Rice false smut is a worldwide fungal disease in rice caused by Ustilaginoidea virens (cooke) Tak, which harmed the panicles of rice and produced rice fade balls. It was all along ignored before 1980s' because of its occasionally happening on the middle- and latex-riped rice. Since 1980s', however, with the change of rice c+++++ultivars and increasing of fertilization in the paddyfield, rice false smut in China has being more and more serious, which not only influences greatly on the yield and qualit...