危害癥(zheng)狀：為害馬鈴薯(shu)的維(wei)管束組織，造成死(si)曲、死(si)株，甚(shen)至(zhi)引起(qi)爛窖(jiao)。受害植(zhi)株生長(chang)遲緩，節間縮(suo)短(duan)，瘦弱，分(fen)(fen)枝減(jian)少，葉片(pian)(pian)變(bian)小(xiao)；受害較晚的植(zhi)，癥(zheng)狀不明顯，僅(jin)頂部(bu)(bu)葉片(pian)(pian)變(bian)小(xiao)，不表(biao)現(xian)(xian)萎(wei)蔫(nian)。病株萎(wei)蔫(nian)癥(zheng)狀一般在(zai)生長(chang)后期(qi)才(cai)顯著，自(zi)下而(er)上發展(zhan)，首先下部(bu)(bu)葉片(pian)(pian)萎(wei)蔫(nian)下垂而(er)枯死(si)。部(bu)(bu)葉片(pian)(pian)沿中脈(mo)向內(nei)卷(juan)曲，失水萎(wei)蔫(nian)．葉色(se)灰(hui)綠(lv)，植(zhi)株早枯，葉片(pian)(pian)不脫落；如切斷莖稈，用手(shou)擠壓。可見有乳白色(se)粘性(xing)的細(xi)菌(jun)(jun)自(zi)維(wei)管束溢(yi)出。病薯(shu)塊經過貯(zhu)藏后，薯(shu)皮(pi)變(bian)為褐色(se)，病株薯(shu)尾(臍)部(bu)(bu)皺(zhou)縮(suo)凹(ao)陷(xian)，剖視內(nei)部(bu)(bu)，維(wei)管束環變(bian)黃褐色(se)，環腐部(bu)(bu)分(fen)(fen)也有黃色(se)菌(jun)(jun)膿(nong)溢(yi)出。薯(shu)塊皮(pi)層與髓部(bu)(bu)易分(fen)(fen)離，外部(bu)(bu)表(biao)皮(pi)常出現(xian)(xian)龜裂，常致(zhi)軟(ruan)腐病菌(jun)(jun)二次侵染，使(shi)薯(shu)塊迅速腐爛。

防治方法：

1.選(xuan)(xuan)留無(wu)病種(zhong)薯：可采(cai)(cai)用(yong)秋播留種(zhong)的辦法(fa)，選(xuan)(xuan)出(chu)適中的小型塊莖作種(zhong)用(yong)。北方(fang)產區應有(you)計(ji)劃地建立(li)無(wu)病留種(zhong)田，采(cai)(cai)用(yong)整薯播種(zhong)，生育(yu)期(qi)間隨時拔除病株，保(bao)證收獲無(wu)病種(zhong)薯。留種(zhong)田先收，在收、選(xuan)(xuan)、晾和入窖過程(cheng)中，嚴格進行挑選(xuan)(xuan)，剔除病薯，去(qu)雜去(qu)劣。 

2.播(bo)種(zhong)(zhong)(zhong)(zhong)前種(zhong)(zhong)(zhong)(zhong)薯(shu)(shu)處理：①種(zhong)(zhong)(zhong)(zhong)薯(shu)(shu)出窖后進行(xing)晾種(zhong)(zhong)(zhong)(zhong)或(huo)催芽(ya)，剔除(chu)病薯(shu)(shu)．選用(yong)(yong)健薯(shu)(shu)；②進行(xing)整薯(shu)(shu)播(bo)種(zhong)(zhong)(zhong)(zhong)，如需(xu)切(qie)(qie)塊(kuai)，切(qie)(qie)刀必須進行(xing)嚴格消(xiao)毒(du)，可用(yong)(yong)0.2％升(sheng)汞(gong)水、或(huo)0．1％高錳(meng)酸鉀液等浸(jin)漬．做到切(qie)(qie)一塊(kuai)消(xiao)毒(du)1次；③藥劑處理種(zhong)(zhong)(zhong)(zhong)薯(shu)(shu) 用(yong)(yong)50％托布津可濕性粉劑500倍液或(huo)1000倍的(de)升(sheng)汞(gong)水溶液浸(jin)泡種(zhong)(zhong)(zhong)(zhong)薯(shu)(shu)2小時，然(ran)后晾千(qian)播(bo)種(zhong)(zhong)(zhong)(zhong)。還可選用(yong)(yong)種(zhong)(zhong)(zhong)(zhong)薯(shu)(shu)重量的(de)0．1-O．2％的(de)敵克(ke)松(song)加(jia)草木灰拌(ban)種(zhong)(zhong)(zhong)(zhong)，均有良好防效。 

3.及時拔除銷(xiao)毀病株，以(yi)減少病源 

4.安全貯(zhu)藏 種(zhong)薯經過精選、單藏等工作。 

以(yi)上是土(tu)豆(dou)環腐病防治(zhi)方法，為了避免農作物(wu)的(de)(de)減產，把土(tu)豆(dou)環腐病防治(zhi)方法送給大(da)家(jia)，希望大(da)家(jia)的(de)(de)土(tu)豆(dou)產量都有所提高，獲得更(geng)多(duo)的(de)(de)經濟效益。如(ru)果還(huan)想(xiang)了解更(geng)多(duo)，可以(yi)到農業之(zhi)友--土(tu)豆(dou)頻道，查看更(geng)多(duo)關于土(tu)豆(dou)的(de)(de)信息。