秋花菜田节肢动物群落结构的研究

目的]研究花菜田节肢动物的群落结构。方法] 以花菜品种雪宝1号F1代为试材，在田间系统调查基础上，分析合肥市西北郊花菜试验田节肢动物群落的物种组成及各种群数量动态，计算群落均匀度和多样性。结果] 调查共记录节肢动物25种，其中害虫12种，天敌13种。害虫主要优势种为菜蚜和斜纹夜蛾；捕食性天敌主要优势种为八斑球腹蛛和草间小黑蛛。害虫和天敌的优势种主要分布于花菜外层叶反面。节肢动物群落多样性在10月上旬前较高，此后较低，在时间过程中呈稳定下降趋势。影响群落多样性的主要因素是群落均匀度。 结论] 调控花菜田节肢动物主要害虫优势种的种群数量，并保护天敌以提高群落的均匀度，是提高群落多样性和稳定性的主要途径。

Study on the Community Structure of Arthropod in Autumn Cauliflower Fields

Objective] The purpose was to research the community structure of arthropod in autumn cauliflower fields.Method] With the cauliflower variety Xuebao 1 F1 as tested material,on the basis of field system investigation,the species composition and each population quantity dynamics of arthropod communities in cauliflower experimental field in northwest suburb of Hefei City were analyzed,and the community evenness and diversity were calculated.Result] In investigation,25 species of arthropods were recorded,among which,pests were 12 kinds and the natural enemies were 13 kinds.The major dominant species of insect pests were Prodenia litura and Lipaphis erysimi.The main dominant species of predator were Theridion octomaculatum and Erigonidium graminicolum.The dominant species of insect pests and natural enemies were distributed mainly on the back of outer leaves of cauliflower.The community diversity of arthropods were higher in the first 10 days of Oct.and lower later,with steady declining trend in time course.The principal factor affecting the diversities was species evenness.Conclusion] The main approach of improving community diversity and stability were: controlling the population quantity of the major pest dominant species of arthropods in cauliflower fields,and protecting natural enemies to enhance community evenness.