河南省烟草黑胫病菌生理小种鉴定

在河南省宜阳、登封、渑池等15个烟叶主产区分离到烟草黑胫病菌36个，采用TTZ颜色反应和游动孢子悬浮液注射接种鉴别寄主两种方法鉴定其生理小种类型。结果表明:36个菌株在TTZ培养基上均呈现红色反应，有32个菌株对L8和NC1071都有较强的致病力，将其鉴定为1号生理小种，占供试菌株的88.9%，为河南省烟草黑胫病菌的优势小种；其他4个菌株有1个菌株对L8无致病力，2个菌株对其致病力较弱，1个菌株对NC1071无致病力，生理小种类型尚未确定。

Identification of Physiological Race of Phytophthora parasitica var. nicotianae in Henan Province

The physiological race of 36 Phytophthora parasitica var. nicotianae strains were isolated from Yiyang, Dengfeng, Mianchi and other major tobacco growing area of Henan, and identified by TTZ(2,3,5 triphenyltetrazolium chloride) color reaction and the differential host with zoospore suspension inoculation. The results showed that all of the strains presented red on TTZ medium, and 32 strains, which were highly pathogenic to the hosts L8 and NC1071, were identified as physiological race 1, it take up 88.9% in all strains, was the dominant race; the other 4 strains showed different reaction on the hosts: one strain was resistant to L8, two strains were weak pathogenic to it, one strain had no pathogenic reaction to NC1071, these 4 strains cannot be determined at present.