生态因素对橄榄星室木虱种群消长的影响

INFLUENCE OF ECOLOGICAL FACTORS ON THE POPULATION FLUCTUATION OF Pseudo phaco pteron Canarium YANG & LI(HOMOPTERA:CHERMIDAE)

橄榄星室木虱是福建橄榄最重要的害虫.此虫在橄榄幼树上的种群数量比在老树上的大得多,且两类树上的种群消长动态也存在较大的差异.在幼树上,全年出现5个虫口高峰,5月中旬至7月初或7月初至8月上旬为全年最高峰;而在老树上全年只有3个高峰,全年最高峰在3月上旬至5月初.田间橄榄星室木虱种群数量的消长与寄主抽梢期有极密切极敏感的伴随关系,橄榄枝梢生长前后期营养状况的变化对橄榄星室木虱种群消长影响最大,每一个抽梢期都带来一个高的种群增长率和虫口高峰.混种、高湿、极度低温、强降雨以及秋季天敌数量的上升对橄榄星室木虱都有较大的抑制作用。

Pseudo phacopteron canarium Yang & Li is a most important insect pest of Chinese ol- ive.The density of the insect population in the young trees of Chinese olive is greater than that in the old-stage trees,the population dynamics in these two kinds of trees also have considerable difference.In the young trees,there are five population peaks in a year,the highest peak appears between the middle ten days of May and early July in Minqing district,and appears between early July and the first ten clays of August in Minhou district. But there are only three peaks in the old-stage trees in a year,the highest peak appears be- tween the first ten days of March and early May.The insect population fluctuation has a close accompanying relation with the sprouting stage of the host,the variation of the nutri- tion condiction in the earlier and later stages of the twig growth has the greatest effect on the population fluctuation of the insect. Every sprouting stage brings a high rate of population increase and a peak.General mixed farming,high humidity,extreme low-temperature,strong rainfall and the rising of the amount of natural enemies have relatively great inhibiting effect on Pseudo phaco pteron canarium.