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主要病虫害生理性病害一、肉质根开裂。常在中后期发生,多沿肉质根纵向开裂,裂口较深,长度不一。严重时,裂口由根头部开始,纵贯全根。也有的在靠近叶柄处横裂,或在根头处放射状开裂。开裂的肉质根易感软腐病,不耐贮藏。二、萝卜歧根。萝卜的肉质根出现一个或几个分叉。发生原因是主根生长点受到破坏或生长受到抑制,如土质过于坚硬或土壤中有石块,或肉质根先端被未腐熟的粪肥烧伤,或被地下害虫咬伤,从而造成侧根膨大,形成歧根。侵染性病害一、白锈病。主要发病部位是叶片。发病时叶片背面生出许多稍隆起的白色疱斑,表面光滑,略有光泽,后期疱斑表皮破裂,散出白色粉末状物。在与疱斑相对应的叶片正面,产生淡黄色或黄绿色病斑,无明显边缘。二、霜霉病。
The main pest physiological diseases, fleshy root cracking. Often occur in the late, along the fleshy root longitudinal cracking, deeper cracks, different lengths. In severe cases, the gap begins with the root head and runs through the roots. Others are near the petiole at the transverse crack, or in the root radial rupture. Cracking fleshy roots susceptible to soft rot, intolerance storage. Second, radish stubble. Radish fleshy roots appear one or several forks. Occurred because the growth of the main root damage or growth is inhibited, such as soil is too hard or stone in the soil, or fleshy root tip is not matured manure burns, or bites by underground pests, resulting in lateral root enlargement, the formation of stubble . First, white rust disease. The main site of disease is leaves. When the incidence of leaves back to give birth to a number of slightly elevated white blister spot, the surface is smooth, slightly shiny, late blister epidermis rupture, scattered white powder. Blister spot in the leaves corresponding to the front, resulting in pale yellow or yellow-green lesions, no obvious edge. Second, downy mildew.