PROBLEM TO BE SOLVED: To provide a highly safe method controllable of controlling mosaic diseases caused by pepper mild mottle virus (PMMoV) in genus Capsicum plants without using methyl bromide (an ozone depleting substance with its use to be banned at the end of 2012 year and thereafter) as a soil fumigant.SOLUTION: An attenuated virus of pepper mild mottle virus (PMMoV) characterized by including, in the genomic RNA, RNA encoding an amino acid sequence having a specific mutation in 130 kDa viral replication enzyme is provided. A genus Capsicum plant with resistance to PMMoV infection, obtained by inoculating the attenuated virus thereto, and a method for controlling PMMoV mosaic diseases, characterized by comprising inoculating the attenuated virus to a genus Capsicum plant, are also provided.