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在白菜的生产中,尤其在不利生长的条件下,极易感染病毒病、霜霉病和软腐病,使白菜严重减产,成了障碍白菜丰产的三大病害。现将其发生及防治简述如下,供参政。 1.病毒病发病条件:白菜喜冷凉、怕炎热,苗期虽然对高温有一定的适应性,但温度过高,易造成幼苗吸呼强度剧增,光合产物被大量消耗,幼嫩的根系易被高温烧伤,使幼苗瘦弱,抗病能力下降。同时在高温干旱条件下,传播病毒的蚜虫活动猖獗,容易使留种的青菜、大白菜及车前草、荠菜等杂草上的
In the production of cabbage, especially under adverse growth conditions, highly susceptible to viral diseases, downy mildew and soft rot, so that cabbage serious yield, has become a barrier to cabbage yield of the three major diseases. Now its occurrence and prevention are summarized as follows for political participation. 1. Virus disease conditions: cabbage hi cold, afraid of the heat, although the seedling has some adaptability to high temperatures, but the temperature is too high, easily lead to sharp increase in the intensity of seedlings breathe, photosynthetic products are consumed in large quantities, young roots Easy to be burned at high temperature, seedling emaciated, disease resistance decreased. At the same time in high temperature and drought conditions, the spread of virus aphids rampant, easy to make the remaining vegetables, Chinese cabbage and plantain, shepherd’s purse and other weeds