Research on Advance of Rice False Smut Ustilaginoidea virens (Cooke) Takah Worldwide: Part I. Research Status of Rice False Smut

Since hybrid rice was planted, rice false smut (RFS) caused by Ustilaginoidea virens (Cooke) Takah has risen from a sporadic secondary disease to a major devastating and common disease, due to the changes in climatic conditions, cultivation system, fertilization and water management and cultivar replacement, and has become one of the new three major rice diseases in China. In addition to cause rice yield decrease and economic losses, RFS also causes toxic effects on humans and animals, due to the fact that the pathogen has color, produces toxins, affects rice appearance, and reduces rice quality. Therefore, RFS has attracted great attention from various governmental agencies, research institutions and scientists. More than 300 papers related to RFS composed over the past 100 years were reviewed. In this part, the occurrence, epidemiology of RFS, the relationship between occurrence sverity of RFS and yield loss, field distribution pattern and sampling method of RFS and disease severity classification were discussed.