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花生茎腐病,是花生重要病害之一。主要分布在我国北方花生产区,为害严重。近年来,由于认真推广了防治措施,发病率已压低到3%左右。一、病状(一)幼苗期:病原菌从开始萌动的种子的子叶或幼根侵入,最初使根颈部造成水浸状黄褐色病斑,后变黑褐色。病斑继续扩大,茎基部组织腐烂,上部叶片渐渐变黄色。当病斑扩展到绕茎一周时,整个植株萎蔫枯死。从开始发病到植株枯死,一般是4—5天。如果气候潮湿,病株枯死7天以后,病部逐渐出现黑色小突起,即病原菌的子实体。气候干燥时,病部表皮紧贴茎上,髓部干枯中空,不产生子实
Peanut stem rot is one of the important diseases of peanut. Mainly distributed in northern China flower production area, serious damage. In recent years, due to serious promotion of prevention and treatment measures, the incidence has been reduced to about 3%. First, the symptoms (a) seedling stage: Pathogen germination from the beginning of the seed cotyledons or young roots invade, the root cause of the root cause of the first blotchy tan spots, later dark brown. Lesions continue to expand, the base of the stem rot, the upper leaves gradually turn yellow. When the lesion spreads around the stem for a week, the entire plant wilted and wilted. From the onset of disease to dead plants, usually 4-5 days. If the weather is humid, the diseased plants die for seven days, the disease gradually appear small black protrusions, that is, the fruiting bodies of pathogens. When the climate is dry, the diseased part of the epidermis sticks to the stem tightly, and the medullary cavity dries out hollowly and does not produce fruiting bodies