7月17-18日，全國農技中心在黑龍江省哈爾濱市召開了全國棉花病蟲害發生趨勢會商會。棉花生產(chan)省(sheng)（區、市(shi)）的(de)測報(bao)技術人員(yuan)和(he)(he)相關專家，根據目(mu)前棉花病蟲害發生(sheng)情況(kuang)、品種布局和(he)(he)種植方式，結合(he)氣(qi)候趨(qu)勢預測等因(yin)素綜(zong)合(he)分(fen)析(xi)，預計今年棉花中(zhong)(zhong)后期(qi)主要病蟲害總體為中(zhong)(zhong)等發生(sheng)，三(san)代棉鈴蟲、棉盲蝽、棉葉螨(man)、伏蚜和(he)(he)鈴病在新疆和(he)(he)黃河流(liu)域(yu)局部棉區可達偏(pian)重程度發生(sheng)。

      一、前期發生概況

      全(quan)國棉(mian)(mian)(mian)花前(qian)期(qi)(qi)(qi)病(bing)(bing)蟲害總體偏輕(qing)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)，發(fa)(fa)(fa)生(sheng)(sheng)(sheng)程度輕(qing)于上年，其中(zhong)，苗(miao)(miao)期(qi)(qi)(qi)蚜蟲在(zai)新疆和山(shan)東局部棉(mian)(mian)(mian)區(qu)偏重發(fa)(fa)(fa)生(sheng)(sheng)(sheng)，河(he)北(bei)(bei)、山(shan)西(xi)、湖(hu)(hu)北(bei)(bei)為(wei)中(zhong)等(deng)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)；二(er)(er)代(dai)棉(mian)(mian)(mian)盲蝽在(zai)新疆、河(he)北(bei)(bei)，棉(mian)(mian)(mian)葉螨在(zai)湖(hu)(hu)南(nan)、湖(hu)(hu)北(bei)(bei)，苗(miao)(miao)病(bing)(bing)在(zai)河(he)北(bei)(bei)、江(jiang)西(xi)，黃萎(wei)病(bing)(bing)在(zai)湖(hu)(hu)北(bei)(bei)、江(jiang)西(xi)和新疆局部棉(mian)(mian)(mian)區(qu)為(wei)中(zhong)等(deng)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)；二(er)(er)代(dai)棉(mian)(mian)(mian)鈴蟲雖在(zai)山(shan)東、河(he)北(bei)(bei)等(deng)地卵量(liang)較高，但各棉(mian)(mian)(mian)區(qu)幼(you)蟲量(liang)普遍(bian)較低，未(wei)造成(cheng)明顯為(wei)害。前(qian)期(qi)(qi)(qi)棉(mian)(mian)(mian)花病(bing)(bing)蟲害發(fa)(fa)(fa)生(sheng)(sheng)(sheng)面積4922萬(wan)畝次，其中(zhong)，苗(miao)(miao)期(qi)(qi)(qi)蚜蟲、二(er)(er)代(dai)棉(mian)(mian)(mian)鈴蟲、棉(mian)(mian)(mian)盲蝽、棉(mian)(mian)(mian)葉螨、棉(mian)(mian)(mian)薊馬等(deng)蟲害累計(ji)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)3800萬(wan)畝次，苗(miao)(miao)病(bing)(bing)、枯萎(wei)病(bing)(bing)和黃萎(wei)病(bing)(bing)等(deng)病(bing)(bing)害累計(ji)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)1122萬(wan)畝次，主要棉(mian)(mian)(mian)區(qu)各病(bing)(bing)蟲發(fa)(fa)(fa)生(sheng)(sheng)(sheng)面積見表1。

表(biao)1   棉花前期主要病蟲害分(fen)棉區發(fa)生面積

       二、中后期發生預測

      （一）發(fa)生趨(qu)勢

      棉(mian)花中(zhong)(zhong)后期(qi)(qi)病(bing)蟲害(hai)總體為中(zhong)(zhong)等程度發(fa)生(sheng)(sheng)，發(fa)生(sheng)(sheng)為害(hai)重于前(qian)期(qi)(qi)，其中(zhong)(zhong)，三代(dai)棉(mian)鈴蟲在新疆北疆局部、棉(mian)花鈴病(bing)和(he)棉(mian)盲蝽在黃河流域棉(mian)區、棉(mian)葉螨和(he)伏蚜在新疆北疆可(ke)達(da)偏重程度發(fa)生(sheng)(sheng)。預計中(zhong)(zhong)后期(qi)(qi)病(bing)蟲害(hai)發(fa)生(sheng)(sheng)面(mian)積為8500萬畝次，其中(zhong)(zhong)蟲害(hai)發(fa)生(sheng)(sheng)6500萬畝次，病(bing)害(hai)發(fa)生(sheng)(sheng)2000萬畝次，各病(bing)蟲預測發(fa)生(sheng)(sheng)面(mian)積和(he)發(fa)生(sheng)(sheng)盛(sheng)期(qi)(qi)見表2。

表2   棉花中(zhong)后期(qi)期(qi)主(zhu)要(yao)病蟲害(hai)預測(ce)發生面(mian)積和(he)發生盛期(qi)

      （二）預(yu)報依據

   ;   1. 棉鈴蟲和(he)棉盲蝽等(deng)蟲源(yuan)基數多偏低，病害菌源(yuan)較(jiao)為普遍

      7月上(shang)旬各(ge)棉(mian)(mian)區(qu)(qu)調(diao)查病(bing)蟲基數，主要(yao)害蟲基數多(duo)低(di)于常年(nian)(nian)和(he)上(shang)年(nian)(nian)。其(qi)中，二(er)代棉(mian)(mian)鈴蟲在(zai)山東(dong)和(he)河北等(deng)(deng)主要(yao)發生區(qu)(qu)平均畝殘蟲量(liang)(liang)約為(wei)30頭(tou)，低(di)于常年(nian)(nian)約30%，但(dan)山東(dong)惠民達468頭(tou)，高于常年(nian)(nian)均值(zhi)5%；二(er)代棉(mian)(mian)盲蝽各(ge)棉(mian)(mian)區(qu)(qu)百(bai)(bai)株(zhu)蟲量(liang)(liang)多(duo)低(di)于5頭(tou)，低(di)于常年(nian)(nian)約20%，新(xin)疆阿克蘇、山西鹽湖(hu)(hu)等(deng)(deng)地百(bai)(bai)株(zhu)蟲量(liang)(liang)10頭(tou)以上(shang)，比(bi)(bi)常年(nian)(nian)增加1.5倍；苗蚜各(ge)棉(mian)(mian)區(qu)(qu)蚜量(liang)(liang)多(duo)在(zai)百(bai)(bai)株(zhu)百(bai)(bai)頭(tou)以下，但(dan)山東(dong)濰坊、新(xin)疆建設(she)兵團農(nong)二(er)師29團、山西鹽湖(hu)(hu)區(qu)(qu)、新(xin)疆瑪納(na)斯平均百(bai)(bai)株(zhu)蚜量(liang)(liang)分(fen)別達5800頭(tou)、6200頭(tou)、2200頭(tou)和(he)1200頭(tou)，比(bi)(bi)常年(nian)(nian)偏高10%以上(shang)；蕾期葉螨多(duo)在(zai)百(bai)(bai)株(zhu)30頭(tou)以下，湖(hu)(hu)北新(xin)洲、新(xin)疆尉犁(li)、湖(hu)(hu)北鐘(zhong)祥(xiang)、湖(hu)(hu)南漢壽百(bai)(bai)株(zhu)螨量(liang)(liang)分(fen)別為(wei)1247頭(tou)、417頭(tou)、220頭(tou)、153頭(tou)，比(bi)(bi)常年(nian)(nian)增加5%以上(shang)。各(ge)棉(mian)(mian)區(qu)(qu)棉(mian)(mian)花多(duo)為(wei)連作種植，導致棉(mian)(mian)田(tian)黃萎病(bing)和(he)鈴病(bing)等(deng)(deng)病(bing)菌分(fen)布廣(guang)泛、菌源(yuan)充足。

      2．種(zhong)植制度對病蟲害發(fa)生為害有利

      今年(nian)全(quan)國棉(mian)(mian)花種(zhong)植(zhi)面(mian)積約5000萬畝(mu)，黃河和(he)(he)(he)長(chang)(chang)江流域(yu)棉(mian)(mian)區(qu)種(zhong)植(zhi)面(mian)積約占27%，新疆(jiang)棉(mian)(mian)區(qu)超(chao)過(guo)7成。各(ge)(ge)棉(mian)(mian)區(qu)Bt棉(mian)(mian)種(zhong)植(zhi)面(mian)積比率大(da)，中后期抗(kang)性比前期有所(suo)下降，將利(li)于三、四代棉(mian)(mian)鈴(ling)蟲幼蟲發生為害。黃河流域(yu)、長(chang)(chang)江流域(yu)棉(mian)(mian)區(qu)及新疆(jiang)部(bu)分棉(mian)(mian)區(qu)分散種(zhong)植(zhi)區(qu)域(yu)，采用棉(mian)(mian)花與(yu)蔬菜和(he)(he)(he)果樹鄰作、間(jian)作，有利(li)于棉(mian)(mian)盲蝽、棉(mian)(mian)鈴(ling)蟲、棉(mian)(mian)葉螨和(he)(he)(he)煙粉(fen)虱(shi)等多種(zhong)害蟲在各(ge)(ge)作物田(tian)(tian)輾(zhan)轉(zhuan)為害。各(ge)(ge)棉(mian)(mian)區(qu)主栽品(pin)種(zhong)對黃萎病和(he)(he)(he)鈴(ling)病抗(kang)性普遍(bian)較(jiao)差，有利(li)于此類病害的發生，且新疆(jiang)地膜覆蓋和(he)(he)(he)滴灌田(tian)(tian)面(mian)積較(jiao)大(da)，將有利(li)于中后期黃萎病病情發展。

      3．氣象條件(jian)對(dui)黃(huang)河流域(yu)和新疆棉區(qu)主要病(bing)蟲(chong)發生有利(li)

      據(ju)國家氣候中心預測，夏(xia)季，黃(huang)(huang)河流(liu)域(yu)和(he)新(xin)疆(jiang)棉(mian)區(qu)氣溫(wen)偏(pian)(pian)(pian)(pian)(pian)高(gao)0.5-1℃；黃(huang)(huang)河流(liu)域(yu)降水(shui)偏(pian)(pian)(pian)(pian)(pian)多2-5成，對(dui)棉(mian)盲蝽和(he)病害(hai)發生(sheng)有利；新(xin)疆(jiang)棉(mian)區(qu)降水(shui)接(jie)近常年，有利于棉(mian)鈴蟲、棉(mian)蚜(ya)和(he)棉(mian)葉螨等害(hai)蟲發生(sheng)。長江(jiang)流(liu)域(yu)棉(mian)區(qu)氣溫(wen)偏(pian)(pian)(pian)(pian)(pian)高(gao)1-2℃，降水(shui)偏(pian)(pian)(pian)(pian)(pian)少2-5成，對(dui)多數病蟲害(hai)發生(sheng)有一定抑制作用(yong)。今年登陸我國臺風偏(pian)(pian)(pian)(pian)(pian)多、偏(pian)(pian)(pian)(pian)(pian)強，如(ru)臺風登陸位(wei)置偏(pian)(pian)(pian)(pian)(pian)北，引起棉(mian)區(qu)多雨和(he)氣溫(wen)降至25℃以下，會導致黃(huang)(huang)萎病在沿海及沿江(jiang)棉(mian)區(qu)暴發。

    （病蟲害測報處供稿）