1发病原因1.1品种多、乱、杂,感病品种多据种子经销商不完全统计,3年以来长治各县区市场上销售的品种每年都不下百个,其中不乏有未经审(认)定的品种或虽已审定但不适宜长治地区,甚至有假冒伪劣种子。因此,整个种子市场可以说是鱼目混珠。农民在购种常识不足的情况下,选种了较多 1 pathogenesis 1.1 breeds, chaos, miscellaneous, susceptible varieties According to incomplete statistics of seed dealers, Changzhi counties in the three years since the market varieties are not less than one hundred, many of them without trial (recognized) Although the varieties have been approved but not suitable for Changzhi area, there are even fake and shoddy seeds. Therefore, the whole seed market can be described as fish. Farmers in the purchase of common sense lack of circumstances, the selection of more