温度对草地贪夜蛾飞行能力的影响

Effect of temperature on flight capacity of the fall armyworm, Spodoptera frugiperda

为明确温度对草地贪夜蛾飞行能力的影响,采用昆虫飞行磨技术测定了不同温度处理的草地贪夜蛾的飞行能力。结果表明:草地贪夜蛾整个世代在5种不同温度(20、24、28、32和36℃)下饲养羽化的2日龄成虫吊飞10 h的飞行能力差异显著(P<0.05)。其中24、28和32℃条件下饲养的个体飞行能力较强,32℃时达到最大值,其平均飞行距离最远,为(29.48±2.73)km,平均飞行时间最长,为(7.21±0.45)h,平均飞行速度也最快,为(4.02±0.19)km/h。飞行距离超过30 km的个体占40%,飞行时间超过8 h的占45%。低温(20℃)或高温(36℃)条件下饲养羽化的2日龄成虫的飞行能力均有不同程度的下降。吊飞温度对草地贪夜蛾飞行能力也有影响。28℃条件下饲养羽化的2日龄成虫在5种温度下(16、20、24、28和32℃)吊飞10 h的结果显示,尽管不同吊飞温度下成虫平均飞行速度和飞行时间均具有显著差异(P<0.05),但平均飞行距离差异不显著(P>0.05),这说明草地贪夜蛾适宜飞行的温度范围较广。试验结果为揭示草地贪夜蛾迁飞行为规律及预测预报奠定了基础。

To determine the effect of temperature on the flight capacity of the fall armyworm,Spodoptera frugiperda,we investigated its adult flight capacity at different temperature in the laboratory using flight mill technique.The results showed that when the whole generation of this species was reared at the constant temperature of 20,24,28,32 and 36℃,the flight capacity of the 2-day old adults showed significant difference during 10 hours tethered flight test.The individuals reared at 24℃,28℃and 32℃have stronger flight capacity,and peaked at 32℃,with the farthest average flight distance of(29.48±2.73)km,the longest average flight time of(7.21±0.45)h,and the highest average flight speed of(4.02±0.19)km/h,respectively.Proportions of the adults flying beyond 30 km and 8 h during the test period accounted for 40%and 45%,respectively.The flight capacity decreased when S.frugiperda was reared at 20℃and 36℃,respectively.The tethered flight ambient temperatures of 16℃,20℃,24℃,28℃and 32℃also have some effect on the adult flight.Significant differences were observed in the average flight velocity and flight duration of the 2-day old adults emerged from rearing temperature of 28℃.However,no significant difference appeared in the average flight distance,suggesting wide suitable flight ambient temperatures existed in this species.Our results provided a foundation for revealing the migration regularity and population prediction in this newly invaded insect.