Abstract: Highly susceptible Chinese hybrid rice gave significant impact on the insect pest ecology. The brown planthopper (BPH), Nilaparvata lugens, and the whitebacked planthopper (WBPH), Sogatella furcifera, have raised as the most prominent outbreak-prone pests of Chinese hybrid rice. Although WBPH was only a secondary insect pest of rice in China before 1970s, it increased greatly in the hybrid rice areas in 1980s. WBPH also became an economic insect pest of japonica rice in Central China due to its massive displacement from hybrid rice area in South China. BPH was temporally suppressed by the hybrid rice with the Bph 1 gene for BPH-resistance. However, the BPH adapted to them by shifting biotype, when the resistant hybrid rice spread over the insect migration zone in South- and Central China. After 1990, previously BPH-resistant hybrid rice became highly susceptible to BPH. Lack of major genes for resistance does not account enough for the hyper- susceptibility of Chinese hybrid rice to the planthoppers. Heterotic vigorous growth of hybrid rice might be partially responsible for the enhanced fecundity of the planthoppers. Hyper-susceptibility of Chinese hybrid rice to the rice planthoppers is primarily inherited from the WA-CMS lines. Thus, CMS lines are needed to improve insect pest resistance in hybrid rice. Utilization of durable and multi-resistant IR varieties like IR64 as restorer lines might be an alternative approach to improve hyper-susceptibility of Chinese hybrid rice to insect pests.The striped stemborer, Chilo suppressalis and the yellow stemborer, Scirpophage incertulas also increased on Chinese hybrid rice, which is more favorable as their food plants and more tolerant to their infestations than inbred rice. Yield loss assessments, with special reference to the plant compensation to the stemborer infestation, and ecological interactions between stemborers and hybrid rice are needed to evaluate actual impact of and practical field resistance to stemborers in hybrid rice.

Key words: Chinese hybrid rice, insect resistance, whitebacked planthopper, brown planthopper, striped stemborer

摘要： 介绍了高度感虫的中国杂交稻推广带来水稻害虫生态地位发生的变。褐飞虱和白背飞虱上升为杂交稻上最突出的极易爆发成灾的重要害虫。20世纪70年代以前，白背飞虱只是水稻上的次要害虫，但80年代以来其种群大大增加。由于它从中国南部杂交稻种植区大范围迁飞，白背飞虱也成为中国中部地区粳稻上的重要害虫。由于种植具有抗褐飞虱基因[i]Bph1的杂交稻组合，褐飞虱种群曾得到暂时的控制。然而，抗虫性的杂交稻在中国中部和南部稻飞虱迁飞区推广以后，褐飞虱生物型发生了改变，对抗虫品种产生了适应性。1990年以后，以前表现抗虫的杂交稻变得高感褐飞虱。缺乏抗虫性主基因不是中国杂交稻对稻飞虱超感性的充分理由，杂交稻旺盛生长的杂种优势可能是稻飞虱生殖力提高的部分原因。中国杂交稻对稻飞虱的超感虫性是从不育系遗传而来的。因此，杂交稻抗虫性的提高有赖于不育系的改良。利用持久抗性和多抗性的IR品种如IR64作为恢复系是改善中国杂交稻的超感虫性的一种有效方法。杂交稻上二化螟和三化螟为害也有所增加。与常规稻相比，杂交稻是一种更有利的食料植物且耐虫性更强。进行水稻产量损失的估计，尤其是水稻本身对螟虫为害的补偿能力，以及螟虫和杂交稻之间的生态学关系的研究有助于评价杂交稻对螟虫田间抗性的实际影响。

关键词: 中国杂交稻, 抗虫性, 白背飞虱, 褐飞虱, 二化螟, 三化螟