title: Evaluation of the Effects of Light Intensity and Time Interval After the Start of Scotophase on the Female Flight Propensity of Asian Gypsy Moth (Lepidoptera: Erebidae).
abstract: Asian gypsy moth, Lymantria dispar L. (Lepidoptera: Erebidae), females are capable of flight, but little is known about what causes the variation in flight propensity that has been observed. The female flight propensity and capability of Asian gypsy moth from seven geographic populations (three from China, two from Russia, one from Japan, and one from Korea) were compared under all combinations of three light intensities (0.05, 0.10, and 0.40 lux) and during three time intervals after the start of scotophase. A total of 567 females were flight tested. Female flight propensity, time to initiate walking, fanning, and flying, and duration of fanning differed significantly among geographic populations. Females were less likely to voluntarily fly during the 0-1-h time interval after the start of scotophase than during the later time intervals (1-2 and 2-3 h), suggesting that the light intensity cue has to occur at the correct time after the expected start of scotophase for flight initiation. Light intensity did not significantly affect the proportion of females that voluntarily flew, but did impact the timing of the walking and fanning preflight behaviors. The interaction between light intensity and time interval after the start of scotophase had a significant effect on the proportion of females that fanned. The proportion of females with sustained flight capability varied among the populations evaluated. These results may aid in determining the risk of Asian gypsy moth dispersal, but further work is needed to assess other factors that play a role in flight propensity.
authors.affiliation: Beijing Key Laboratory for Forest Pest Control, Forestry College, Beijing Forestry University, - 35 Qinghua East Rd., Beijing 100083, China (chen-fang866@163.com; shi_juan@263.net).
authors.forename: Fang
authors.initials: F
authors.lastname: Chen
authors.affiliation: Beijing Key Laboratory for Forest Pest Control, Forestry College, Beijing Forestry University, - 35 Qinghua East Rd., Beijing 100083, China (chen-fang866@163.com; shi_juan@263.net).
authors.forename: Juan
authors.initials: J
authors.lastname: Shi
authors.affiliation: Northern Research Station, Forest Service, United States Department of Agriculture - 51 Mill Pond Rd., Hamden, CT 06514 (mkeena@fs.fed.us), and Corresponding author, e-mail: mkeena@fs.fed.us.
authors.forename: Melody
authors.initials: M
authors.lastname: Keena
mesh_terms: D000818:Animals; D005202:Asia, Eastern; D005260:Female; D005426:Flight, Animal; D008027:Light; D009036:Moths / Q000235:genetics / Q000502:physiology*; D017440:Photoperiod; D012426:Russia; D013997:Time Factors
keywords: Asian gypsy moth; female flight; light intensity; scotophase