Search

Japanese monkshood (Aconitum japonicum subsp. subcuneatum) with stem rot and root rot were found in two fields in Hokkaido and Toyama, Japan, in 2015. The isolate obtained from Hokkaido was identified as Rhizoctonia solani anastomosis group (AG)-5, and the isolate from Toyama was binucleate Rhizoctonia AG-U based on the number of nuclei, hyphal fusion reactions, and sequences of the rDNA-ITS region. The symptoms were reproduced in inoculation tests. This is the first report of stem and root rot of monkshood caused by Rhizoctonia spp. in Japan. [ABSTRACT FROM AUTHOR]

Sudden wilt and blight developed on ginseng seedlings (Panax ginseng) in Ibaraki Prefecture, Japan, in June 2017. Rootlets rotted and fell off. Aseptate hyphae were observed in this trace tissue that detached from main roots, which had orange-yellowish tinges. The white mycelium isolated from the diseased main roots was identified as Pythium myriotylum based on morphology and cox1 gene sequences. The isolate reproduced the symptoms on healthy ginseng seedlings and was re-isolated from diseased seedlings. This is the first report of seedling rot (naegusare-byo in Japanese) on ginseng caused by P. myriotylum in Japan. [ABSTRACT FROM AUTHOR]

In early January 2015-2017, anthracnose was detected on Satsuma mandarin orange (SMO) (Citrus unshiu) fruits kept in farmers’ storage rooms in Saga Prefecture, Japan. Three single-spore isolates from rotten fruits reproduced the postharvest anthracnose symptoms in wound-inoculated SMO fruits and were re-isolated from lesions. The isolates were identified as Colletotrichum fioriniae based on conidial morphology, culture characteristics, rDNA-ITS, and beta-tubulin-2 gene sequences. This is the first report of postharvest anthracnose on SMO caused by C. fioriniae. [ABSTRACT FROM AUTHOR]

Flyspeck symptoms were found on mango ( Mangifera indica L.) in Okinawa Prefecture, Japan in June 2014. Just before harvest, surfaces of fruits and green branches developed groups of tiny black dots within dark smudges. A fungus was isolated from the dots on both fruits and branches. The isolates were identified as Stomiopeltis sp. based on pathogenicity, morphology and molecular phylogenetic analyses with rDNA-ITS and LSU sequences. This is the first report of flyspeck (susuten-byo in Japanese) on mango caused by Stomiopeltis sp. in Japan. [ABSTRACT FROM AUTHOR]

The article discusses the taxonomy of pathogenic fungi found in plants on the basis of their morphology, phylogeny and host specificity. It provides details about identification and reclassification of fungal species on the basis of DNA sequences. The taxonomic status of Colletotrichum genus along with other pathogenic fungal species with reference to their respective host plants are also discussed.

In 2009, leaf spots on Mandevilla ornamental cultivars Alice Delight and Sun Parasol Milky Pink were found for the first time in Kanagawa Prefecture in Japan. Pathogens isolated from the cultivars were identified as Colletotrichum truncatum and C. siamense based on morphology and molecular data. They reproduced original symptoms on each cultivar after inoculations and were reisolated. Both pathogens were also pathogenic to both cultivars. We propose calling the disease anthracnose, 'tanso-byo' in Japanese. [ABSTRACT FROM AUTHOR]

Yellow spots on leaves of white lace flower, Ammi majus, were found in Chiba Prefecture, Japan, in October 2006. The symptoms later developed into large brown spots. Brown lesions were also observed on the lower stem, and stem rot followed. A fungus was frequently isolated from the lesions, and the symptoms were reproduced after artificial inoculation. The causal fungus was identified as Pleospora herbarum based on morphology and molecular analysis. We named the new disease 'yellow spot' ('ouhan-byo' in Japanese). [ABSTRACT FROM AUTHOR]

A preemergence damping-off of tobacco ( Nicotiana tabacum L.) was found in Fukuoka, Japan, in 2009. A fungus repeatedly isolated from the black-rotted seeds reproduced the symptoms in tobacco seeds, and the preemergence damping-off developed after flower and soil inoculation with the fungus. Brown spots and blight developed on leaves of tobacco seedlings after inoculation with the isolate. The fungus was reisolated from the rotted seeds and blighted leaves. The causal fungus was identified as Stemphylium lycopersici based on morphology and phylogenetic analysis. This is the first report to confirm the pathogenicity of S. lycopersici in tobacco in the world. [ABSTRACT FROM AUTHOR]

Severe fruit rot of sweet pepper was found in Shimane, Hyogo, Chiba, Toyama, and Nagano prefectures, Japan from 2005 to 2011. Dark, sunken spots with concentric rings of orange conidial masses appeared on fruits. Pathogenic isolates from diseased fruits in the prefectures were identified as Colletotrichum scovillei. This species was added to the pathogens of sweet pepper anthracnose in Japan. The representative isolate was pathogenic to sweet pepper, tomato and chili pepper fruits, kidney bean pod, azuki bean, pea and strawberry leaves, but a caused no symptoms on cucumber or carrot in inoculation tests. [ABSTRACT FROM AUTHOR]

Severe blight of stems was found on Madagascar periwinkle ( Catharanthus roseus) in Shizuoka and Okinawa prefectures, Japan, in July 2003 and September 2004, respectively. Similar fungi were isolated from the diseased plants. The isolated fungi caused the disease after inoculation and subsequently were reisolated from diseased tissues. The fungi were identified as species closely related to C. siamense or C. tropicale according to sequences of the β-tubulin-2 gene, indicating that they belong to the Colletotrichum gloeosporioides species complex. This is the first report specifying the genetic relationships of the pathogens of Madagascar periwinkle anthracnose in the complex. [ABSTRACT FROM AUTHOR]

A new disease found on garland chrysanthemum in Osaka, Japan in 2009 and its causal agent were identified and characterized. Light brown spots first appeared on lower leaves of seedlings, and the leaves blighted or rotted. A fungus isolated from diseased plants, described recently as Gibellulopsis chrysanthemi, was demonstrated to reproduce the natural symptoms in inoculation tests. Sufficiently long, moist periods after inoculation promoted the infection even after lengthy dry periods. The pathogen also caused the disease on chrysanthemum and lettuce, but not on seven other vegetables. The fungus caused the disease after 6 months of dry storage. The disease was termed seedling rot ('nae-fuhai-byo' in Japanese). [ABSTRACT FROM AUTHOR]

Brown spots were found on leaves of black locust ( Robinia pseudoacacia L.) in Nagano Prefecture, Japan, in August 2011. A fungus isolated from the diseased leaves reproduced the symptoms after inoculation, and was re-isolated from the lesions. The pathogen was identified as Colletotrichum nymphaeae based on morphological and molecular analyses. This is the first report of C. nymphaeae as a pathogen of anthracnose of black locust in Japan. [ABSTRACT FROM AUTHOR]