5月9日(ri)-10日(ri),全國(guo)農技中心在廣(guang)東省廣(guang)州市召開了早稻(dao)主要病蟲害發(fa)(fa)生趨勢(shi)會商會,來(lai)自水稻(dao)主產省(區、市)的測報技術人(ren)員和(he)有關專家參加了會議。會議根據當(dang)前病蟲發(fa)(fa)生基數、近年發(fa)(fa)生趨勢(shi)、氣侯條(tiao)件和(he)水稻(dao)種植情況等因素(su)綜合分析,預計早稻(dao)病蟲害總體偏(pian)重發(fa)(fa)生,略輕于上年,發(fa)(fa)生面(mian)積(ji)約3億(yi)畝次(ci)。其中,蟲害以(yi)稻(dao)飛虱、稻(dao)縱卷葉螟和(he)二化螟為主,發(fa)(fa)生面(mian)積(ji)約2.14億(yi)畝次(ci);病害以(yi)稻(dao)瘟病和(he)稻(dao)紋枯病為主,發(fa)(fa)生面(mian)積(ji)約9400萬畝次(ci)。
一(yi)、發(fa)生趨勢
(一)水稻蟲害
稻(dao)(dao)飛虱(shi)在華南、江(jiang)南和(he)西南南部稻(dao)(dao)區(qu)偏(pian)重發(fa)(fa)(fa)生(sheng)(sheng),長(chang)江(jiang)中下游稻(dao)(dao)區(qu)中等(deng)(deng)(deng)發(fa)(fa)(fa)生(sheng)(sheng),全國發(fa)(fa)(fa)生(sheng)(sheng)面(mian)積(ji)8900萬畝(mu)(mu)次(ci);稻(dao)(dao)縱卷(juan)葉螟(ming)在華南、江(jiang)南和(he)長(chang)江(jiang)中游部分(fen)(fen)稻(dao)(dao)區(qu)中等(deng)(deng)(deng)發(fa)(fa)(fa)生(sheng)(sheng)、局(ju)部偏(pian)重發(fa)(fa)(fa)生(sheng)(sheng),全國發(fa)(fa)(fa)生(sheng)(sheng)面(mian)積(ji)7100萬畝(mu)(mu)次(ci);二化(hua)螟(ming)在江(jiang)南、長(chang)江(jiang)中游和(he)華南北部稻(dao)(dao)區(qu)偏(pian)重發(fa)(fa)(fa)生(sheng)(sheng)、局(ju)部大(da)發(fa)(fa)(fa)生(sheng)(sheng),全國發(fa)(fa)(fa)生(sheng)(sheng)面(mian)積(ji)4100萬畝(mu)(mu)次(ci);三化(hua)螟(ming)在華南部分(fen)(fen)稻(dao)(dao)區(qu)中等(deng)(deng)(deng)發(fa)(fa)(fa)生(sheng)(sheng),全國發(fa)(fa)(fa)生(sheng)(sheng)面(mian)積(ji)1300萬畝(mu)(mu)次(ci)。
(二)水稻病害(hai)
稻瘟病(bing)在(zai)華(hua)南(nan)、江南(nan)、西南(nan)南(nan)部稻區(qu)(qu)中(zhong)等流(liu)(liu)行,部分感病(bing)品種有偏(pian)(pian)重流(liu)(liu)行的可能,全國發(fa)病(bing)面(mian)積1600萬(wan)畝(mu);紋枯(ku)病(bing)在(zai)華(hua)南(nan)、江南(nan)和長(chang)江中(zhong)下(xia)游稻區(qu)(qu)偏(pian)(pian)重流(liu)(liu)行、局部大流(liu)(liu)行,全國發(fa)病(bing)面(mian)積7300萬(wan)畝(mu);南(nan)方(fang)水稻黑條矮縮(suo)病(bing)在(zai)華(hua)南(nan)、江南(nan)稻區(qu)(qu)發(fa)病(bing)面(mian)積大于500萬(wan)畝(mu),西南(nan)稻區(qu)(qu)見病(bing)范圍進(jin)一步擴大。
二、預測(ce)依據
(一(yi))境(jing)內外病蟲(chong)基數
據(ju)(ju)專(zhuan)家實(shi)地(di)調查,越南(nan)(nan)(nan)(nan)、老撾、緬甸等境(jing)外(wai)蟲(chong)(chong)(chong)(chong)源(yuan)地(di)水(shui)(shui)稻(dao)生(sheng)(sheng)(sheng)育(yu)期(qi)(qi)(qi)比常年(nian)推遲20-30天,當前大部(bu)水(shui)(shui)稻(dao)處(chu)于(yu)(yu)分蘗至孕穗(sui)期(qi)(qi)(qi),營養(yang)條件仍然適(shi)合“兩(liang)遷(qian)(qian)(qian)”害(hai)蟲(chong)(chong)(chong)(chong)取食(shi)危(wei)害(hai),這可能也是今年(nian)華南(nan)(nan)(nan)(nan)、西(xi)南(nan)(nan)(nan)(nan)南(nan)(nan)(nan)(nan)部(bu)稻(dao)區(qu)“兩(liang)遷(qian)(qian)(qian)”害(hai)蟲(chong)(chong)(chong)(chong)遷(qian)(qian)(qian)入(ru)(ru)時間(jian)偏(pian)晚、前期(qi)(qi)(qi)遷(qian)(qian)(qian)入(ru)(ru)蟲(chong)(chong)(chong)(chong)量(liang)(liang)偏(pian)少(shao)、田間(jian)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)相對(dui)較輕的原因之一。華南(nan)(nan)(nan)(nan)、西(xi)南(nan)(nan)(nan)(nan)病蟲(chong)(chong)(chong)(chong)監(jian)測點數(shu)(shu)據(ju)(ju)表明,大部(bu)稻(dao)區(qu)“兩(liang)遷(qian)(qian)(qian)”害(hai)蟲(chong)(chong)(chong)(chong)燈下(xia)始見期(qi)(qi)(qi)和(he)遷(qian)(qian)(qian)入(ru)(ru)高(gao)峰期(qi)(qi)(qi)比上(shang)年(nian)推遲5-10天;遷(qian)(qian)(qian)入(ru)(ru)峰次(ci)明顯偏(pian)少(shao),多(duo)數(shu)(shu)監(jian)測點出(chu)現(xian)1-4次(ci)遷(qian)(qian)(qian)入(ru)(ru)峰;遷(qian)(qian)(qian)入(ru)(ru)蟲(chong)(chong)(chong)(chong)量(liang)(liang)總體低(di)于(yu)(yu)上(shang)年(nian),但華南(nan)(nan)(nan)(nan)局部(bu)稻(dao)區(qu)出(chu)現(xian)畝(mu)蛾量(liang)(liang)1000頭以(yi)(yi)上(shang)稻(dao)縱卷葉螟(ming)遷(qian)(qian)(qian)入(ru)(ru)峰。田間(jian)蟲(chong)(chong)(chong)(chong)口(kou)密度低(di)于(yu)(yu)上(shang)年(nian),大部(bu)在(zai)中等發(fa)(fa)(fa)生(sheng)(sheng)(sheng)指標以(yi)(yi)下(xia)。雖然目(mu)前“兩(liang)遷(qian)(qian)(qian)”害(hai)蟲(chong)(chong)(chong)(chong)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)總體輕于(yu)(yu)上(shang)年(nian),但隨著境(jing)外(wai)蟲(chong)(chong)(chong)(chong)源(yuan)地(di)水(shui)(shui)稻(dao)逐(zhu)步成熟收割,大量(liang)(liang)蟲(chong)(chong)(chong)(chong)源(yuan)將遷(qian)(qian)(qian)入(ru)(ru)我國(guo),結合本地(di)蟲(chong)(chong)(chong)(chong)源(yuan)不斷繁殖,后(hou)期(qi)(qi)(qi)仍呈偏(pian)重發(fa)(fa)(fa)生(sheng)(sheng)(sheng)態勢。二化(hua)螟(ming)畝(mu)加權(quan)平均活蟲(chong)(chong)(chong)(chong)數(shu)(shu),湖南(nan)(nan)(nan)(nan)、江西(xi)、湖北為(wei)3000-4000頭,四川、重慶、安(an)徽為(wei)1000-2000頭,滿足(zu)偏(pian)重以(yi)(yi)上(shang)程度發(fa)(fa)(fa)生(sheng)(sheng)(sheng)的蟲(chong)(chong)(chong)(chong)源(yuan)基數(shu)(shu)條件。稻(dao)瘟病在(zai)華南(nan)(nan)(nan)(nan)和(he)西(xi)南(nan)(nan)(nan)(nan)南(nan)(nan)(nan)(nan)部(bu)早稻(dao)區(qu)局部(bu)已見病。
(二)水稻品種與(yu)栽(zai)插情況
今年我國(guo)早(zao)稻(dao)(dao)(dao)以粗稈大(da)穗、優質高產型為主栽品(pin)(pin)種的(de)格局沒有發(fa)生根本改變(bian)。這些(xie)品(pin)(pin)種生長量(liang)大(da)、田間(jian)郁閉,易形成適溫高濕的(de)田間(jian)小氣候(hou);大(da)部(bu)水稻(dao)(dao)(dao)品(pin)(pin)種抗病(bing)抗蟲性不(bu)高,有利于水稻(dao)(dao)(dao)病(bing)蟲害特別是稻(dao)(dao)(dao)飛(fei)虱、稻(dao)(dao)(dao)瘟(wen)病(bing)、紋枯病(bing)和南方水稻(dao)(dao)(dao)黑條(tiao)矮縮病(bing)的(de)發(fa)生與流(liu)行。另外,今年南方大(da)部(bu)稻(dao)(dao)(dao)區早(zao)稻(dao)(dao)(dao)栽插(cha)時間(jian)比去年略(lve)有推遲,目前云南南部(bu)早(zao)稻(dao)(dao)(dao)處(chu)于孕穗期,華南和江(jiang)南早(zao)稻(dao)(dao)(dao)處(chu)于返青至分蘗期,下階段寄主條(tiao)件(jian)將更加(jia)適宜(yi)病(bing)蟲發(fa)生和為害。
(三)氣象條件
據國家氣候中心預測,今(jin)年6月-8月除廣(guang)西大(da)部(bu)氣溫較常年同期偏低(di)、東(dong)北東(dong)部(bu)初夏可能出(chu)現階段(duan)性(xing)低(di)溫外,全國其(qi)余大(da)部(bu)地區的(de)(de)(de)氣溫接近常年同期或偏高(gao),有(you)利(li)于早(zao)稻(dao)病蟲(chong)發生;主(zhu)要多(duo)雨帶可能位于黃(huang)淮、江(jiang)(jiang)淮地區,淮河流(liu)域(yu)、黃(huang)河流(liu)域(yu)下(xia)游、長江(jiang)(jiang)流(liu)域(yu)上游、珠(zhu)江(jiang)(jiang)流(liu)域(yu)下(xia)游降(jiang)(jiang)水偏多(duo),有(you)利(li)于“兩(liang)遷(qian)”害蟲(chong)降(jiang)(jiang)落和病害流(liu)行(xing);登陸我(wo)國的(de)(de)(de)熱帶氣旋個(ge)數為(wei)7~9個(ge),較常年(平均(jun)7個(ge))偏多(duo),增加了(le)“兩(liang)遷(qian)”害蟲(chong)遷(qian)移區域(yu)的(de)(de)(de)不確(que)定(ding)性(xing)和細菌性(xing)病害的(de)(de)(de)流(liu)行(xing)風(feng)險。
(病蟲害測報處)