西瓜蔓割病的发生与防治内容摘要:
2、右,不向上和向下蔓延,这一点是和蔓枯病的主要区别。 病部绕茎一周并缢缩,干后病斑仍呈红灰白色,但一般死亡率低。 2 病原及发生规律根据我们 3 年来的试验研究和南京农业大学植物病原菌研究室的鉴定为西瓜蔓割病。 其病原菌有性世代为瓜类球腔菌,属球腔菌属。 无性时代为黄瓜壳二孢,属壳二孢属。 病菌以分生孢子器及子囊腔在病组织上或土壤中越冬。 翌年 12月条件适宜时,萌发侵入寄主为害。 所以西瓜温室育苗,加之温度高,湿度大,该病发生早为害重。 大棚和小拱棚内移栽的西瓜,一般 3 月间发生。 病菌在温度 815时,湿度大,病害就可发生。 最适温度为 27左右。 病菌的传染途径主要是靠人为和重茬育苗、重茬种植传播为害。 这与书上介绍的瓜类枯萎病所称的蔓割病是不同的,它的病原菌是尖孢镰刀菌,主要为害根部。 3 业防治注意轮作,不可重温室育苗、重棚移栽西瓜。 剂防治在发病初期,除经常放风、通气,降低棚内温度湿度外,要及时用药防治。 3年来防治试验结果证明:用 50%力克菌、25%瑞毒霉、70%甲基托布津、75%百菌清、50%扑海因、10%多氧霉素、70%代森锰锌、博、10%世高等任何一种农药拌成糊状,涂抹在病部,其防治效果均可达 90%以上,持效期为 1015 天。 但用喷雾法防治效果差。 涂抹法具体用法是:涂抹前,先把病斑弄破,再涂抹药液。 专利查询。西瓜蔓割病的发生与防治
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