外来广聚萤叶甲在我国的扩散及生活史特征

Dispersal and Bionomics of the Alien Ophraella communa in China Mainland

外来广聚萤叶甲目前已在我国华东的江苏、江西、安徽、浙江等省以及华中的湖北、湖南等省扩散蔓延；在野外其主要寄主是豚草，偶见取食苍耳。广聚萤叶甲在24、27、30℃恒温条件下完成一代分别为29．8、26．0和22．2d；野外完成1代需21～29d。在室外罩笼观察的4个世代中，前3个世代（6—8月）的各虫态历期及其存活率近似，产卵量接近；但9月初开始的第4个世代各虫态历期延长、存活率明显降低，产卵量（108．8粒）低于此前世代的一半。广聚萤叶甲的发育起点温度和有效积温分别为11．5℃和373．5日度；在南京推测广聚萤叶甲1年可发生5代。

The alien leafbeetle OphraeUa communa Lesage has spread to eastern provinces including Jiangsu, Zhejiang, Anhui, Jiangxi, and central southern provinces including Hunan and Hubei. Its main host plants are the invasive ragweed, Ambrosia artemisiifolia Linn., and occasionally Xanthium sibiricum Patrin., a plant Species most close to the ragweed. It took 29.8, 26.07, and 22.2 d to complete a generation at constant temperatures of 24, 27 and 30℃, respectively; but 21 - 29 d in the field at Nanjing city. Among the four generations observed in outdoor cages, the first three from June to August were similar in development duration, survivalship, and fecundity; but for the forth generation, development was much slow, survival rate, obviously low, and fecundity （108.8 eggs per female）, less than half of previous generations. Development threshold temperature was 11.5℃ and effective accumulated temperature for a generation was 373.5 degree-days. It is estimated that five generations can occur per year in Nanjing city.