METHOPRENE INFLUENCES REPRODUCTION AND FLIGHT CAPACITY IN ADULTS OF THE RICE LEAF ROLLER, Cnopholocrocis Medinolis(GUENEE) (LEPIDOPTERA: PYRALIDAE)

摘要

Fuvenile hormone, (JH) influences many aspects of insect biology, including oogenesis-flight syndrome tradeoffs between migration and reproduction. Drawing on studies of many migratoiy insects, we posed the hypothesis that JH influences migratoiy capacity and oogenesis in the rice leaf roller, Gnaphalocrocis medinalis. We treated adults moths (days 1, 2 and 3 postemergenre) with the jH analog (JHA), methoprene, and then recorded the influences of JHA treatments on reproduction. JHA treatment on day Ipostemergenre, but not on the other days, shortened thepreoviposition period, although JHA did not influence total fecundity, oviposition period, or longevity. We infer day 1 postemergenre is the JH-sensitive stage to influence reproduction. Therefore,we treated moths on day J postemergenre withJHA and recorded flight capacity, flight muscte mass, and triacylglycerol (TAG) accumulation. JHA treatments did not influence flight speed, but ted to reductions in flight durations and flight distances. At day 3 posttreatment (FT), JHA-treated females flew shorter times and tess distance than the controls; JHA-treated mates, however, only flew shorter times than the controls.JHA treatments ted to reductions in flight muscte mass in femates at days 2—3 FT and reductions in TAG content in females at day 3 FT, but, these parameters were not influenced by JHA in mates. These findings strongly sujyport, our hypothesis, pom which we infer that jH is a major driver in G. medinalis oogenrsis-flight syndrome tradeoffs. Our data also reveal a jH-sensitive stage in adulthood during which jH influences the oocyte-flight syndrome in G. medinalis.