多蜜源植物生草组合对苹果害虫和天敌的影响

在苹果园自然生草基础上,适当种植紫花苜蓿、长柔毛野豌豆、孔雀草、万寿菊等显花(蜜源)植物,调查其对果园害虫和天敌群落动态造成的影响。结果表明:供试苹果园害虫主要有绣线菊蚜和釐纹细蛾,绣线菊蚜为优势种,组合生草区害虫数量明显少于自然生草区;有蜜源植物的组合生草区害虫相对多度减小,总量减少93.67%。苹果园主要天敌有龟纹瓢虫、异色瓢虫、中华通草蛉、食蚜蝇、小花蝽等,组合生草区树冝上天敌总量增加43.96%,生草中天敌增加16.89%,益害比明显高于1∶25。

Effects of grass pattern with muti-nectariferous plants on pests and natural enemies in apple orchard

We planted some flowering(nectariferous) plants such as Medicago sativa, Vicia villosa, Tagetes patula and Tagetes erectas appropriately on the basis of natural grass pattern in apple orchard and explored the impact on the dynamics of pests and natural enemies. The results showed that Aphis citricola and Lithocolletis ringoniella were main pests in apple orchard and A. citricola was the dominant species. The number of pests in combined grassy area are obviously less than the natural grassy area. The relative abundance of pests in combined grassy area which had nectariferous plants was decreased, and the total number of pests was decreased by 93.67%. The main natural enemies in apple orchard were Propylaea japonica, Harmonia axyridis, Chrysoperla sinica, Syrphidae, Orius similis and so on. The number of natural enemies on trees in combined grassy area were increased by 43.96%, and the number of natural enemies on grass were increased by 16.89%, and the predator prey ratio was obviously higher than 1∶25.