和耐寒性,推定斯氏钝绥螨在我国北京地区定殖的可能性。试验结果表明,斯氏钝绥螨在北京地区一年可发生20代,但从11月到来年3月间的有效积温仅为9.6日度,不足以使斯氏钝绥螨完成一个世代;斯氏钝绥螨在冬季室外放置35 d时,死亡率达到100%;从2012年11月6日到2013年1月25日间每10 d在室外放置1批,共9批的斯氏钝绥螨,在2013年4月6日取回时,死亡率全部为100%。结合试验数据和已知斯氏钝绥螨的生物学特性,得知斯氏钝绥螨在北京地区冬季定殖的可能性极低。

Amblyseius swirskii (Athias-Henriot), native to the eastern and southeastern part of the Mediterranean region, is a polyphagous predatory mite used for the control of whiteflies. Due to the lack of commercialized predatory mites for controlling whiteflies in China, we are intending to introduce the predatory mite to control greenhouse whiteflies. According to regulations, environmental risk assessment is fundamentally necessary before the release of exotic natural enemies, among which establishment potential evaluation is a priority. The study estimated potential annual voltinism using degree-day model with temperature data from Beijing Meteorological Station, and assessed winter field survival of the predator. The results showed A. swirskii could complete a total of 20 generations per year in Beijing, but it was not able to complete life cycle from the beginning of November to the end of March. The predators all died when they were placed outdoor for 35 days. These results show that A. swirskii is unable to establish population in the winter in Beijing, China.