Group 3 is the most virulent one and may infect all ofdifferential hosts,including high resistant cultivars as Youbian 30 andKexi 8.391 SMV isolates were collected from Liaoning,Jiling and Heilong-jiang provinces of Northeast China.

• 3号株系群则对7个鉴别品种包括高抗品种诱变30及科系8号均能发病。