1999年7月山形県鶴岡市で鉢植しているベンケイソウ科の多肉植物Graptopetalum paraguayense(N.E.Br.)E.Walth,園芸名「おぼろづき」の葉身に軟腐症状が発生した.その後葉身全体が軟化腐敗して落下し,隣接葉,茎にも拡大,進展して株全体が倒伏した.本症状の病原学的調査の結果,本症は野菜類軟腐病菌と同種のErwinia carotovora subsp. carotovoraによるこれまで未記載の新病害であることが判明し,多肉植物G.paraguayense,「おぼろづき」の軟腐病(Bacterial Soft Rot)と命名した.
- 著者
- 生井 恒雄 山中 達
- 出版者
- 日本植物病理学会
- 雑誌
- 日本植物病理學會報 (ISSN:00319473)
- 巻号頁・発行日
- vol.48, no.4, pp.466-470, 1982-09-25
This investigation was carried out to determine the appearance of variants in virulence by pairing-inoculation of 2 different pathogenic isolates (races 047 and 303) of rice blast fungus, Pyricularia oryzae Cavara, on both agar media and rice leaves. The mycelium-joining method on media, and the methods of the punch-inoculation of mixed spore suspension and the pairing-inoculation on leaves using the above 2 parent isolates, induced to arise some variants having virulence different from that of the parent isolates. These variants were divided into 2 groups ; one contained the isolates (races 337, 317, 313, 137 and 037) that newly acquired the strong pathogenicity for 2 rice varieties, Kanto 51 and Tsuyuake, to which the parent isolates were non-pathogenic, and the other contained the isolates (race 347) that had both pathogenicity of the parent isolates. On the other hand, no variants in virulence appeared from the parent isolates. The race 337 isolate arised in both experiments on agar media and rice leaves. In addition, the variants were divided into 3 groups by the colony type and the color of culture on potato decoction agar medium. Thus, it was suggested that the variants in this experiment might be resulted from the anastomosis of the parent isolates.