松突圆蚧种群动态及与气象因子的关系

Dynamic of Hemiberlesia pitysophila population and the relationships with climate factors

2003年松突圆蚧上半年的虫口数量高于下半年,3月中旬到6月下旬的虫口数量高,7月上旬到10月上旬的虫口数量低,10月下旬到12月下旬的虫口数量较高.低龄若虫(1龄若虫和分化前2龄若虫)的虫口变动趋势与种群一致,是引起种群波动的重要原因.种群及其各虫态的死亡率动态基本上与虫口数量呈相反趋势,7-10月低龄若虫死亡率高是引起该阶段种群及低龄若虫数量低的主要原因.气象因子中气温对种群有着极重要的影响,高温不利于种群的扩张,对低龄若虫的影响高于高龄虫态.

By means of a year cycle systematic survey on sampling place of pine forest attacked by Hemiberlesia pitysophila Takagi in Fuqing, Fujian Province in 2003, the results showed that the pest population number of H. pitysophila kept a much high level during the middle ten days of March to the last ten days of June, and kept a high level during the last ten days of October to the last ten days of December, but kept a low level during the first ten days of July to the first ten days of October. The number dynamic of the young nymphae of the pest was similar with the population very much, which significantly led to the fluctuate of the population. The dynamic of population mortality in a year appeared opposite trend on the whole. The low number of population during July to October was led to by high mortality of the young nymphae in this stage. Moreover, air temperature effected the population significantly. Hightemperature didn＇t benefit to expand of the population. The effects on young nymphae were more than those on the other development stage of the pest.