jichangyuhouqiwenxiajiang,turangshiduzengda,dangqianmiantianjiaopubiandifashenglehuangweibing,erqieyoujiakuaimanyanhejiazhongfazhanzhishi。zhengzhuangbiaoxianduoyanghua,haiyoudehekuweibinghunfa,hennanqufenkai。 現在多數棉田發病程度還不太嚴重,病葉出現在中下部和少數棉株;但少數地塊病情嚴重,有的甚至葉片和花蕾開始脫落或突然萎蔫死亡。這樣的地塊大多為多年連作又不施有機肥、瘠薄缺肥地、嚴重缺鉀地、低窪粘濕地、整地粗放或除草劑為害致使根係發育不良、中下部結鈴多沒有及時補充營養的地塊。症狀出現在8 月份,但根源卻是前中期管理不當造成的。
muqianhaimeiyouduihuangweibingmianyidemianhuapinzhong,zhishikangnaichengdubutong。suizhemianzhudejinyibushuailao,zuizhongmianhuahuangweibingdefabingzhulvjihudoushibaifenzhibai,danzhiyaoshifabingjiaowanerqiejuxianzaixiabuyepian,duimianhuachanliangbuhuizaochengshenmeyingxiang。dangqiankangnaihuangweibingdepinzhongbushao,zhiyaocaiquzonghecuoshibaochimianzhutizhijianzhuang,duimianhuahuangweibingshibunankongzhide。zhexiecuoshibaokuo:保持較深的耕作層、安全使用除草劑、施足底肥,使根係健壯發育;增施有機肥,增加土壤中的有益菌以削弱病菌;增施鉀肥,增強棉株抗病能力;花鈴盛期滿足水肥供應,不使棉株超負荷結鈴等。
縱觀幾個棉花黃枯萎病的易發病期,都是由“內虛外感”兩方麵的因素引發的。第一段:出苗後,子葉中貯存的養分已用完,棉苗的根係尚未建成,一旦遇到低溫、地濕、土硬、除草劑危害、速效養分匱乏等,極易誘發病害;第二段:6 月中下旬,棉花由營養生長轉入營養生長和生殖生長並行,棉株即將開花,對養分的消耗突增,而發達的根係尚未建成,如遇多雨、低溫、地濕、幹旱、土壤板結、缺鉀等不利條件,又極易誘發病害;第三段:8月(yue)中(zhong)下(xia)旬(xun),此(ci)時(shi)中(zhong)下(xia)部(bu)已(yi)結(jie)鈴(ling),大(da)雨(yu)後(hou)土(tu)壤(rang)速(su)效(xiao)養(yang)分(fen)被(bei)淋(lin)溶(rong),棉(mian)株(zhu)已(yi)極(ji)度(du)虛(xu)弱(ruo),如(ru)養(yang)分(fen)供(gong)應(ying)一(yi)旦(dan)中(zhong)斷(duan),或(huo)養(yang)分(fen)不(bu)平(ping)衡(heng),又(you)會(hui)誘(you)發(fa)病(bing)害(hai)。所(suo)以(yi)當(dang)前(qian)控(kong)製(zhi)黃(huang)萎(wei)病(bing)的(de)著(zhe)重(zhong)點(dian)應(ying)是(shi)增(zeng)強(qiang)棉(mian)花(hua)體(ti)質(zhi)。
實踐證明:對發病輕的棉田和剛發病的棉田,或點片發病的棉田,噴施“ 魚蛋白有機葉麵肥”和“克黃枯”dounengqidaojiaohaodikongbingzuoyong,liangzhongzhijidouhanduozhongyingyangchengfen,quejiadizaijiapenjiaxiaoguogenghao,kezengqiangmianhuatizhi,tigaomianzhukangbingnaibingnengli,yanhuanbinghaidefazhan。huangweibingzhengzhuangbiaoxianzaiyepian,shouhaizuizhongdezeshijingganneibu,pensashajunjihezhuchangjizehennanzouxiao。
penshizhijizhuyaozheyanyubaohuweifabingdeyepianhemianzhu,kongzhigangfabingdeyepianhemianzhu,yanhuanqifabinghekuodabingqing。zhiyuduibingrugaohuangdemianzhuyaoqiupenyaohouqisihuisheng,huozhebingyepenyaohouwanhaoruchuzeshibukenengde。xianzailijicaiqucuoshihaibuwan,duiqingbingdihegangfabingdizhiyaocuoshidaowei,wanquankeyijianghuangweibingxianzhizaikekongfanweinei,buhuiduichanliangzaochengdadeyingxiang。
手機版




