Abstract:
The rice blast disease caused by
Magnaporthe oryzae could lead to the significant reduction in rice production, by 40%-50% in severe cases, which threatened the global rice production and food security. However, there were few reports about the effect of
Magnaporthe oryzae on rice quality. The distribution of rice blast resistance genes in the genome of Changxiangjing 1813, a disease-resistant fragrant and soft rice variety, was identified. After the inoculation of Magnaporthe oryzae, the observation of seeds at the maturation period and the detection of thousand-grain weight and the ratio of length to width, the processing quality parameters of rice, such as the brown rice rate, milled rice rate, chalkiness degree and chalky percentage, as well as the changes of total protein, total fat, total starch and amylose contents were further analyzed. The results showed that the genome of Changxiangjing 1813 contained the rice blast resistance genes of Pid2, Pid3 and
Pib. After being infected by
Magnaporthe oryzae, the shriveled grains appeared at the top of the panicle of Changxiangjing 1813, and there were obvious brown spots on the surface of the grains in the middle and lower parts. The thousand-grain weight decreased significantly, and the ratio of length to width increased significantly. After the infection with
Magnaporthe oryzae, the rice was dark and yellow in color, and the brown rice rate and milled rice rate was significantly decreased, while the chalky percentage was increased. Moreover, the content of total protein was significantly increased, and the contents of total fat, total starch and amylose were significantly decreased. These results indicated that the
Magnaporthe oryzae had significant effect on the seed/rice yield and quality of Changxiangjing 1813.