农业气象因素影响稻瘟病发生分子机制初探

水稻是我国重要的粮食作物,由子囊菌(Magnaporthe oryzae)所引起的稻瘟病是水稻生产活动中的重要限制因子之一,每年给水稻生产造成巨大的经济损失。随着水稻及稻瘟菌全基因组测序工作的完成,水稻和稻瘟菌间的互作机制已日渐明朗。水稻对稻瘟菌的抗性主要来自于自身体内天然免疫机制对病原菌入侵的有效阻止,同时病原菌能够通过抑制水稻的基础免疫从而使易感水稻品种致病。稻瘟病的爆发和流行需要具备3个必要的条件:易感水稻品种、致病的稻瘟病菌群以及适宜致病的气象因素。因此气象因素是控制稻瘟病爆发和流行的一个十分重要的因素。本文立足于近年来的研究成果,从稻瘟菌侵染过程、稻瘟病发病过程及特征、水稻抗病机理等方面对水稻和稻瘟菌的互作机制进行了综述,同时分析了温度、光照、湿度等气象因素对稻瘟病菌致病和水稻抗病的影响,并初步对其影响稻瘟病爆发和流行的分子机制进行探讨,以寻求防治和控制稻瘟病发生、发展的最佳方法,为合理防控稻瘟病提供理论依据和帮助。

A preliminary study on the effect of agro-meteorological factors on molecular mechanism of rice blast occurrence

Rice is an important food crop in China. Rice blast, a disease caused by ascomycetes (Magnaporthe oryzae), is one of most limiting factors of rice production in the country, which results in huge economic losses to the rice production each year. With the completion of whole genome sequencing of rice and M. oryzae, the interaction mechanism of rice and M. oryzae has become much clearer. Resistance to rice blast fungus can effectively prevent the invasion of pathogenic bacteria through the natural immune system of rice. Also pathogens can cause diseases in susceptible rice varieties by inhibiting innate immune system of rice. Outbreaks of rice blast and popular occur under three necessary conditions — susceptible rice variety, pathogenic bacteria and pathogenic meteorological factors. Thus the meteorological factors for the outbreak and epidemics of rice blast play an important role. Based on research achievements in recent years, this paper summarized the interaction mechanism of rice and M. oryzae from the pointing of pathogenic process of M. oryzae and rice resistance, discussed the effects of temperature, illumination, humidity and other meteorological factors on the pathogenesis of M. oryzae and disease resistance of rice. The paper further explored the molecular mechanism of invasion of rice blast epidemic caused by the factors, expecting to find the best ways for preventing and controlling rice blast. Finally, the paper provided theoretical evidences in support of proper prevention and treatment methods of rice blast.