State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou, 350002, China.
Sci Rep. 2020 Apr 15;10(1):6447. doi: 10.1038/s41598-020-62021-y.
The use of nectar-providing plants to nourish natural enemies of pest species has become a widely-used approach in conservation biological control to reduce pest damage without the indiscriminate use of insecticides. Choice of plant species is crucial to maximize benefits, but suitable species are yet to be identified for many important crop-pest systems. Here we explored the suitability of three candidate nectar plants for use in brassica vegetables to suppress the globally significant pest, Plutella xylostella L. (Lepidoptera: Plutellidae), using the widely-distributed parasitoid, Cotesia vestalis (Haliday) (Hymenoptera: Braconidae). Volatiles of alyssum (Lobularia maritima (L.) Desv) (Brassicaceae) were attractive to the parasitoid and access to flowering shoots increased adult longevity and realized fecundity of C. vestalis. Moreover, adult diamondback moth derived no benefit from this flower. In contrast, buckwheat (Fagopyrum esculentum Moench) (Polygonaceae), a species widely used in conservation biological control in other systems, increased the longevity and fecundity of both pest and parasitoid, rendering it less suitable. A third plant, heronsbill (Portulaca grandiflora Hook.) (Portulacaceae) denied benefit to the pest and promoted longevity of the parasitoid under no-choice conditions but did not improve fecundity and was repellent to female parasitoids under choice conditions. The contrasting effects of this set of plants illustrate the need to test multiple response variables and effects on both pest and natural enemy when seeking optimal nectar plants for use in a novel conservation biological control system.
利用为传粉者提供花蜜的植物来滋养害虫的天敌，已成为保护生物防治中减少害虫危害的一种广泛应用的方法，无需滥用以色列杀虫剂。植物物种的选择对于最大限度地发挥效益至关重要，但对于许多重要的作物-害虫系统，仍有待确定合适的物种。在这里，我们探讨了利用三种候选花蜜植物来抑制全球重要害虫小菜蛾的适宜性，小菜蛾是十字花科蔬菜的重要害虫，使用广泛分布的寄生蜂 Cotesia vestalis（Haliday）（膜翅目：Braconidae）。金盏花（Lobularia maritima（L.）Desv）（十字花科）的挥发物对寄生蜂具有吸引力，而接触开花枝条则增加了 C. vestalis 的成虫寿命和实现了生殖力。此外，成虫菜粉蝶从这种花中得不到任何好处。相比之下，荞麦（Fagopyrum esculentum Moench）（蓼科），在其他系统中广泛用于保护生物防治的物种，增加了害虫和寄生蜂的寿命和生殖力，使其不太适合。第三种植物，马齿苋（Portulaca grandiflora Hook.）（马齿苋科），在非选择条件下对害虫没有益处，但延长了寄生蜂的寿命，在选择条件下对雌性寄生蜂没有改善生殖力，而且具有驱避性。这一组植物的对比效果表明，在寻求用于新型保护生物防治系统的最佳花蜜植物时，需要测试多个响应变量和对害虫和天敌的影响。
