西藏拉萨地区西花蓟马种群生命表及发生动态研究

Life table and population dynamics of Frankliniella occidentalis in Lhasa, Tibet

【目的】明确拉萨地区西花蓟马Frankliniellaoccidentalis的生物学特性和田间动态规律。【方法】建立了该种群的两性生命表,采用黄板诱集成虫的方法调查了日光温室番茄上西花蓟马的周年发生动态。【结果】该种群西花蓟马成虫前期总发育历期为12.54 d,2龄若虫发育历期为5.62 d,占成虫前期发育历期的44.8%,卵能存活到成虫阶段的概率为0.598。雌虫的平均寿命为27.76 d,雄虫为20.2 d。该种群的内禀增长率(r)和净增殖率(R0)分别为0.153/d和22.817。在拉萨日光温室番茄上西花蓟马能够周年发生,种群增长呈"单峰"型,6月中旬至8月上旬为发生盛期。【结论】拉萨地区西花蓟马的2龄若虫期明显较长,日光温室中西花蓟马的最佳防治适期在4月初。

[Objectives] To determine the biological characteristics and population dynamics of Frankliniella occidentalis in Lhasa.[Methods] Life tables for each sex were compiled, and the population dynamics of F. occidentalis on tomato plants in a solar greenhouse was investigated using yellow sticky-card traps.[Results] The pre-adult developmental time of F.occidentalis was 12.54 d, and that of the second instar nymph was 5.62 d, accounting for 44.8% of the pre-adult period. The probability of eggs surviving to adulthood was 0.598. The average longevity of females was 15.18 d, whereas that of males was 9.64 d. The intrinsic rate of increase(r) and net reproductive rate(R0) were 0.153/d and 22.817, respectively. Adult F.occidentalis were trapped all year round in the solar greenhouse. The population growth curve was of the "single peak" type,with the peak corresponding to the peak of adult emergence from mid-June to early August.[Conclusion] The developmental period of second instar nymphs of F. occidentalis in Lhasa city was obviously longer than that of the first instar,and the optimum control period in greenhouses is in early April.