Hatt Séverin, Mouchon Pierre, Lopes Thomas, Francis Frédéric
TERRA-AgricultureIsLife, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium.
Functional and Evolutionary Entomology, Department of Agronomy, Biology and Chemistry, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030 Gembloux, Belgium.
Insects. 2017 Sep 13;8(3):99. doi: 10.3390/insects8030099.
Landscape diversification is a key element for the development of sustainable agriculture. This study explores whether the implementation of habitats for pest natural enemies enhances conservation biological control in an adjacent field. In the present study conducted in Gembloux (Belgium) in 2016, the effect of two different habitats (wildflower strips and a forest) and aphid abundance on the density of aphid natural enemies, mummified aphids and parasitism on pea plants was assessed through visual observations. The effect of the habitats on aphids was also evaluated. The habitats but not aphid density significantly affected hoverfly larvae, which were more abundant adjacent to wildflower strips than to the forest. The contrary was observed for ladybeetle adults, which were positively related with aphids but not affected by the adjacent habitats. The abundance of mummies and the parasitism rate were significantly affected by both the habitats and aphid density. They were both significantly enhanced adjacent to wildflower strips compared to the forest, but the total parasitism rate was low (<1%), questioning whether parasitoids could significantly control aphids on the pea crop. As for the aphids, their abundance was not significantly affected by the adjacent habitats. These results are discussed with respect to the potential of these habitats to provide overwintering sites and food resources for natural enemies, and thereby enhance conservation biological control.
景观多样化是可持续农业发展的关键要素。本研究探讨了为害虫天敌营造栖息地是否能增强相邻农田的保护型生物防治效果。在2016年于比利时根特进行的本研究中，通过视觉观察评估了两种不同栖息地（野花带和森林）以及蚜虫数量对豌豆植株上蚜虫天敌密度、僵蚜和寄生率的影响。还评估了这些栖息地对蚜虫的影响。栖息地而非蚜虫密度对食蚜蝇幼虫有显著影响，野花带附近的食蚜蝇幼虫比森林附近的更为丰富。对于瓢虫成虫则观察到相反的情况，它们与蚜虫呈正相关，但不受相邻栖息地的影响。僵蚜数量和寄生率均受到栖息地和蚜虫密度的显著影响。与森林相比，野花带附近的僵蚜数量和寄生率均显著提高，但总寄生率较低（<1%），这使人质疑寄生蜂是否能显著控制豌豆作物上的蚜虫。至于蚜虫，其数量不受相邻栖息地的显著影响。针对这些栖息地为天敌提供越冬场所和食物资源的潜力，进而增强保护型生物防治效果，对这些结果进行了讨论。
