白背飞虱[Sogatella furcifera (Horváth)]是我国最重要的水稻害虫之一。每年6—8月高温是制约该虫在长江流域发生的重要生态因子。白背飞虱多栖息于稻丛基部,其小气候特征常不同于大气。采用变温变湿、恒温恒湿两种方式,通过分别模拟高温期间(日最高温35℃~39℃)水稻拔节后稻丛基部和大气温湿度条件,研究了高温季节稻丛基部与大气温湿度条件对白背飞虱的生长、发育和繁殖的影响。结果表明,稻丛基部温湿度条件下,白背飞虱的生长、发育和繁殖在变温变湿模拟与恒温恒湿模拟间无显著差异,白背飞虱能正常地完成生长发育和繁殖。与之相比,模拟大气条件下,白背飞虱生长、发育和繁殖相关的多数指标均受到显著抑制,其中较为重要的单雌产卵量,大气变温变湿模拟较稻丛基部变温变湿模拟减少了62.1%。可以认为,夏秋高温期间水稻拔节后稻丛基部田间小气候有利于白背飞虱“躲避”高温天气的不利影响。

The white-backed planthopper, Sogatella furcifera (Horváth), is a major pest of rice in China. The outbreaks of S. furcifera in the Yangtze River Valley were affected by natural ecological factors. For example, high temperature (over 35℃) in June and August restricted the outbreaks of planthoppers. However, under high temperature,the microclimate near the water surface of rice paddies where planthoppers inhabited were quite different from that in atmospheric environments. According to those differences, the microclimate near the water surface of rice paddies and atmospheric temperature and humidity were simulated in laboratory. Using constant and fluctuating simulated types, the laboratory experiment was performed to compare their effects on the nymph survival rate, duration of nymph stage, fresh weight of newly emerged adults, adult longevity, female fecundity and egg hatching rate of S. furcifera. Our results revealed that: 1) in case of the microclimate near the water surface of rice paddies, all the biological parameters of S. furcifera had no significant difference between the constant and fluctuating temperature and humidity, and S. furcifera successfully completed the whole life cycle;2) compared to the microclimate near the water surface of rice paddies, atmospheric conditions significantly decreased nymph survival rate, duration of female and male nymph, number of eggs per female and hatching rate, respectively. For example, an important biological parameters, the number of eggs per female reduced by 62.1%. We speculate that the microclimate near the water surface of rice paddies may allow S. furcifera to be immune to the detrimental influence of high temperature in the Yangtze River Valley.