温室内大花植物对天敌丰度及其控害功能的影响

【目的】大花植物(花粉和花蜜)能否为特殊的寒地温室内各种昆虫的成虫期补充营养,提供食物来源进而影响温室内天敌的控害功能是当前保护地内防控害虫的关键的科学问题之一。【方法】本实验连续两年选择调查了哈尔滨市郊区(寒地,北纬45o)三栋大型玻璃温室的花卉作物栽培引入情况并用粘虫板连续监测了温室内各种节肢动物丰度动态,分析了温室内大花植物栽培比例对各类(种)优势害虫丰度,寄生性天敌及捕食性天敌丰度的影响,探讨了不同天敌类群丰度的关系及害虫多样性与总丰度等关系。【结果】研究表明:较高比例的大花植物栽培整体上能提高害虫的多样性指数,抑制各种害虫种群的暴发,但单一种类的大花植物也会导致较为严重的害虫发生;影响寄生性天敌类群的环境因素与影响捕食性天敌的因素相似,而捕食性天敌(体型较大)对化学农药的喷洒相对更为敏感。【结论】研究结果可为田间生物控害工程的"功能植物"筛选提供信息,为设施农业害虫生物防治提供科学依据。

Impacts of mass-flowering plants on the abundance of natural enemies of arthropod pests in greenhouses in Northern China

Objectives] To determine whether mass-flowering plants in greenhouses in cold regions provide nutrition for adult insects is an important issue related to the effective control of arthropod pests. Methods] The planting structure, species of flying adult insects captured on sticky card traps, influence of planting ratio （mass-flowering plants to other species） on pest abundance and parasitoid abundance were investigated in three independent, large, glass greenhouses in a suburb of Harbin city （Latitude 45°N） in 2010-2011. Predator abundance and the relationship between parasitoids and predators and between pest abundance and diversity were analyzed using linear regression models. Results] The results show that, at least in Northern China, higher ratios of mass-flowering plants can increase the biodiversity of pests and suppress outbreaks of specific pest species in greenhouses. Monocultures of specific mass-flowering plants can, however, also lead to serious pest infestation, and fewer parasitoids and predators. Parasitoids and predators responded to environmental conditions in a similar way, except that predators, which are typically larger than parasitoids, were more sensitive to crop management, especially chemical spraying. Conclusion] This study provides primary information to inform the choice of plants for ＂bio-control engineering＂ of open fields. The methods used can also provide early warning of the invasion of exotic organisms and global change in arthropod biodiversity.