紅(hong)苕(tiao)枯(ku)萎(wei)病(bing),苗(miao)期(qi)和(he)長(chang)薯(shu)塊(kuai)期(qi)間(jian)都(dou)會(hui)感(gan)染(ran),苗(miao)期(qi)染(ran)病(bing)主(zhu)要(yao)是(shi)莖(jing)基(ji)部(bu),葉(ye)片(pian)先(xian)變(bian)黃(huang),莖(jing)基(ji)部(bu)膨(peng)大(da)縱(zong)向(xiang)開(kai)裂(lie),露(lu)出(chu)髓(sui)部(bu),橫(heng)剖(pou)可(ke)見(jian)維(wei)管(guan)束(shu)變(bian)為(wei)黑(hei)褐(he)色(se),裂(lie)開(kai)處(chu)呈(cheng)纖(xian)維(wei)狀(zhuang)。薯塊染病薯蒂部呈腐爛狀。病株葉片向上逐漸變黃後脫落,最後全蔓幹枯而死,這種紅苕萎縮病嚴重時可造成紅苕減產30%到70%,shihongtiaozhuyaobinghaizhiyi。yinciweiyuanxiannongyejudenongyishiyaopingtetixingnongminpengyouyidingbuyaohushihongtiaoweisuobingdefangzhi。tashuo,yaoyouxiaofangzhihongtiaoweisuobingshouxianyingzhangwotadefabingtezheng,zhezhonghongtiaoweisuobingcunhuoqihenchang,zaiturangzhongkeda3年,病薯病苗遠近距離都能傳播,多以流水、農具浸入。雨水多利於流行,連作地、沙地或沙壤土發病機率更大。
根據這些特點和特征,應當選用抗病強的品種作種苕,絕不能栽植有病害的紅苕或苕苗,一般不要從外地購買種苕種苗;zaizhifangshizuihaocaiyongshuangxingyuliu,yixingzhongyumi,yixingzaihongtiao,lainiantiaohuan,bazaiguohongtiaodeyixingzhongyumi,zhongguoyumideyixingyonglaizaihongtiao,zheyangmeiniantiaohuankedadajianshaoranbinglv。yekeyong70%甲基硫菌靈可濕性粉劑700倍液浸種、浸苗,一經發病,要及早噴灑70%甲基硫菌靈可濕性粉劑800倍液,或者用50%苯菌靈可濕性粉劑1500倍液噴灑,必要時也可用上屬藥液灌窩。
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