白背飞虱的迁飞生物学:江苏苏州个例分析

对苏州市吴中区1984—2002年灯诱数据的分析表明,白背飞虱Sogatella furcifera(Horváth)的灯下始见期一般在6月上旬,而主迁峰日则一般出现在7月上旬。1996年后,始见期有提前的趋势。对18年灯诱虫量的时间序列分析表明,田间迁入代虫量与6月份的灯诱虫量相关,田间第1代虫量与迁入代虫量相关,第2代则只与田间第1代和8月份的诱虫量相关。对1986—2002年吴中区白背飞虱田间虫量的分析表明,白背飞虱在田间一般要完成2个世代,20世纪90年代中期之后会出现第3代,表现出低迁入率(平均百穴21头)、高增殖倍数(G1/G0在30～200倍左右)和高峰值密度(16年平均百穴3200头)的种群特征。此间白背飞虱长翅型成虫的比率不高,迁入后便像褐飞虱Nilaparvata lugens(Stl)那样形成了滞留本地的增殖代(7月20日到8月10日)和以本地滞留为害与部分迁出个体混合而成的主害代(8月15日到9月5日),直到8月下旬和9月上中旬,其长翅型比率才会有大幅回升开始回迁,呈现出翅型长-短-长的变化模式。

Migratory biology of the white backed planthopper:Case studies in Suzhou,Jiangsu Province

The immigration behaviour of the white-backed planthopper Sogatella furcifera（Horváth）（WBPH） was analyzed based on light-trap catches in Wuzhong,Suzhou from 1984 to 2002.The first captures were in early June but appear to have occurred progressively earlier since 1996.The peak of immigration also occurred in early July.The number of immigrants in paddy fields was correlated with light trap catches in June and determined the local population size of the first and second generation.Based on field survey data from 1986 to 2002,we found that the WBPH emigration behaviour has also changed gradually since the mid 1990＇s.Generally,the offspring generation of immigrants would mostly emigrate when the macropterous adults emerged,but like brown planthopper Nilaparvata lugens（Stl）（BPH）,a proliferation generation（20 July-10 Aug.） and a damage generation（15 Aug.-5 Sep.） have subsequently been observed.The ratio of macropterous individuals in the population was not high in these generations until the appearance of the emigrant generation in September.The population characteristics can be characterised as low immigration（mean 21 hoppers per 100 hills）,high proliferation（G1/G0,30-200 times） and high peak density（16 year mean of 3 200 hoppers per 100 hills）.The latter has a new wing-form pattern in successive generations of ＇macropterous-brachypterous-macropterous＇.