长江中下游稻区水稻区试品种稻瘟病的抗性评价

对2004-2008年参加长江中下游稻区和湖南省水稻区试的2 178份水稻材料的稻瘟病抗性进行了鉴定.结果表明,以综合指数作为评价指标,2 178份水稻区试材料的抗性水平差异明显,其中无抗和高抗品种;中抗品种有199份,频率为9.26%;中感品种551份,频率为25.64%;感病品种933份,频率为43.42%;高感品种466份,频率为21.68%.2004-2008年长江中下游水稻区试品种对稻瘟病的整体抗性水平呈下降趋势.以综合指数来评价水稻稻瘟病的抗性较为科学、合理,符合生产实践要求.

Evaluation of Blast Resistance of Rice Varieties in Regional Trials in Middle and Lower Reaches of Changjiang River Valley

The blast resistance of 2 178 rice varieties from the regional trials of Hunan Province and the middle and lower reaches of Changjiang River Valley was identified and evaluated during 2004 and 2008. The results showed that the resistant levels evaluated by the integrated index varied greatly with the varieties, of which none was highly resistant (HR) or resistant (R) to blast, 199 or 9.26% of the tested varieties were intermediately resistant (MR) to blast, 551 or 25.64% of the tested varieties were intermediately susceptible (MS) to blast, 933 or 43.42% of the tested varieties were susceptible (S) to blast and 466 or 21.68% of tested varieties were highly susceptible (HS) to blast. It was found that there was a decreasing trend in blast resistance for the tested varieties in the regional trials of the middle and lower reaches of Changjiang River Valley from 2004 to 2008. The integrated index was considered to be a more scientific and reasonable index to evaluate blast resistance of varieties in practical rice production.