Peach Latent Mosaic Viroid Isolated from Stone Fruits in Japan.

Abstract

Primer pairs and nucleic acid preparations were used with RT-PCR to detect peach latent mosaic viroid (PLMVd) from stone fruits collected across Japan. The viroid was detected from 94.3% of the peach samples, 5.3% of Japanese plum samples, 4.4% of mume samples and 3.7% of sweet cherry samples, but was not detected from European plums and apricots in local orchards in Japan. It was also detected from many peach cultivars at the National Institute of Fruit Tree Science (NIFTS), including all peach yellow mosaic- and oil blotch-infected cultivars. Symptom expression was also monitored on the RT-PCR-assayed stone fruit trees maintained at NIFTS. Only one of the peach cultivars positive for PLMVd expressed mosaic symptoms on leaves; however, the other cultivars had no symptoms. Two PLMVd isolates from peach cultivars Nakatsu Hakutou and Akatsuki in Japan were sequenced; they consisted of 337 nucleotides. The Nakatsu Hakutou isolate differed from a French isolate at 24 sites in the sequence, including 24 base exchanges, whereas the Akatsuki isolate differed at 28 sites, including 26 base exchanges, one insertion and one deletion. Two isolates showed 91 and 92% sequence homology with the PLMVd from France.