幼you苗miao發fa病bing,開kai始shi莖jing基ji部bu出chu現xian水shui漬zi狀zhuang腐fu爛lan,病bing部bu暗an綠lv色se,最zui後hou猝cu倒dao或huo立li枯ku狀zhuang死si去qu。成cheng株zhu期qi葉ye片pian發fa病bing,開kai始shi葉ye片pian呈cheng暗an綠lv色se圓yuan形xing病bing斑ban,邊bian緣yuan不bu明ming顯xian,空kong氣qi潮chao濕shi時shi病bing斑ban迅xun速su擴kuo大da,使shi整zheng個ge葉ye片pian軟ruan腐fu。空氣幹燥時,病斑停止擴展,邊緣漸漸明晰。莖和枝條發病,開始產生暗褐色和黑色條斑,邊緣不明顯。莖基部發病,出現暗褐色和黑色軟腐、huaisi,youtubiaoxiaxiangtubiaoshangfazhan,yinqizhizhuweiyan,zuihousiwang。guoshifabing,duocongguodibukaishi,xingchenganlvseshuizizhuangbuguizexingbingban,kaishibianyuanbumingxian,yihouhenkuaibianjiquanguo,yansejiazhong,chenganlvzhianhese,shenzhiguorouhezhongziyebianchenghese,chaoshishiguomianshanghaichangchuxishudebaisexuzhuangmeiceng。
發病規律
gaibingshiyoulajiaoyimeijunqinrandeyizhongzhenjunbinghai。bingjunyiluanbaozihuohouyuanbaozizaiturangzhongdebingzhucantihuozhongzishangyuedong。bingyuantishangchanshengdebaozinang,jieqiliu、yushuiheguangaishuijinxingchuanbo,baozinangkeyizhijiemengfaqinran,yekeyishifangyoudongbaoziqinrujizhu,zhishibinghailiuxing。gaowengaoshiyouliyubinghaidefashengheliuxing。bingjunzai10~37℃均可生長發育,氣溫在25~30℃,相對濕度在85%以上,往往發病最重。連續陰雨天,田間積水,地麵潮濕,重茬,大水漫灌,都會加重病情發展。
防治方法
1.農業防治。選用抗病品種,如羊角椒、細線椒等。實行與茄果類蔬菜2~3年以上的輪作,前茬以糧田、十字花科和豆科茬為好。育苗地要用未種過辣椒的新土,苗床要施足腐熟的有機肥,移栽時苗齡要在80天左右,株高15~20厘米,80%現蕾的大苗,移栽時最好用永業生命素泥漿蘸根,可縮短緩苗期。定植密度要適當,每畝4000~4500株。特別是雨後要注意及時排水除濕,中耕鬆土,及時清除病株殘果,減少傳染源。
2.藥劑防治。播前可用20%甲基立枯磷乳油1000倍液浸種12小時,晾幹後催芽播種。辣椒生長期間,噴藥可用58%甲霜靈·錳鋅可濕性粉劑500倍液,或64%殺毒礬可濕性粉劑500倍液,或70%乙磷·錳鋅可濕性粉劑500倍液,或80%三乙磷酸鋁(乙磷鋁、疫霜靈)600倍液,每7~10天噴1次,連續噴3~4次。為降低病害的抗藥性,以上幾種農藥可交替使用。
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