原创《苹果园地面植被优化组合对害虫和天敌群落影响》：此文是一篇优化组合论文范文,为你的毕业论文写作提供有价值的参考。
摘 要：
为系统评价苹果园地面不同植物的优化组合对地面植被和树冠上害虫和天敌群落的影响,明确不同植被组合对树冠害虫和天敌群落的影响规律,三种植物（紫花苜蓿、夏至草和泥胡菜）按照不同比例在果园地面种植,采用扫网法和目测法分别调查地面植被和苹果树冠上害虫和天敌的种类及其数量,通过数据分析比较不同植被组合对节肢动物群落结构的影响.结果表明：植被多样化对地面植被上天敌种群特别是小花蝽的种群密度具有显著的促进作用,而天敌数量的增加对害虫种群具有极佳的抑制效果.地面植被的优化组合对树冠节肢动物群落的影响也不一致：单纯苜蓿区（处理1）、25%夏至草区（处理4）和35%夏至草区（处理5）天敌密度分别是清耕园的1.08、1.29和2.48倍,同时害虫数量仅为清耕园的71.95%、62.68%和74.41%,且能够促进早春天敌的种群建立和增殖,物种丰富度和天敌多样性也显著增加.总之,地面植被的不同组合能够调节苹果树冠上害虫和天敌的种群结构,形成有利于天敌不利于害虫的果园生境,对早春天敌的种群建立和生物控害具有显著的促进作用.
关键词：苹果园；紫花苜蓿；夏至草；泥胡菜；自然天敌；生物控害
中图分类号：S436.611.2文献标识号：A文章编号：1001-4942（2016）08-0102-07
AbstractThe goal of the present study was to assess the impacts of combinations of cover plants on the pests and natural enemies in apple orchards and confirm the optimal combination. The cover plant species, including Medicago sativa, Lagopsis supine and Hemistepta lyrata, were planted by different percentage under apple tree canopy. The arthropods on cover plants and in apple tree canopy were sampled by net sweeping and visual observations, respectively. The arthropod community structure was also compared by various methods among different treatments. The results showed that the diversty of cover plants had positive impacts on the abundance of natural enemies, especially Orius sp., and the increased populations of natural enemies could effectively suppress the pest abundance on cover plants. The responses of arthropods in apple tree canopy to different cover plant combinations were also different. The abundance of natural enemies in 100% M. sativa, 25% L. supine and 35% L. supine regions were 1.08, 1.29 and 2.48 times of that in clean-cultivated orchards, respectively, and the density of pests were 71.95%, 62.68% and 74.41% of that in clean-cultivated orchards, respectively； further more, these combinations of cover plants promoted the establishment and enlargement of natural enemy populations in early spring, and the species richness and diversity of natural enemies also increased significantly. These results clearly indicated that different comopositions of ground cover plants could regulate the structure of arthropod community and natural enemy populations in apple tree canopy, create advantageous conditions for natural enemies but not for pests. Therefore, cover plants play important roles in promoting the eatablishment and enlargement of natural enemy population in early spring and enhancing biocontrol of pests.
KeywordsApple orchard； Medicago sativa； Lagopsis supine；Hemistepta lyrata；Natural enemy； Biological control
优化组合论文参考资料：
结论：苹果园地面植被优化组合对害虫和天敌群落影响为关于优化组合方面的论文题目、论文提纲、优化组合创新论文开题报告、文献综述、参考文献的相关大学硕士和本科毕业论文。
