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.