白背飞虱的再迁飞能力

通过室内模拟试验研究了白背飞虱经过一次远迁降落、取食不同水稻品种后的再迁飞能力。根据吊飞试验的持续飞行时间可将白背飞虱种群划分为居留型(<30 min)、迁飞型(≥30 min)、远迁型(>420 min)和再迁飞型(第二次吊飞持续飞行时间 ≥30 min)。在所测的558头白背飞虱中，再迁飞型的比率为5.7%；而在112头迁飞型个体中，再迁飞的比率为28.6%。取食不同品种的水稻对白背飞虱的飞行能力和再迁飞能力有显著影响。取食感虫水稻的白背飞虱飞行能力和再迁飞能力较强，再迁飞的比率也较高 (>5%)。吊飞前后取食常规稻与耐虫品种组合的飞虱的再迁飞时间则较短，再迁飞比率也较低；但吊飞前后均以耐虫品种饲喂的个体，反而也表现出较高的再迁飞比率和中等水平的再迁飞时间。而且，第一次飞行360 min以上的个体具有较强的再迁飞潜力。交配只对6日龄雌虫和2日龄雄虫的飞行能力有显著影响。

Re-migration capacity of the white-backed planthopper,Sogatella furcifera( Horvath )

Re_migration potential of the white_backed planthopper (WBPH), Sogatella furcifera (Horvath) after a long journey and feeding on different varieties of rice was tested and simulated with tethered flight on a set of computerized flight mill. The results revealed that WBPH in the rice cropping areas of the Yangtze River consisted of individuals with different flight characteristics, namely, the sedentary type (flight duration less than 30 min), migratory type (flight duration more than 30 min), strong migratory type (flight duration more than 420 min) and re_migratory type (2nd tethered flight duration more than 30 min). The proportion of the re_migratory type was 5.7% among all of 558 tested WBPH and 28.6% among 112 individuals of the migratory type. The flight capacity and re_migration potential of WBPH were influenced significantly by the nutritive conditions of the rice varieties. The individuals feeding on the hopper_sensitive varieties showed higher proportion of the re_migratory type (>5%) and stronger ability of migration. When fed on a less sensitive variety and a hopper_tolerance variety before and after the first tethered test, the flyer would perform poor re_migration flight and lower proportion of the re_migratory type. But the hoppers would exhibit higher proportion of the re_migratory type and medium_grade flight duration if they fed on a tolerance variety both before and after the first tethered test. The individuals with sustained flight over 360 min during the first tethered test performed higher ability of re_migration. The copulation status only affected the 6 day_old females and 2 day_old males significantly.