Department of Entomology, Texas A&M AgriLife Research and Extension Center, Overton, TX, USA.
Texas A&M AgriLife Research, Texas A&M AgriLife Research and Extension Center, Overton, TX, USA.
Environ Entomol. 2021 Jun 18;50(3):561-570. doi: 10.1093/ee/nvab007.
Whether increased natural enemy density or adding a second natural enemy species will provide superior pest suppression in greenhouse augmentative biological control is unknown for many commercially available natural enemy species. In this study, we use sweetpotato whiteflies, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), on poinsettias, Euphorbia pulcherrima Willd. ex Klotzsch (Malpighiales: Euphorbiaceae), to determine whether adding Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) to Eretmocerus eremicus Rose and Zolnerowich (Hymenoptera: Aphelinidae) is better for B. tabaci suppression compared with either natural enemy alone, both with and without challenges with whitefly immigration or delayed natural enemy releases. The number of whiteflies on caged poinsettias treated with different natural enemy release rates (single or double rate), natural enemy species (one or two species), natural enemy delayed release (weeks 4 and 8), and whitefly immigration treatments (introduced at week 4 or week 8) was censused biweekly for 16 wk. Both species used in combination provided similar or better suppression of whiteflies compared with either natural enemy alone. Both species combined also provided superior suppression of whiteflies when challenged with whitefly immigration or delays in natural enemy releases compared with E. eremicus alone. Whitefly immigration or delays in E. eremicus releases did not increase whitefly populations, suggesting that suppression of whiteflies by E. eremicus alone is relatively robust. This study found no evidence for negative interactions between E. eremicus and A. swirskii for suppressing B. tabaci.
对于许多商业上可用的天敌物种，增加自然天敌的密度或添加第二种天敌物种是否会在温室增强生物防治中提供更好的害虫抑制效果尚不清楚。在这项研究中，我们使用甘薯粉虱（Bemisia tabaci）（半翅目：粉虱科）在一品红（Euphorbia pulcherrima）（大戟科）上，以确定添加斯氏钝绥螨（Amblyseius swirskii）（叶螨科）到玫红新绥螨（Eretmocerus eremicus）（膜翅目：缨小蜂科）是否比单独使用任何一种天敌对 B. tabaci 的抑制效果更好，同时还考虑了粉虱入侵或延迟天敌释放的挑战。用不同的天敌释放率（单倍或双倍）、天敌物种（一种或两种）、天敌延迟释放（第 4 周和第 8 周）和粉虱入侵处理（第 4 周或第 8 周引入）处理的笼养一品红上的粉虱数量每两周进行一次统计，共进行 16 周。与单独使用任何一种天敌相比，两种天敌联合使用对粉虱的抑制作用相似或更好。当受到粉虱入侵或天敌释放延迟的挑战时，两种天敌联合使用也比单独使用玫红新绥螨提供了更好的粉虱抑制效果。粉虱入侵或玫红新绥螨释放延迟并没有增加粉虱的数量，这表明玫红新绥螨单独对粉虱的抑制作用相对较强。本研究没有发现玫红新绥螨和斯氏钝绥螨在抑制 B. tabaci 时存在负相互作用的证据。
