Identification of physiologic races of soybean rust in Japan and ecology and taxonomy of the fungus.

(1)在以下9个县的大豆（Glycine max）、野葛（Pueraria lobata）和大豆（G.soja）的叶片上收集了脲孢子和冬孢子：茨木、千叶、神奈川、静冈、冈山、爱媛、高知、福冈和熊本。它们作为干燥的植物标本保存在我们的研究所，新鲜的夏孢子也保存在深冻室（-80 ℃）中。(2)从茨木、千叶、静冈和熊本县收集的夏孢子培养物中获得了该真菌的12个单囊群分离物，并用于生理小种鉴定的研究。根据1985年台湾大豆锈菌鉴定所用的11个鉴别品种的侵染类型，鉴定出6个不同的小种。其中一个小种在11个鉴别品种上表现出与台湾小种相同的侵染类型。在熊本县的栽培大豆和千叶县的野山大豆上也发现了相同的小种。这表明，大豆锈菌至少有一个小种在日本广泛分布，同一种群的锈菌在自然界中可能同时以大豆和野葛为寄主植物。(3)大豆、裂叶大豆和大豆上夏孢子和冬孢子的形态观察结果与Ono等（1992）对豆薯层锈菌的描述非常吻合。因此，在本研究中使用的真菌被确定为P. pachyrhizi。(4)用裂叶泡绵病菌冬孢子产生的担孢子接种大豆、大豆和多花泡绵的幼叶。然而，没有感染的迹象。在生长箱中培养的大豆上诱导冬孢子形成的尝试没有成功。

(1) Urediniospores and teliospores were collected on leaves of soybean (Glycine max), Pueraria lobata, and G.soja in the following 9 prefectures ; Ibaraki, Chiba, Kanagawa, Shizuoka, Okayama, Ehime, Kochi, Fukuoka, and Kumamoto. They were deposited as dry herbarium specimens in our institute and also fresh urediniospores were stored in a deep freezer (-80 C).(2) Totally 12 single sorus isolates of the fungus were made from urediniospore cultures collected in Ibaraki, Chiba, Shizuoka, and Kumamoto prefectures and were used for studies on identification of physiologic races. Based on infection types on 11 differential varieties of soybean rust used by AVRDC (1985) for race identification of soybean rust in Taiwan, 6 different races were identified among them. One of the races showed the same pattern of the infection types on the 11 differential varieties as one of the Taiwan races. The same race was found on cultivated soybean in Kumamoto Prefecture and on P.lobata in Chiba Prefecture. It suggests that at least one of the races of soybean rust distributes in wide area in Japan and the same population of the fungus may be able to use both soybean and P.lobata as host plants in nature.(3) Results of the morphological observation of urediniospores and teliospores on soybean, P.lobata, and G.soja, fitted well with description of Phakopsora pachyrhizi by Ono et al. (1992). Thus, the fungus used in the present study was identified as P.pachyrhizi.(4) Young leaves of soybean, G.soja and Meliosma myriantha were inoculated with basidiospores produced from overwnitered teliospores of the fungus formed on leaves of P.lobata. However, there was no sign of infection.Attempts of inducing teliospore formation on soybean grown in a growth cabinet were unsuccessful.