褐飞虱越冬种群和田间种群的致害性比较

 比较研究了当年采自田间的褐飞虱种群与上一年虫源在室内越冬繁殖种群对不同抗虫品种的致害性差异。结果表明室内越冬种群和田间种群对水稻苗期的致害性相同，均表现为明显的生物型2特性。高龄若虫对不同抗性品种TN1、IR26和ASD7的选择性无显著差异，但均以ASD7的最低。室内种群在3个品种上的若虫历期均比田间种群短2～3 d，但同一种群在不同品种之间的若虫期存活率和历期的差异不明显。

Virulence Comparison of Brown Planthopper Populations from Paddy Field and Overwintered in Greenhouse

The virulence characteristics of brown planthopper, Nilaparvata lugens Stal, from paddy field population and greenhouse population collected in late rice field last year was compared. The results showed that those two populations could infest successfully the resistant rice variety IR26 bearing resistant gene Bph1, implying the characters of biotype 2. No significant differences in nymphal feeding preference, survival rate and duration among feeding the various resistant rice varieties TN1, IR26, and ASD7 were found.