马铃薯晚疫病是一种流行性真菌病害。发病时期多在降雨偏多、雨量集中、相对湿度大、雾露日多的7月份。其发病后的主要症状是:叶片尖端或边缘处产生褐色病斑,病斑与健部有明显界限,呈水渍状,潮湿时病斑叶背产生白色霉层;茎部发病初期呈稍凹陷的褐色条斑,潮湿时出现白霉;薯快感病时出现不规则褐色病斑,严重时病部变软腐烂。该病发生轻者减产,重者绝收。其主要防治技术,除注意选用抗病品种外,还应结合采取以下措施:一、芽块处理播前用25%的甲霜灵或35%的甲霜灵可湿性粉剂1000倍液,均匀喷施在芽块上。尔后,堆闷2小时并经晾晒后即可播种。这样一般可推迟发 Late blight of potato is an epidemic fungal disease. More during the onset of heavy rainfall, rainfall, relative humidity, fog exposed in July. The main symptoms after the onset of the disease were as follows: the brown spots appeared on the tip or edge of the leaves, the obvious spots of the lesions and the healthy part were water stains, and the white mold layer was formed on the leaf leaves of the diseased leaves when wet; Of the brown streaks, white mold appears when wet; potato brown spots when the disease is irregular brown, severe soft rot disease department. The disease occurred in light of production cuts, those who seriously bad. The main control techniques, in addition to pay attention to the selection of disease-resistant varieties, but also with the following measures should be taken: A bud treatment before sowing with 25% metalaxyl or 35% metalaxyl WP 1000 times, uniform spray Shi bud in the block. Later, the pile stuffy 2 hours and after drying can be sown. This can be delayed in general