1.寄主范围 1989年秋季经系统调查,发现黑痣病的寄主已有六种,发病较严重的是偃麦草、狗尾草、金穗狗尾草(表1)。 2.病害为害程度根据被害株病斑在茎叶上的分布面积及数量分为5级:全株无病为0级;叶片上有3个以下病斑或茎部病斑占主茎面积5％以下为1级;叶片上有4～7病斑或茎部病斑占主茎面积5～20％之间为 1. Host Range In the fall of 1989, a systematic survey found that there are six host disease black mole disease, the incidence of more serious is the thinopyrum, Setaria, Golden Setaria (Table 1). 2. Degree of disease damage According to the diseased spots on the leaves of the distribution area and quantity is divided into five levels: the whole plant disease-free to 0; leaves on the following three lesion or stem lesions accounted for the main stem area 5 % Below a level; leaves 4 to 7 lesions or stem lesions accounted for 5 to 20% of the main stem area