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

(1)在9个州的大豆（甘氨酸）、葛根和大豆的叶片上采集到脲孢子和远孢子；茨城县、千叶县、神奈川县、静冈县、冈山县、爱媛县、高知县、福冈县和熊本县。(2)从茨城县、千叶县、静冈县和熊本县的uredinio孢子培养物中分离出12株单孢菌，用于生理小种的鉴定研究。根据AVRDC（1985）对台湾地区大豆锈病品种鉴定的11个大豆锈病差异品种的侵染类型，鉴定出6个不同的品种。其中一个小种在11个差异品种上的侵染类型表现出与台湾小种相同的模式。在熊本县的栽培大豆和千叶县的栽培大豆上发现了相同的小种。这表明，至少有一个大豆锈病小种在日本广泛分布，同一种群可能同时利用大豆和白叶锈病作为寄主植物。(3)大豆、p.o lobata和g.o soja上的遥孢子和远孢子形态观察结果与Ono et al.（1992）对厚根Phakopsora pachyrhizi的描述吻合较好。因此，本研究中使用的真菌被鉴定为厚根菌。(4)在大豆、大豆和肉苁蓉的幼嫩叶片上接种由真菌的端孢子覆盖产生的担子孢子。然而，没有感染的迹象。在大豆生长箱中诱导端孢子形成的尝试均不成功。

(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.