癥狀 主要為(wei)害葉(xie)片(pian)和(he)莖。葉(xie)片(pian)染病(bing)(bing)(bing)病(bing)(bing)(bing)斑(ban)圓形至橢圓形，中間灰(hui)白色(se)(se)至暗灰(hui)色(se)(se)，邊緣(yuan)深褐色(se)(se)，病(bing)(bing)(bing)、健部(bu)界(jie)限明顯，后(hou)期病(bing)(bing)(bing)部(bu)兩面生出(chu)小黑點，即病(bing)(bing)(bing)菌的分生孢子盤；莖部(bu)染病(bing)(bing)(bing)初生梭狀不規則(ze)斑(ban)，中間灰(hui)白色(se)(se)、四周(zhou)黑色(se)(se)，嚴(yan)重的上、下病(bing)(bing)(bing)斑(ban)融合(he)成片(pian)，致(zhi)全(quan)株變黑而干枯，病(bing)(bing)(bing)部(bu)長滿黑色(se)(se)小粒點。 

病原 G10merlla cingulata （Stonem.） Spauid.et Schreck 稱(cheng)圍小(xiao)(xiao)叢殼(ke)，屬(shu)子(zi)(zi)囊(nang)菌亞門(men)真菌。無(wu)性態為Colletotrichum g10eosporioides （Ces.）Wil3稱(cheng)膠孢(bao)(bao)炭疽菌，屬(shu)半知菌亞門(men)真菌。圍小(xiao)(xiao)叢殼(ke)在PDA培養基(ji)(ji)上(shang)產(chan)生(sheng)(sheng)(sheng)子(zi)(zi)囊(nang)殼(ke)，集生(sheng)(sheng)(sheng)，近球形(xing)(xing)(xing)(xing)，大(da)小(xiao)(xiao)104一(yi)168μm，殼(ke)高9l―155μm；子(zi)(zi)囊(nang)棍棒(bang)(bang)狀(zhuang)(zhuang)，單層壁，大(da)小(xiao)(xiao)47―62×10一(yi)14（μm）；子(zi)(zi)囊(nang)孢(bao)(bao)子(zi)(zi)單胞(bao)(bao)(bao)無(wu)色(se)(se)(se)，橢(tuo)(tuo)(tuo)(tuo)圓(yuan)(yuan)(yuan)形(xing)(xing)(xing)(xing)至(zhi)長卵形(xing)(xing)(xing)(xing)，略(lve)彎曲(qu)，大(da)小(xiao)(xiao)13―19×4―6（μm）；無(wu)性態分(fen)(fen)生(sheng)(sheng)(sheng)孢(bao)(bao)子(zi)(zi)盤(pan)表生(sheng)(sheng)(sheng)，稀(xi)疏，圓(yuan)(yuan)(yuan)形(xing)(xing)(xing)(xing)至(zhi)橢(tuo)(tuo)(tuo)(tuo)圓(yuan)(yuan)(yuan)形(xing)(xing)(xing)(xing)，黑(hei)(hei)褐色(se)(se)(se)，盤(pan)周緣著(zhu)生(sheng)(sheng)(sheng)有(you)剛(gang)毛，黑(hei)(hei)褐色(se)(se)(se)，基(ji)(ji)部(bu)稍膨大(da)，頂(ding)(ding)端尖(jian)銳，高35―79μm；分(fen)(fen)生(sheng)(sheng)(sheng)孢(bao)(bao)子(zi)(zi)梗無(wu)，產(chan)孢(bao)(bao)細胞(bao)(bao)(bao)短，瓶梗狀(zhuang)(zhuang)，無(wu)色(se)(se)(se)，平行(xing)排列；分(fen)(fen)生(sheng)(sheng)(sheng)孢(bao)(bao)子(zi)(zi)圓(yuan)(yuan)(yuan)筒形(xing)(xing)(xing)(xing)，單胞(bao)(bao)(bao)無(wu)色(se)(se)(se)，內生(sheng)(sheng)(sheng)1一(yi)2個油球，大(da)小(xiao)(xiao)10一(yi)15×3―5（μm）；附著(zhu)胞(bao)(bao)(bao)不規(gui)則形(xing)(xing)(xing)(xing)至(zhi)棍棒(bang)(bang)狀(zhuang)(zhuang)，四周不規(gui)則，致病(bing)力(li)強(qiang)。此(ci)外(wai)Colletotrichum capsici （Syd.）Butler etBisby稱(cheng)辣椒刺(ci)盤(pan)孢(bao)(bao)，C.capici 分(fen)(fen)生(sheng)(sheng)(sheng)孢(bao)(bao)子(zi)(zi)盤(pan)表生(sheng)(sheng)(sheng)，稀(xi)疏，圓(yuan)(yuan)(yuan)形(xing)(xing)(xing)(xing)或橢(tuo)(tuo)(tuo)(tuo)圓(yuan)(yuan)(yuan)形(xing)(xing)(xing)(xing)，黑(hei)(hei)色(se)(se)(se)，大(da)小(xiao)(xiao)55―167μm，剛(gang)毛密集；分(fen)(fen)生(sheng)(sheng)(sheng)孢(bao)(bao)子(zi)(zi)梗分(fen)(fen)枝；產(chan)孢(bao)(bao)細胞(bao)(bao)(bao)圓(yuan)(yuan)(yuan)筒形(xing)(xing)(xing)(xing)；分(fen)(fen)生(sheng)(sheng)(sheng)孢(bao)(bao)子(zi)(zi)單胞(bao)(bao)(bao)無(wu)色(se)(se)(se)，鐮刀形(xing)(xing)(xing)(xing)，基(ji)(ji)部(bu)鈍(dun)圓(yuan)(yuan)(yuan)，頂(ding)(ding)部(bu)尖(jian)，大(da)小(xiao)(xiao)17―26×3.3（μm），附著(zhu)胞(bao)(bao)(bao)橢(tuo)(tuo)(tuo)(tuo)圓(yuan)(yuan)(yuan)形(xing)(xing)(xing)(xing)至(zhi)棍棒(bang)(bang)狀(zhuang)(zhuang)，暗褐色(se)(se)(se)，邊緣較規(gui)則。它經常和膠孢(bao)(bao)炭疽菌一(yi)起發(fa)生(sheng)(sheng)(sheng)，終年為害，3―8月受害重(zhong)。此(ci)外(wai)，有(you)認為C.pestis Massee也是該病(bing)病(bing)原。 

傳播途徑和發病條件 以菌(jun)絲體和分生(sheng)孢(bao)子(zi)盤在病部或(huo)隨病殘體遺落土(tu)中越冬。翌年6月(yue)產生(sheng)大量分生(sheng)孢(bao)子(zi)借風雨傳播，進(jin)行初侵(qin)染(ran)(ran)和多次再侵(qin)染(ran)(ran)，不斷擴大蔓延，一直延續(xu)到收獲。氣(qi)溫25―30℃，相對濕(shi)度80%易發(fa)病。天氣(qi)溫暖多濕(shi)或(huo)霧大露重(zhong)(zhong)有利發(fa)病，偏施過施氮(dan)或(huo)植地郁(yu)蔽(bi)、通風透光不良會(hui)使病害加重(zhong)(zhong)。 

防治方法 （1）選用早白薯(shu)、鶴(he)頸薯(shu)、黎(li)洞薯(shu)、紅肉薯(shu)等耐澇(lao)品種(zhong)，可減(jian)輕發(fa)病。（2）常發(fa)地或重病地避免連作，注意加(jia)(jia)強水肥(fei)(fei)管理。施用酵(jiao)素菌(jun)(jun)漚制的(de)堆肥(fei)(fei)或腐熟的(de)有機肥(fei)(fei)，采用配方施肥(fei)(fei)技術，適(shi)當增施磷鉀肥(fei)(fei)，避免偏施過施氮肥(fei)(fei)，做(zuo)到(dao)高畦深溝(gou)，清污(wu)排(pai)漬，改善植(zhi)地通(tong)透性(xing)。（3）發(fa)病初期開始噴灑30%氧氯化(hua)銅(tong)懸浮(fu)劑(ji)(ji)(ji)600倍(bei)(bei)液(ye)加(jia)(jia)70%甲(jia)基(ji)硫菌(jun)(jun)靈(ling)可濕(shi)性(xing)粉(fen)劑(ji)(ji)(ji)800倍(bei)(bei)液(ye)或70%甲(jia)基(ji)硫菌(jun)(jun)靈(ling)可濕(shi)性(xing)粉(fen)劑(ji)(ji)(ji)1000倍(bei)(bei)液(ye)加(jia)(jia)75%百菌(jun)(jun)清可濕(shi)性(xing)粉(fen)劑(ji)(ji)(ji)1000倍(bei)(bei)液(ye)、50%復方硫菌(jun)(jun)靈(ling)可濕(shi)性(xing)粉(fen)劑(ji)(ji)(ji)1000倍(bei)(bei)液(ye)、40%多(duo)?硫懸浮(fu)劑(ji)(ji)(ji)（滅病威）500倍(bei)(bei)液(ye)、50%苯(ben)菌(jun)(jun)靈(ling)可濕(shi)性(xing)粉(fen)劑(ji)(ji)(ji)1500倍(bei)(bei)液(ye)、60%防(fang)霉(mei)寶超(chao)微(wei)可濕(shi)性(xing)粉(fen)劑(ji)(ji)(ji)800倍(bei)(bei)液(ye)，隔(ge)10一(yi)15天(tian)1次(ci)，連續防(fang)治2―3次(ci)。