A taxonomic revision of Puccinia species causing rust diseases on sugarcane was conducted to clarify their morphological characteristics. Specimens including previously reported species, Puccinia melanocephala, P, kuehnii and Puccinia sp. sensu Muta, 1987, were collected in Japan and the Philippines and borrowed from various herbaria worldwide. Morphological characteristics of these specimens were examined under light and scanning electron microscopes. Comparative morphological studies of the specimens showed that rust fungi infecting sugarcane could be classified into two species, Puccinia melanocephala and P. kuehnii. Puccinia sp. sensu Muta was morphologically identical with P. kuehnii. Results of this study corroborate previous phylogenetic analysis results of D 1/D2 regions of LSU rDNA gene.

In March 1999, we found prairie gentian (Eustoma granditlorum) infected with powdery mildew in a greenhouse in Oita Prefecture, Japan. Morphological observation revealed that the caugal fungus belongs to the mitosporic genus Oidium subgenus Pseudoidium [teleomorph: Erysiphe semu Braun and Takamatsu (2000)l. Precise taxonomic position of the fungus, however, is uncertain due to lack of the perfect stage. We determined the nucleotide sequence of the rDNA ITS region of the fungus. Comparison of the sequence with those obtained from DNA databases of this fungal group revealed that the sequence is identical to those of powdery mildews from garden four-o'clock (Mirabilis jalapa) and broad bean (Vicia faba). Inoculation of an isolate from garden four-o'clock caused mildew on prairie gentian and broad bean, suggesting that the prairie gentian mildew originates from garden four-o'clock or broad bean. Molecular phylogenetic analysis indicated a close relationship of this fungus to Erysiphe baeumleri on Vicia spp. and E. trifolii on Trifolium pratense. From these results, we propose that prairie gentian mildew diverged from a Fabaceae-parasitic ancestor.

collected in Miyazaki with that found in Kagoshima and previously concluded that they were the same species, Colletotrichum capsici (Sydow) Butlar & Bisby, based on their morphology (Sato et al. 1999). We have since reidentified them as Colletotrichum dematium (Persoon: Fries) Grove based on their morphology and rDNA ITS-1 sequences.Symptoms. Many round, grayish green to dark brown spots 1-2 mm in diameter appear on lower leaves, and ellipsoid to fusiform and black spots are scattered on petioles and leaf vines at an early stage (Figs. 2, 3). The spots enlarge and coalesce to form light brown, irregular, large-lesions and then blight the entire leaflet (Fig. 2). The leaf blight progresses from the lower leaves to upper leaves, and whole plants develop the blight and finally fall to the ground. Numerous black acervuli with setae and milky to brownish orange masses of conidia formed on the lesions when the diseased plants were kept in moist conditions (Fig. 4). Although symptoms of Japanese radish anthracnose caused by C. higginsianum (Hagiwara and Kishi 1998) were similar to those mentioned here, damage by the present pathogen was more severe than that by C. higginsianum.Abstract Anthracnose of Japanese radish found in Kagoshima and Miyazaki prefectures was demonstrated to be caused by Colletotrichum dematium based on inoculation experiments and morphological and molecular identification of the pathogenic fungus. Although symptoms of Japanese radish anthracnose caused by Colletotrichum higginsianum were similar to those caused by C. dematium, damage by the latter pathogen was more severe than that by C. higginsianum.

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