水稻主栽品种和气象因素对稻瘟病田间流行的影响

摘要

The rice blast disease epidemics are closely related with the cultivated rice varieties, genetic diversity of Magnaporthe grisea and climate.Therefore, monitoring and analyzing the impacts of cultivated rice varieties and climate factors on rice blast disease will provide valuable information for rice blast control.By investigating rice blast disease on main cultivated rice varieties within Hangzhou city, we found great differences in both rice varieties and farming area during 2015-2016 year.Remarkably, Japonica rice was more susceptible to blast than indica rice.Second, the dominant japonica rice including Zhejing 88 was highly infested by rice blast in plain area.Furthermore, rice blast continuously occurred in indica rice as Zhongzheyou 1 in the eastern mountain area with high moisture and lack of sunlight.Last, rice blast severely happened at large area with multiple rice varieties in 2015, but was moderate in 2016.Based on the rice blast monitoring and climate data during 2011-2015, we mathematically analyzed the correlation between epidemic and climate factors, and modelled the correlation between epidemic and grain lost.Our results showed strong correlation among epidemic, grain lost and climate factors such as temperature, moisture, rainfall, sunlight, which had been verified to be reliable models and could be further used for the prediction of rice blast epidemic.This study suggested that adjusting rice varieties structure according to the rice blast monitoring data together with the proper prevention approaches responding to climate conditions was a useful tool for the sustainable control of rice blast disease.%为明确稻瘟病易感水稻品种和气象因素对稻瘟病田间发生流行的影响,调查分析了杭州地区2015-2016年水稻主栽品种上稻瘟病的发生情况及不同种植区的发病特点.结果表明,不同品种类型感病性有差异,粳稻总体发病重于籼稻,且不同种植区域发病特点差异较大.平原地区以浙粳88等常规粳稻发病面积较大,西部山区以中浙优1号等籼型杂交稻品种发生重.年度间发病面积也有差异,2015年发病品种多、面积大,2016年发病相对较轻.基于2011-2015年杭州地区稻瘟病发生情况及气象数据资料,对稻瘟病发生流行与气象因素的相关性进行分析,建立了稻瘟病发生及实际产量损失的预测模型,经逐步回归法分析表明,叶瘟、穗颈瘟发生面积及实际产量损失与气温、湿度、雨量、日照等气象因素均相关.经检验,3个相关性分析模型均在比较准确或准确的范围,可以应用于稻瘟病的适时、准确预报.建议稻瘟病的综合防控策略为:根据主栽品种田间抗性调整品种布局,针对山区、老病区及气候条件的变化及时预防,实现病害的可持续控制.