Shuichi Yamasaki, Oita Prefectural Agriculture, Forestry and Fisheries Research Center, Oita 872-0103, Japan;
Junichi Sakai, National Agricultural Research Center for Tohoku Region, Iwate 020-0198, Japan;
Shigeru Kamisoyama and
Hideyo Goto, Oita Prefectural Agriculture, Forestry and Fisheries Research Center, Oita 872-0103, Japan;
Mitsuru Okuda, National Agricultural Research Center for Kyushu Okinawa Region, Kumamoto 861-1192, Japan; and
Kaoru Hanada, National Agricultural Research Center, Ibaraki 305-8666, Japan
Go to article:
Accepted for publication 30 September 2008.
A mild isolate (designated as 10-O) of Sweet potato feathery mottle virus (SPFMV) was obtained from Ipomoea batatas. This isolate rarely caused skin discoloration and did not cause russet crack disease on the storage roots of I. batatas that are typical of infection with the severe strain of SPFMV (SPFMV-S). The yield of the 10-O--infected I. batatas ranged from 92 to 105% of the yield of healthy I. batatas. The coat protein gene of 10-O encodes 315 amino acids and has sequence identities of 91.1% at the nucleotide level and 95.6% at the amino acid level with the corresponding region of SPFMV-S. When I. batatas cuttings were inoculated with 10-O and later challenged with SPFMV-S, russet crack symptoms were much reduced and SPFMV-S was not detected in the challenged plants. These results indicate that 10-O can be an effective biological control agent against russet crack disease.
© 2009 The American Phytopathological Society