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前文曾对稻飞虱的卵期天敌作了简单的介绍。卵期天敌的作用是相当明显的,而若虫—成虫期的天敌同样对稻飞虱的发生数量起着重要的抑制作用。稻飞虱若虫—成虫期的天敌种类繁多,下面先将其主要类群作简单的叙述,而后进一步讨论如何估计这类天敌的作用问题。若虫—成虫期天敌的重要类群一、线虫线虫的寄生率甚高。1975年上半年在翁源(翁城)调查,于水稻分蘖期至孕穗期稻褐飞虱和白背飞虱被线虫寄生的百分率平均达34.4％,抽穗期为5.6％;1975年下半年在保亭
The previous article had a brief introduction of the natural enemy of rice planthoppers. Egg enemies of the role is quite obvious, and the natural enemies of nymph - adult stage also plays an important role in the occurrence of planthoppers. Nilaparvata lugens - adult period a wide range of natural enemies, the following first of its major groups briefly described, and then further discussion of how to estimate the role of such natural enemies. Nymphs - an important group of predators in natural enemies, parasitic nematodes nematode rate is very high. In the first half of 1975 in Wengyuan (Wengcheng) survey, the percentage of rice planthopper and white-backed planthopper parasitized by the nematode at the tillering to the booting stage was 34.4% on average and 5.6% at the heading stage. In the second half of 1975,