Laboratory-based flight performance of the fall armyworm,Spodoptera frugiperda

In late 2018,the fall armyworm(FAW)Spodoptera frugiperda Smith(Lepidoptera:Noctuidae)made its arrival in China and its populations have since proliferated across most of eastern Asia.While S.frugiperda exhibits a considerable dispersal capacity and engages in long-distance migration,there’s only scant information on the species’flight capability.Here,we empirically assessed S.frugiperda flight activity under varying climatic conditions using a flight mill.More specifically,under laboratory conditions,FAW exhibited superior flight performance at 20-25℃ and 60-90%relative humidity(RH).When quantifying flight performance over five consecutive nights(i.e.,10 h/night),all flight parameters initially increased and then gradually dropped and FAW adults attained a total flight distance,duration and velocity equal to 63.73 km(48.42-94.12 km)(median,quartile range),24.12 h(20.87-27.73 h)and 2.73 km h^(-1)(2.13-3.33 km h^(-1)),respectively.Our work constitutes a first comprehensive assessment of S.frugiperda flight performance and provides baseline information for future efforts to forecast spatiotemporal changes in its geographical distribution,movement patterns and invasion trajectories.Such can ultimately permit a timely and targeted deployment of area-wide pest management measures against this newly-invasive pest in China and across eastern Asia.