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甜瓜苗在生长期有可能感染多种疾病,但最普遍的就是枯萎病。枯萎病从幼苗到瓜采收期均可发生,但结瓜期是为严重。病害发生在蔓部,严重时可产生油状分泌物,最终导致甜瓜病株叶片由上而下逐渐枯萎。枯萎病是由一种枯萎病菌引起的,枯萎病菌以菌丝体、厚垣孢子和菌核病株残体在土壤中和种子上越冬,病菌生活力特别强,能残存5年以上,发病适宜温度是24—28℃,也就是甜瓜结瓜的最适温度。另外土壤偏酸、温度变化剧烈和氮肥过多都有利于发病。一般病菌从根毛顶
Melon seedlings in the growing season may be infected with a variety of diseases, but the most common is the blight. Fusarium wilt from seedling to melon harvest can occur, but the fruiting period is serious. Diseases occur in the vine, severe cases can produce oily secretions, eventually leading to melon diseased leaves gradually wilt from top to bottom. Fusarium wilt is caused by a kind of Fusarium oxysporum, Fusarium oxysporum f. Mycelia, Chlamydomonas and Sclerotinia persimmon winter in the soil and seeds, the viability of the bacteria is particularly strong, can survive for more than 5 years, the incidence is appropriate The temperature is 24-28 ℃, that is, the optimum temperature melon fruiting. In addition the soil partial acid, dramatic temperature changes and excessive nitrogen are conducive to the incidence. General germs from the root hair top