外来入侵生物烟粉虱的生物学特性及种群数量消长规律研究

根据2005～2010年应用塑料黄板涂抹机油系统诱集烟粉虱成虫以及烟粉虱的饲养观察结果表明,烟粉虱在临海地区年可发生11代;其越冬的临界温度为旬平均气温8.5℃。随着寄主植物的生长,成虫逐渐向上部叶片转移,并形成植株自上而下为成虫(初产卵)、若虫和蛹壳(伪蛹)的虫态垂直分布状态。其全年种群数量消长主要呈双峰型曲线变化,其中夏峰期一般在5月中旬至9月上旬;秋峰期一般在10月中旬至11月下旬。影响种群数量消长的主要因素有种群基数、气候条件、耕作制度和洪涝淹没等。其中关键在于气温条件,即烟粉虱虫口密度(M)随气温(T℃)的变化而变化,其线性关系模型为M=0.607T-4.064 5,n=36;r=0.682 6**;其曲线关系模型为M=0.007 1T2+0.351 3T-2.218 8,n=36;r=0.684 6**。当旬平均气温在8～10℃时种群处存活临界状态;当旬平均气温在10～20℃时种群数量处低密度状态,并呈低位运行;当旬平均气温处20℃以上种群数量增速较快,并随气温升高而升高;当旬平均气温处30℃以上时种群数量有所回落,并出现相对低谷期。随后种群数量又回升成峰,并对秋季蔬菜产生较重为害。

Study on biology characteristics and population dynamics of invasive Bemisia tabaci (Gennadius )

Based on observation of Bemisia tabaci(Gennadius) breeding and trapping by plastic yellow board with oil from 2005 to 2010,the results indicated that there were 11 generation of B.tabaci in Linhai region,and the critical temperature for its over-wintering was 8.5 ℃.The adult moved to upper leaves with host growth,and develop a vertical distribution model as adult,nymphae,and puparium from top to bottem.The population dynamics showed mainly as double peak curve in a whole year with the summer peak during mid May to early September and autumn peak during mid October to late November.The major impact factors on population dynamics were population base,climate,cropping system and flood and waterlogging.And the critical factor was air temperature(T ℃),which had effect on population density(M) of B.tabaci as linearity model and curve model followed: M=0.607T-4.064 5,n=36;r=0.682 6,M = 0.007 1T 2 + 0.351 3T-2.218 8,n=36;r=0.684 6.The critical temperature for population survival was on ten days average temperature of 8～10 ℃,low density of population was on ten days average temperature of 10～20 ℃,population increased fast as the ten days average temperature above 20 ℃ and increased with temperature increase,and population setback as the ten days average temperature beyond 30 ℃ and showed low point.After that,population of B.tabaci reached the peak again and brought seriously damage to autumn vegetables.