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大蒜是一种重要的蔬菜,大多采用秋播栽培,从出苗到生长期发生的病害种类较多,特别是在连作条件下病害发生重,现将几种主要害虫的症状及防治方法介绍如下:叶枯病。该病是一种真菌性病害,可危害大蒜叶片、叶鞘苔茎等部位,发生区域广、危害严重,造成蒜株早枯,蒜蔓腐烂,流行成灾年份造成减产50%~80%左右。发病症状可分为5种类型:一是尖枯型。多发生在越冬期和早春,病株叶尖变成枯黄色或深褐色,坏死卷曲。湿度大时叶尖坏死部位长出黑色霉层,少数叶片生有不太明显的紫褐色斑纹。坏死处常向叶片中部扩展,严重的致全叶黄枯。二是条斑型。多发生在越冬期和早春,病株下部和中部叶片上生有
Garlic is an important vegetable, mostly autumn planting, from the emergence to the growing stage of the occurrence of more types of diseases, especially in the continuous cropping diseases occur heavy, now the symptoms of several major pests and prevention methods are described below: Leaf blight. The disease is a fungal disease that can harm garlic leaves, mulberry leaves and other parts of the sheath, the occurrence of a wide area, endangering, causing garlic early dry, garlic vine rot, the epidemic of the year caused by 50% to 80% reduction. Symptoms can be divided into five types: First, sharp-witted type. Occurred in the wintering and early spring, diseased leaves into brown or dark brown, necrotic curl. Humidity at the tip of the necrotic site grow black mildew layer, a few leaves with less obvious purple brown markings. Necrotic often expand to the middle of the leaves, resulting in severe yellowish brown. Second, the striped pattern. Occurred in wintering and early spring, diseased plants in the lower part and the middle of the leaves have