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An unknown stem rot of pitaya (H. undatus; Cactaceae) was observed in orchards in Okinawa, Japan in 2005. A Gilbertella species was isolated from diseased stems, and typical symptoms were reproduced after inoculating wounded stems with isolates. The causal fungus was identified as G. persicaria (Eddy) Hesseltine on the basis of morphological characteristics, growth and germination temperature, and rDNA-ITS sequence homology. The name Gilbertella stem rot (Kukigusare byo) was proposed for this new disease.

A new disease of carrot (Daucus carota L.) caused by Rhizoctonia solani was found in Tokushima Prefecture in 2003 and 2004. Isolates of R. solani were obtained from carrot seedlings with damping-off. Typical damping-off symptoms observed in fields were reproduced on seedlings grown from carrot seeds sown in soil amended with these isolates. The causal agent was identified as R. solani AG-4 HG II by hyphal anastomosis grouping and cultural morphology. We proposed the name of the disease as “seedling damping-off of carrot.”

A new bacterial disease has been observed on mioga (Zingiber mioga (Thunb.) Rosc.) since 1999, in Kochi Prefecture, Japan. Leaves wilted, curling under toward the center of midrib, yellowed, and the whole plant finally died. Bacterial exudate was observed at the cut edges of the pseudostem. The creamy-whitish bacteria that were isolated were pathogenic to mioga and ginger and were identified as Ralstonia solanacearum race 4 strains biovar 4 based on bacteriological characteristics. The name bacterial wilt of mioga is proposed for the disease.

1993年,新潟県白根市のセイヨウナシ‘ル・レクチエ’圃場において,芽の腐敗や葉に淡褐色～黒色の不整形斑点を生ずる病害が発生した.葉では, 5月下旬頃から小黒斑点の病斑が出現し始め, 7月下旬以降急増した.また激しい場合,病斑は拡大し落葉した.同様の病害は,セイヨウナシ‘ゼネラル・レクラーク’にも確認された.病斑部からは高率にAlternaria属菌が分離され,分生子の形態的特徴および培養性状から,本菌はA. alternata (Fries:Fries) Keisslerと同定された.本菌を‘ル・レクチエ’葉に噴霧接種した結果,葉の斑点病徴が再現され,接種菌が再分離された.また,本菌の接種により品種間差異を検討したところ,‘ゼネラル・レクラーク’,‘ル・レクチエ’が感受性で,‘バラード’,‘‘越さやか’‘ラ・フランス’,‘マルゲリット・マリーラ’,‘シルバーベル’およびニホンナシの‘二十世紀’は抵抗性であった.本菌によるセイヨウナシの病害は初めての報告であり,本病害をセイヨウナシ黒斑病(black spot of European pear)と称することを提案する.

A new disease of quince with fruit spots and brown flecks on leaves was found in Aomori. A species of Cylindrosporium was isolated from the fruit spots, and Mycosphaerella type pseudothecia were obtained from overwintered, affected leaves. Single-spore isolates from the pseudothecia produced a Cylindrosporium anamorph on potato dextrose agar. These isolates caused the same spots on quince and apple fruits and the blown flecks on quince leaves in inoculation tests. Based on morphological and cultural characteristics, the fungus was identified as Mycosphaerella pomi (anamorph: Cylindrosporium pomi). This is the first report of M. pomi on quince in Japan.

1990年,青森県三戸地方のセイヨウナシ圃場において,果実に黒色の小斑点が多数生じる病害が発生した.病斑部からは高率にCylindrosporium属菌が分離された.また1998年,同病害が多発した圃場において,葉に紫褐色∼黒褐色の斑点がみられ,翌年1999年5月に越冬した罹病落葉の斑点部にMycosphaerella属菌の偽子のう殻の形成が確認された.偽子のう殻に形成された子のう胞子の単胞子分離菌は培地上でCyliudrosporium型分生子を生じた.この分生子をセイヨウナシ果実に無傷接種した結果,黒色小斑点病徴が再現され,接種菌が再分離された.リンゴ果実に接種した場合,黒点病を生じた.またリンゴ黒点病菌をセイヨウナシ果実に接種した結果,黒色小斑点症状が生じた.本菌は形態的特徴および培養性状からMycosphaerella pomi (Passerini) Lindau(アナモルフ:Cylindrosporium pomi Brooks)と同定される.本菌によるセイヨウナシの病害としてはじめての報告である.本病害をセイヨウナシ黒点病(Mycosphaerella fruit spot)と称することを提案する.

A new disease of eggplant was found in greenhouses in Kochi Prefecture, Japan in 1996. Numerous black pycnidia were produced on brown lesions that developed from the cut surface of lateral shoots. Pycnidia were ostiolate, subglobose to pyriform, and averaged 301×248μm. Conidia were born mostly holoblastically on sometimes branched conidiophores, hyaline, aseptate, oblong to fusiform, 13.8-20.0×4.4-5.6 (mean=17.2×5.0)μm, with a truncate base. The fungus was identified as Fusicoccum aesculi on the basis of its characteristics. The symptoms were reproduced by wound inoculation, and the fungus was re-isolated. Stem blight of eggplant was proposed for the name of the new disease.

1995年8月,東京都東村山市の施設でペチュニア(Petunia×hybrida Vilm.)に,花や茎葉が急速に腐敗する激しい障害が発生した.初め花弁に水浸状の病斑が生じ,すぐに腐敗して萎れ,次いでがく,茎,葉へと急速に進展し,暗緑色水浸状に軟化腐敗し,茎枯れ,葉枯れを起こした.罹病部には小虫糞状の微小な黒粒(単胞子性胞子のう)と汚白色の菌糸が豊富に形成された.この黒粒は,灌水マット上や地表面の花殻にも認められた.罹病部からは,PDA培地上で,白色から黄褐色をおびた汚白色となり,黒色の小粒を菌そう全面に散生する糸状菌のみが分離された.分離菌株を接種したペチュニア,エンドウおよびオシロイバナは,自然発生のペチュニアの場合と同様の病徴と標徴を示し,罹病部からは接種菌が再分離された.病原菌は単独培養で,単胞子性胞子のうと胞子のう胞子を,IFO 5985菌株との対峙培養で接合胞子を形成した.接種試験の結果および形態的特徴から,病原菌をChoanephora cucurbitarum (Berkeley & Ravenel) Thaxterと同定した.病原菌の菌そう生育は10∼40°Cで認められ,適温は30°C付近であった.本病をペチュニアこうがいかび病(Choanephora blight of common garden petunia)と命名することを提案する.

Soft rotten fruits of balsam pear were found in orchards of Kanagawa and Okinawa prefecture, Japan in 2004 and 2005, respectively. The causal bacterium was identified as Erwinia carotovora subsp. carotovora according to its bacteriological characteristics. The name soft rot (Nampu byo) was proposed for this new disease.

A new disease causing purple spots on leaves of candelabra aloe (Aloe arborescens Mill.) was found in Tahara-cho and Irako, Atsumi Peninsula, Aichi Pref. in October 1993. A species of Fusarium was isolated from lesions of many infected plants. This fungus was found to be pathogenic on A. arborescens by inoculation of wounded and intact leaves. The fungus was identified as Fusarium phyllophilum Nirenberg et O'Donnell on the basis of cultural and morphological characteristics. The disease was also observed at every location examined in Boso, Miura, Kii, Osumi, and Satsuma Peninsulas, where the climate is similar to that in Atsumi Peninsula. Four additional isolates from Jogashima Island were also identified as F. phyllophilum. This is the first report of the disease on A. arborescens in Japan.

A new disease of wax gourd (Benincasa cerifera Savi) characterized by scab of fruit was observed in Okayama Prefecture, Japan in July 2003. Fungal isolates frequently obtained from diseased fruits of the plants were identified as Rhizoctonia solani AG-4 HG-I based on hyphal anastomosis and cultural morphology. In inoculation tests, these isolates were pathogenic on fruits of wax gourd and caused the same symptoms, and were re-isolated from the lesions of the diseased fruits. This is the first report of a fruit disease of wax gourd caused by R. solani. Therefore, the name brown scab of wax gourd is proposed for the new disease.

ビワ果実には苞の先端から果頂部に向かって果面にかすり状の縦すじが発症することから,栽培者間でたてぼや症と称されている症害があり,その原因を明らかにした。本症の発症果面部位を走査電顕で観察した結果,ビワサビダニ(Aceria sp.)の食害痕とともに糸状菌とくにBotrytis sp.の分生子や菌糸が多数観察された。発症果から優占的にBotrytis sp.が分離されるとともに,苞内にはビワサビダニが多数生息していた。本症状は発育途中で苞を人為的に除去した場合発症がみられなかった。ビワの苞内およびたてぼや症発症部位から分離されたBotrytis sp.をビワサビダニが生息する苞内に分生子懸濁液で注入接種するとたてぼや症が再現された。よって,たてぼや症の発現は苞内でのBotrytis sp.とビワサビダニの共存,増殖に起因すると結論される。たてぼや症の発症果面部位から分離されたBotrytis sp.は形態,培養的性質,病原性などから,ふつうの灰色かび病菌Botrytis cinerea Pers.: Fr.と同定された。

A new bacterial wilt was found on balsam pear (Momordica charantia L.) in Okinawa, Japan in October 1999. The causal bacterium was identified by its bacteriological characteristics as Ralstonia solanacearum, and the name “bacterial wilt” was proposed for the disease.

Web-blight of European pear (Pirus communis L. var. sativa de Candolle cultivar ‘Passe Crassen’ and ‘La France’) occurred in Okayama Prefecture, Japan, in July of 1989 and in October of 1993, respectively. The pathogen obtained from infested leaves and sclerotia was identified as Rhizoctonia solani AG1-IB in respect to hyphal anastomosis and culture's types. The common name of Web-blight (“Kumonosubyo” in Japanese) is proposed for this new disease of European pear.

A new disease of basil (Ocimum basilicum L.) caused by Corynespora citricola broke out in Okinawa prefecture in 2000. We propose the name of Corynespora black stem and root rot disease of basil.

A new disease of tomato with yellow mosaic symptoms was found in Japan in 1983. A strain of alfalfa mosaic virus (AMV-T), proved to be the causal agent of the disease, was characterized comparing with another isolate of AMV from red clover (AMV-R). The two isolates varied in symptomatology in tomato, pea and petunia. Neither of the isolates affected soybean which is susceptible to many strains of AMV. AMV-T and AMV-R were slightly different from each other in polyacrylamide gel electrophoresis of double-stranded RNAs extracted from Nicotiana glutinosa plants infected with the two isolates, indicating that they had distinct electrophero-types. In agar gel diffusion using anti-AMV-T serum, a spur was formed, which was not formed in a test using anti-AMV-R serum, indicating that these two isolates were serologically related but antigenically different.

In 1996, a new disease of glaucidium (Glaucidium palmatum Sieb. et Zucc.), causing stunt and witches' broom, occurred in Fukushima Prefecture. Electron microscopy revealed the presence of numerous phytoplasma particles in the sieve tubes of diseased plants. The pathogenic phytoplasma was transmitted by the leafhopper, Scleroracus flavopictus, with 22 species of plants in 10 families being infected after an inoculation test with S. flavopictus. Restriction fragment length polymorphism (RFLP) analysis of PCR-amplified 16S rDNA indicates that the pathogenic phytoplasma is closely related to gentian witches' broom phytoplasma and should be assigned to Western-X disease phytoplasma group. “Glaucidium witches' broom” was proposed for the disease.

An unknown leaf blight of the tea plant was found in Kagoshima and Shizuoka Prefectures, Japan, in the spring of 1984 and 1985, respectively. The lesions were reddish to greenish brown in color, almost round in shape and zonate. The causal fungus was identified as Ceuthospora lauri (Greville) Greville on the basis of the morphological characteristics and the pathogenicity onto the tea plant. Brown zonate leaf blight was proposed as the common name of the disease. The present fungus was isolated for the first time in Japan.

In recent years, a yellow patch in turf-grass, which is probably the symptom of a new disease, has been observed in various districts of Japan. From the lesions of leaf and stem rot, binucleate Rhizoctonia was isolated and identical symptoms were reproduced in an inoculation test. The fungus did not fuse with the representative isolates of other anastomosis groups of Rhizoctonia spp. Two out of eleven isolates of this fungus developed the perfect state when the soil-on-agar culture method was applied. The perfect state of this fungus was identified as Ceratobasidium cornigerum (Bourdot) Rogers. It is proposed that this disease caused by C. cornigerum [anamorph binucleate Rhizoctonia AG-Q] would be designated as one type of ‘hagusare-byo’ of turf-grass.

A new disease of chinese cabbage has been observed since 1966, and the occurrence area has been gradually increasing every year.The leaves of the diseased plants turn blight yellow in color, and the plants are a little stunted. These plants do not form compact central heads even near a harvest time. Their roots and stems become dark brown or blackened in the vascular tissues.Hyphae were always observed in the vascular tissues of the diseased plants. Fusarium oxysporum, the suspected causal fungus, was never isolated from the freshly dissected stem or root tissues of the diseased plants. Cephalosporium sp. was one of the most frequently isolated fungi, but its pathogenicity onto chinese cabbages was not positive. Verticillium albo-atrum is another frequently isolated fungus. It showed pathogenicity onto 3 varieties of chinese cabbages tested under a greenhouse condition at 20C. The symptoms of the plants grown in artificially infested soils were more or less identical with those in naturally infested soils. In addition, V. albo-atrum was recovered from the diseased plants. Vascular discoloration of the roots or the stems were generally observed in some 40 days after seeding in the artificially infested soil at 20C.As Verticillium disease of chinese cabbage in nature appears not to have been previously reported, this plant may be included as a new host of this fungus. “Yellows” (Japanese name, Ohkabyo) may be coined to this new disease.