Knowing fungal infection process is critical for exploring the relationship between U. virens and rice host, also it is important to control the occurrence of the disease in rice production. Here,
we monitored the early processes of fungal infection and detected the ROS levels and callose deposition in rice floral organs upon the recognition of U. virens infection. We also examined the invasionsites at the late stage of U. virensinfection and provided evidence to show degrada- tion of the integuments of ovary may be the critical strategy for U. virens to proliferate in the infected rice spikelets.