Flight Activity Of Adult Orange Wheat Blossom Midge, Sitodiplosis Mosellana(Diptera: Cecidomyiidae) And The Influence Factors

The orange wheat blossom midge, Sitodiplosis mosellana (Géhin)(Diptera:Cecidomyiidae), is a chronic wheat pest around the world. Research has shown that S.mosellana adults engage in short-distance flight but also exploit weather patterns mainly forlong-distance dispersal. However, little is known about the flight performance of S. mosellana,and the effects of the environmental factors that influence its flight activity. In this study, theeffect of temperature, light intensity, age and sex on the flight performance of S. mosellanawas explored using a26-channel, computer-monitored flight mill system. The result wouldhelp us to make a progress in wheat midges outbreak forecast.1、Both female and male S. mosellana showed stronger flight capacity than expected.The most suitable temperature for flight was16~24°C. Flight distance, duration and speedof S. mosellana significantly differed between various temperatures. Both females and malesflew the longest distance and duration at16°C,735.10m and113.41min for females, and437.54m and69.96min for males, respectively. While the greatest speed were at28°C,10.20m/min for females and9.00m/min for males. The longest flight distance of one midgefor both female and male was at16°C,2181m for females and2444.16m for males.2、The influence of age on the females and males was different. For females, the flightdistance and duration significantly differed between one and two-day-old S. mosellana, whilethe flight speed showed no significant difference. For males, one-day-old and two-day-old S.mosellana did not exhibit significant difference in flight distance, duration, and speed. Forboth females and males, the percentage of individuals that flew more than500m of one-day-old was higher than two-day-old.3、Light intensities had great effect on the flight performance of S. mosellana. Amongthe females tested in different light intensities, the distance and the duration significantlydiffered between the various light intensities, while speed showed no significant differencebetween the various light intensities. Flight distance and duration gradually declined with theincrease of light intensities, while speed gradually increased, and the fastest speed was10.80m/min. The percentage of fliers decreased with the increase of light intensities.4、There was a big difference between the flight performance of females and males.Among the S. mosellana tested, females represented stronger flight capacity than males in whether one-day or two-day-old. More than50%individuals of one-day-old females flewover500m, while only24%of males flew more than500m. For two-day-old individuals,37%of females flew over500m, while only25%of males flew over500m.