徐學(xué)欣,王 東
(1山東農(nóng)業(yè)大學(xué)農(nóng)學(xué)院/作物生物學(xué)國(guó)家重點(diǎn)實(shí)驗(yàn)室/農(nóng)業(yè)部作物生理生態(tài)與耕作重點(diǎn)實(shí)驗(yàn)室,山東泰安 271018;2中國(guó)農(nóng)業(yè)大學(xué)農(nóng)學(xué)院,北京 100193)
微噴補(bǔ)灌對(duì)冬小麥旗葉衰老和光合特性及產(chǎn)量和水分利用效率的影響
徐學(xué)欣1,2,王 東1
(1山東農(nóng)業(yè)大學(xué)農(nóng)學(xué)院/作物生物學(xué)國(guó)家重點(diǎn)實(shí)驗(yàn)室/農(nóng)業(yè)部作物生理生態(tài)與耕作重點(diǎn)實(shí)驗(yàn)室,山東泰安 271018;2中國(guó)農(nóng)業(yè)大學(xué)農(nóng)學(xué)院,北京 100193)
【目的】探明微噴補(bǔ)灌對(duì)冬小麥開(kāi)花后旗葉衰老和光合特性、籽粒灌漿速率、產(chǎn)量和水分利用效率的影響,為小麥節(jié)水高產(chǎn)提供重要技術(shù)支持?!痉椒ā坑?011—2013年冬小麥生長(zhǎng)季,選用高產(chǎn)冬小麥品種濟(jì)麥22,設(shè)置全生育期不灌水(W0)、微噴補(bǔ)灌(W1)和傳統(tǒng)畦灌(W2)處理,研究小麥開(kāi)花后旗葉水勢(shì)、超氧化物歧化酶(superoxide dismutase,SOD)和過(guò)氧化氫酶(catalase,CAT)活性、葉綠素?zé)晒鈪?shù)、群體光合速率和籽粒灌漿速率等的差異。W1與W2處理的灌水時(shí)期一致,均于小麥拔節(jié)期和開(kāi)花期各灌水1次。W1處理采用小麥專用微噴帶(ZL201220356553.7)補(bǔ)充灌溉,灌水前測(cè)定土壤含水量。兩年度小麥拔節(jié)期均設(shè)定0—140 cm土層土壤目標(biāo)相對(duì)含水量為70%,第一年和第二年小麥開(kāi)花期設(shè)定0—140 cm土層土壤目標(biāo)相對(duì)含水量分別為70%和65%,根據(jù)灌水定額公式計(jì)算所需補(bǔ)灌水量。W2處理采用傳統(tǒng)畦灌方式灌溉,改口成數(shù)為90%,即當(dāng)水流前鋒到達(dá)畦長(zhǎng)長(zhǎng)度的90%位置時(shí)停止灌水,用水表計(jì)量實(shí)際灌水量。W1與W2處理試驗(yàn)小區(qū)的規(guī)格一致,畦寬(左側(cè)畦梗中心線至右側(cè)畦梗中心線的垂直距離)2 m,畦梗寬0.4 m,畦長(zhǎng)60 m,面積120 m2。小區(qū)間設(shè)1.0 m保護(hù)行。每小區(qū)等行距種植8行小麥,實(shí)際行距22.9 cm。W1處理的每個(gè)試驗(yàn)小區(qū)在自邊行向內(nèi)數(shù)第4行與第5行小麥之間沿小麥種植行向(畦長(zhǎng)方向)鋪設(shè)一條專用微噴帶。微噴帶進(jìn)水端裝有壓力表、水表和閘閥,進(jìn)水端水壓設(shè)為0.02 MPa。灌溉水水源為井水,從水源至微噴帶和畦田進(jìn)水端采用PVC水龍帶輸水。畦灌的單寬流量為4.6—5.2 L·m-1·s-1?!窘Y(jié)果】?jī)赡甓任娧a(bǔ)灌處理在小麥拔節(jié)期和開(kāi)花期的補(bǔ)灌水量分別為21.3—96.0 mm和29.0—38.5 mm,灌水分布均勻系數(shù)達(dá)87.9%—97.0%,不低于傳統(tǒng)畦灌處理,而全生育期總灌水量比傳統(tǒng)畦灌處理減少33.2—70.8 mm,節(jié)水21.0%—54.2%。微噴補(bǔ)灌處理開(kāi)花后旗葉水勢(shì)、SOD和CAT活性、丙二醛含量、旗葉最大光化學(xué)效率、實(shí)際光化學(xué)效率,及群體光合速率和籽粒灌漿速率、籽粒產(chǎn)量均與全生育期灌2水的傳統(tǒng)畦灌處理無(wú)顯著差異,但水分利用效率提高2.1—2.9 kg·hm-2·mm-1,達(dá)21.6—23.2 kg·hm-2·mm-1。【結(jié)論】小麥拔節(jié)期和開(kāi)花期微噴補(bǔ)灌可以根據(jù)灌水前的降水量和土壤含水量狀況及時(shí)調(diào)節(jié)補(bǔ)灌水量,并實(shí)施精確、均勻灌溉,適量供給小麥高產(chǎn)生理需水,挖掘出小麥節(jié)水的更大潛力。
普通小麥;微噴;補(bǔ)灌;畦灌;旗葉衰老;光合特性;產(chǎn)量;水分利用效率
【研究意義】截至2010年,中國(guó)人均水資源占有量與20世紀(jì)五六十年代相比減少了50%左右,降水量減少 2.8%,地表水資源和水資源總量分別減少5.2%和3.6%,其中,以海河和黃河流域最為突出[1],而該地區(qū)農(nóng)業(yè)用水占總用水量的70.4%[2],水資源短缺威脅糧食安全。如何節(jié)水灌溉、提高水分利用效率是該地區(qū)小麥生產(chǎn)亟需解決的技術(shù)難題?!厩叭搜芯窟M(jìn)展】小麥開(kāi)花后遭遇水分脅迫,葉片超氧化物歧化酶(superoxide dismutase,SOD)和過(guò)氧化氫酶(catalase,CAT)活性均降低[3]。細(xì)胞代謝失調(diào),產(chǎn)生過(guò)剩的活性氧自由基,特別是引發(fā)或加劇膜脂質(zhì)過(guò)氧化產(chǎn)生丙二醛(malondialdehyde,MDA),造成細(xì)胞膜系統(tǒng)損傷,使其膜透性增高,葉綠素遭到破壞,植株早衰[4]。進(jìn)而導(dǎo)致籽粒灌漿時(shí)間縮短,粒重降低[5]。拔節(jié)期和開(kāi)花期適時(shí)按需補(bǔ)灌,能顯著提高小麥開(kāi)花后 0—24 d期間的旗葉 SOD和過(guò)氧化氫酶(catalase,CAT)活性,降低MDA含量,增強(qiáng)旗葉光合同化能力[6]。然而,當(dāng)前黃淮海地區(qū)小麥灌溉多采用畦灌,灌水量無(wú)法控制,難以實(shí)施按需精量補(bǔ)灌,制約水分利用效率的提高[7-8]。與傳統(tǒng)畦灌相比,噴灌和滴灌能有效控制每次灌水定額,成為當(dāng)前節(jié)水灌溉的重要設(shè)施[9-10]。微噴帶灌溉是在噴灌和滴灌的基礎(chǔ)上發(fā)展起來(lái)的一種新型灌溉方式,它利用微噴帶[11]將水均勻地噴灑在田間,所用設(shè)施相對(duì)簡(jiǎn)單、廉價(jià),易于收放[12-13]。然而,目前生產(chǎn)上常用的微噴帶帶型和噴孔等設(shè)計(jì)僅適于在低稈或大行距作物上應(yīng)用[14-15]。小麥生育中后期采用傳統(tǒng)的微噴帶灌溉,噴出的水流會(huì)被密集的小麥莖稈阻擋,射程和噴灑寬度大幅下降,噴水均勻度嚴(yán)重降低,難以實(shí)現(xiàn)節(jié)水灌溉。山東農(nóng)業(yè)大學(xué)前期發(fā)明的小麥專用微噴帶(ZL201220356553.7)[16],解決了小麥生育中后期由于行距窄、莖稈和葉片密集阻擋微噴帶噴射水流,降低噴灑幅度和均勻度的問(wèn)題,顯著提高灌溉水分布均勻系數(shù)[17-18],適于麥田實(shí)施按需精量補(bǔ)灌,有較好的推廣應(yīng)用前景[19]。【本研究切入點(diǎn)】前期的研究多是對(duì)不同微噴帶帶型的比較,關(guān)于微噴補(bǔ)灌與傳統(tǒng)畦灌的比較鮮有報(bào)道。在這兩種灌溉方式下,小麥產(chǎn)量和水分利用效率的差異亟待探討。【擬解決的關(guān)鍵問(wèn)題】本文擬研究小麥開(kāi)花后旗葉衰老、光合及葉綠素?zé)晒馓匦詫?duì)微噴補(bǔ)灌和傳統(tǒng)畦灌 2種灌溉方式的反應(yīng),探索2種灌溉方式對(duì)小麥產(chǎn)量和水分利用效率調(diào)節(jié)的生理基礎(chǔ),為小麥節(jié)水高產(chǎn)栽培提供理論依據(jù)和技術(shù)支持。
1.1研究區(qū)概況
試驗(yàn)于2011—2013年冬小麥生長(zhǎng)季,在山東省兗州市小孟鎮(zhèn)史家王子村(35.41°N,116.41°E)大田進(jìn)行,該區(qū)屬半濕潤(rùn)暖溫帶氣候,年均溫13.6℃。播種前試驗(yàn)地0—20 cm土層土壤養(yǎng)分狀況和小麥生長(zhǎng)季降水量見(jiàn)表1,播前0—200 cm土層土壤水分狀況見(jiàn)表2。試驗(yàn)田田間縱向坡度為2.18‰。
表1 試驗(yàn)地 0—20 cm土層土壤養(yǎng)分狀況及冬小麥生長(zhǎng)季降水量Table 1 Soil nutrient condition in 0-20 cm soil layer of the experimental field and precipitation during the growth season of winter wheat
表2 試驗(yàn)地 0—200 cm土層土壤含水量Table 2 Soil water content in 0-200 cm soil layers of the experimental field (%)
1.2試驗(yàn)設(shè)計(jì)
設(shè)置全生育期不灌水(W0)、微噴補(bǔ)灌(W1)和傳統(tǒng)畦灌(W2)3個(gè)處理。W1與W2處理的灌水時(shí)期一致,均于小麥拔節(jié)期和開(kāi)花期各灌水1次。W1處理采用小麥專用微噴帶(ZL201220356553.7)補(bǔ)充灌溉,灌水前測(cè)定土壤含水量。兩年度小麥拔節(jié)期均設(shè)定0—140 cm土層土壤目標(biāo)相對(duì)含水量為70%,第一年和第二年小麥開(kāi)花期設(shè)定0—140 cm土層土壤目標(biāo)相對(duì)含水量分別為70%和65%。根據(jù)灌水定額公式計(jì)算所需補(bǔ)灌水量(CIR,mm)。
式中:Dh(cm)為補(bǔ)灌的擬濕潤(rùn)土層深度,即140 cm,γbd(g·cm-3)為該擬濕潤(rùn)土層土壤容重,θt(mg·g-1)為目標(biāo)土壤含水量,即田間持水量乘以目標(biāo)土壤相對(duì)含水量,θn(mg·g-1)為灌水前擬濕潤(rùn)土層土壤平均含水量。
W2處理采用傳統(tǒng)畦灌方式灌溉,改口成數(shù)設(shè)為90%,即當(dāng)水流前鋒到達(dá)畦長(zhǎng)長(zhǎng)度的90%位置時(shí)停止灌水。采用水表計(jì)量實(shí)際灌水量。
每處理3次重復(fù),試驗(yàn)小區(qū)畦寬(左側(cè)畦梗中心線至右側(cè)畦梗中心線的垂直距離)2 m,畦面寬1.6 m,畦梗寬0.4 m,畦長(zhǎng)60 m,面積120 m2,小區(qū)間設(shè)1.0 m保護(hù)行。每小區(qū)等行距種植8行小麥,實(shí)際行距22.9 cm。W1處理的每個(gè)試驗(yàn)小區(qū)在自邊行向內(nèi)數(shù)第4行與第5行小麥之間沿小麥種植行向(畦長(zhǎng)方向)鋪設(shè)一條專用微噴帶。微噴帶進(jìn)水端裝有壓力表、水表和閘閥,進(jìn)水端水壓設(shè)為0.02 MPa。灌溉水水源為井水,從水源至微噴帶和畦田進(jìn)水端采用PVC水龍帶輸水。畦灌的單寬流量為4.6—5.2 L·m-1·s-1。
兩年度供試品種均為濟(jì)麥22,小麥播種前,將前茬玉米秸稈全部粉碎翻壓還田,底施純N 105 kg·hm-2、P2O5150 kg·hm-2和K2O 150 kg·hm-2,拔節(jié)期追施N 135 kg·hm-2。用尿素作氮肥,磷酸二銨作氮肥和磷肥,氯化鉀作鉀肥。分別于2011年10月10日和2012年10月9日播種,3葉1心期定苗,基本苗為180 株/m2,其他管理措施同一般高產(chǎn)田。
1.3測(cè)定項(xiàng)目與方法
1.3.1灌溉水在土壤中水平分布均勻性的計(jì)算 灌溉水在土壤中的水平分布均勻性采用克里斯琴森均勻系數(shù)Cμ表示[22],計(jì)算公式為:
式中:hi為第i取土點(diǎn)灌水后第3天與灌水前1 d 0—40 cm或0—200 cm土層土壤平均貯水量之差(mm);為n個(gè)取土點(diǎn)hi的平均值(mm);n為取土點(diǎn)數(shù),本試驗(yàn)各小區(qū)均設(shè)有60個(gè)取樣點(diǎn),故n=60。
1.3.2旗葉水勢(shì)的測(cè)定 于開(kāi)花后0、10、20和30 d早上6:00前,每處理摘取旗葉12片,采用Psypro型露點(diǎn)水勢(shì)測(cè)量系統(tǒng)(Wescor,美國(guó))進(jìn)行旗葉水勢(shì)測(cè)定。
1.3.3旗葉SOD、CAT活性和MDA含量的測(cè)定 樣品采集和處理:在開(kāi)花后第0、7、14、21和28天,采集旗葉,每個(gè)處理3次重復(fù),每重復(fù)取15個(gè)旗葉,用錫箔紙包裹后立即放入液氮冷凍,隨后置-40℃冰柜保存待用。
酶液的制備:快速稱取0.5 g剪碎的旗葉放入研缽中,加5 mL pH=7.8的磷酸緩沖液(0.2 mol·L-1KH2PO4和0.2 mol·L-1K2HPO4),冰浴研磨,勻漿倒入離心管中,冷凍離心20 min(9 800 r/min),上清液(酶液)倒入試管中,置于0—4℃保存待用。
參照BEAUCHAMP等[23]方法測(cè)定SOD活性:取型號(hào)相同的試管,吸取20 μL的酶液,加入3 mL反應(yīng)液;同時(shí)取四支試管,三支作對(duì)照,一支作為空白對(duì)照(不加酶液,以緩沖液代替);空白置暗處,對(duì)照(CK)與酶液同置于4 000 lx環(huán)形日光燈的光照培養(yǎng)箱照光30 min,遮光保存,以空白調(diào)零,560 nm比色。SOD反應(yīng)液為0.05 mol·L-1磷酸緩沖液(pH=7.8)、130 mmol·L-1Met(甲硫氨酸)、750 μmol·L-1四氮唑藍(lán)(NBT)、100 μmol·L-1EDTA-Na2、20 μmol·L-1FD(核黃素)、H2O按照15∶3∶3∶3∶3∶2.5比例混勻。
參照TAN等[24]方法測(cè)定CAT活性:50 μL酶液+2.5 mL反應(yīng)液,240 nm比色,每隔1 min讀數(shù)1次,共讀數(shù)3次。反應(yīng)液為0.1 mol·L-1的H2O25 mL+0.1 mol·L-1的pH 7.0的磷酸緩沖液20 mL(即按1∶4的比例)混勻。
參照QUAN等[25]方法測(cè)定MDA含量:1 mL酶液+2 mL 0.6%的TBA,封口沸水浴15 min,迅速冷卻后再離心,取上清液,在600、532和450 nm 3個(gè)波長(zhǎng)下比色。
1.3.4旗葉熒光參數(shù)的測(cè)定 于開(kāi)花后 7、14、21 和28 d上午9:00—11:00,在田間自然光照下選取生長(zhǎng)一致且受光方向相同的旗葉12片,分別夾上金屬片打開(kāi)的暗適應(yīng)夾,采用FMS-2型熒光儀測(cè)定旗葉實(shí)際光化學(xué)效率(actual photochemical efficiency of PSⅡ,ΦPSⅡ),迅速關(guān)閉金屬片進(jìn)行暗適應(yīng) 30 min后,測(cè)定旗葉暗適應(yīng)下的初始熒光值(minimal fluorescence,F(xiàn)0)和最大熒光值(maximal fluorescence,F(xiàn)m),重復(fù)測(cè)定 10次。PSⅡ潛在最大光化學(xué)量子效率(Fv/Fm)用以下公式[26]計(jì)算:
1.3.5群體光合速率測(cè)定 參照董樹(shù)亭等[27]的方法略有改進(jìn)。采用GXH-3051型紅外CO2分析儀,分別于小麥開(kāi)花后0、10、20和30 d晴天上午9:30—12:00在自然光照下測(cè)定群體光合速率。同化箱長(zhǎng)、寬、高分別為100、100和120 cm。框架外罩以透光性良好的投影膜,透光率95%以上。同化箱內(nèi)裝有一個(gè)80 W的風(fēng)扇,用于攪勻箱內(nèi)氣體。測(cè)定時(shí)每隔20 s讀1次數(shù),同步測(cè)定土壤呼吸。計(jì)算公式為:
式中:CAP為群體表觀凈光合速率(μmolCO2m-2·h-1),ΔC為作物群體凈光合實(shí)際同化CO2濃度差(10-6);V為同化箱體積(m3);ΔM為測(cè)定時(shí)間(s);T為同化箱溫度(℃);L為測(cè)定群體所占的土地面積(m2)。
1.3.6籽粒灌漿速率和產(chǎn)量的測(cè)定 在小麥初花期,每小區(qū)選擇同日開(kāi)花且長(zhǎng)相、長(zhǎng)勢(shì)、穗子大小基本一致、無(wú)病蟲(chóng)害的單莖80個(gè)掛牌標(biāo)記,從開(kāi)花后7 d開(kāi)始取樣,以后每7天取樣1次,直至完全成熟。每小區(qū)每次取樣10穗,帶回室內(nèi),每穗人工剝出所有籽粒,立即在105℃烘箱內(nèi)殺青20 min,然后恒溫75℃烘至恒重,稱重,計(jì)算粒重及灌漿速率。
成熟期沿畦長(zhǎng)方向,將各試驗(yàn)小區(qū)距畦首 1—2 m、14.5—15.5 m、29.5—30.5 m、44.5—45.5 m、58—59 m(寬度均為 2 m)范圍內(nèi)的小麥全部收獲脫粒,每小區(qū)總收獲面積為 10 m2,待籽粒自然風(fēng)干至含水率為12.5%時(shí)分別稱重,計(jì)算平均產(chǎn)量。
1.3.7農(nóng)田耗水量和水分利用效率的測(cè)定計(jì)算
計(jì)算公式[28]為:
式中:ET1-2為階段耗水量(mm);M為階段內(nèi)的灌水量(mm);P0為階段內(nèi)有效降水量(mm);K為階段內(nèi)的地下水補(bǔ)給量(mm),當(dāng)?shù)叵滤裆畲笥? m時(shí),K值可以忽略不計(jì),本試驗(yàn)的地下水埋深在5 m以下,故地下水補(bǔ)給量可視為0;Si為階段土壤貯水消耗量,其計(jì)算公式為:
式中:i為土層編號(hào);n為總土層數(shù);ri為第i層土壤容重(g·cm-3);Hi為第i層土壤厚度(cm);θi1和θi2分別為階段初和階段末第i層的土壤含水量(%)。
參照SEPASKHAH等[29]方法計(jì)算水分利用效率:
水分利用效率(kg·hm-2·mm-1)=籽粒產(chǎn)量(kg·hm-2)/農(nóng)田耗水量(mm)
1.4數(shù)據(jù)處理
采用Microsoft Excel 2003對(duì)數(shù)據(jù)進(jìn)行繪圖,采用DPS 7.05統(tǒng)計(jì)分析軟件對(duì)各處理數(shù)據(jù)進(jìn)行單因素方差分析,用LSD法進(jìn)行差異顯著性檢驗(yàn)(α=0.05)。
2.1不同灌溉方式對(duì)灌水量的影響
微噴補(bǔ)灌(W1)和傳統(tǒng)畦灌(W2)處理的灌水量如表3所示。W1處理的灌水量在2011—2012年度拔節(jié)期和兩年度開(kāi)花期均顯著低于W2處理。兩年度,W1處理在拔節(jié)期和開(kāi)花期的灌水量比W2處理分別減少了4.2—52.5 mm和18.3—29.0 mm,全生育期總灌水量減少了33.2—70.8 mm,節(jié)水21.0 %—54.2%。
表3 各處理拔節(jié)期、開(kāi)花期和全生育期灌水量Table 3 Amount of irrigation in different treatments at jointing,anthesis and during whole growth season (mm)
2.2不同灌溉方式對(duì)灌溉水分布均勻系數(shù)的影響
如表4所示,兩年度拔節(jié)期灌水后,W1處理0—40 和0—200 cm土層灌溉水分布均勻系數(shù)分別在93.2%—96.4%和89.2%—94.3%范圍內(nèi),與W2處理的無(wú)顯著差異。兩年度開(kāi)花期灌水后,W1處理0—40 cm土層灌溉水分布均勻系數(shù)在95.9%—97.0%范圍內(nèi),與W2處理的無(wú)顯著差異;但2012—2013年度開(kāi)花期灌水后,W1處理0—200 cm土層灌溉水分布均勻系數(shù)為87.9%,顯著高于W2處理的。說(shuō)明采用微噴補(bǔ)灌,盡管灌水量較少,并沒(méi)有降低灌溉水在田間分布的均勻度。
2.3不同灌溉方式對(duì)花后旗葉水勢(shì)的影響
開(kāi)花后旗葉水勢(shì)變化如圖1所示,兩年度規(guī)律一致。隨著開(kāi)花后天數(shù)的增加,各處理旗葉水勢(shì)呈下降趨勢(shì)。全生育期不灌水處理(W0)在開(kāi)花后0、10、20和30 d的旗葉水勢(shì)均顯著低于W1和W2處理,W1處理的旗葉水勢(shì)與W2處理的無(wú)顯著差異。
2.4不同灌溉方式對(duì)旗葉SOD、CAT活性和MDA含量的影響
開(kāi)花后旗葉SOD、CAT活性和MDA含量變化如圖2所示,兩年度規(guī)律一致。旗葉SOD活性在開(kāi)花后0—7 d期間相對(duì)穩(wěn)定,開(kāi)花7 d后呈逐漸下降趨勢(shì);旗葉CAT活性在開(kāi)花后呈先升后降趨勢(shì),以開(kāi)花后7 d最高;旗葉MDA含量在開(kāi)花后0—7 d期間相對(duì)穩(wěn)定,開(kāi)花7 d后呈逐漸升高趨勢(shì)。W1和W2處理開(kāi)花后旗葉SOD和CAT活性顯著高于W0處理的,MDA含量顯著低于W0處理的;W1處理與W2處理之間則無(wú)顯著差異。說(shuō)明在灌水次數(shù)和時(shí)期相同的條件下,微噴補(bǔ)灌對(duì)小麥旗葉衰老的調(diào)節(jié)效果與傳統(tǒng)畦灌無(wú)顯著差異。
表4 不同處理的灌溉水分布均勻系數(shù)Table 4 Irrigation water distribution uniformity in different treatments (%)
圖1 不同處理開(kāi)花后的旗葉水勢(shì)Fig.1 Flag leaves water potential after anthesis in different treatments
2.5不同灌溉方式對(duì)花后旗葉熒光參數(shù)的影響
開(kāi)花后旗葉熒光參數(shù)變化如圖3所示,兩年度規(guī)律一致。W1處理開(kāi)花后的旗葉最大光化學(xué)效率和實(shí)際光化學(xué)效率均與W2處理的無(wú)顯著差異,但兩處理開(kāi)花后21和28 d的旗葉最大光化學(xué)效率,及開(kāi)花后7 —28 d的旗葉實(shí)際光化學(xué)效率均顯著高于W0處理。
2.6不同灌溉方式對(duì)小麥群體光合速率的影響
各處理小麥開(kāi)花后群體光合速率如圖4所示,兩年度規(guī)律一致。全生育期不灌水處理的小麥群體光合速率在開(kāi)花后呈下降趨勢(shì),且顯著低于W1和W2處理的。W1和W2處理的群體光合速率在開(kāi)花后呈先升高后降低的變化趨勢(shì),均在開(kāi)花后10 d達(dá)到高峰,W1與W2處理之間無(wú)顯著差異。說(shuō)明在灌水次數(shù)和時(shí)期相同的條件下,微噴補(bǔ)灌雖然減少了灌水量,但小麥開(kāi)花后的群體光合速率并不比傳統(tǒng)畦灌的低。
2.7不同灌溉方式對(duì)小麥籽粒灌漿的影響
各處理籽粒灌漿速率如圖5所示,兩年度規(guī)律一致。W0處理在開(kāi)花后7 d的籽粒灌漿速率顯著高于W1和W2處理,但開(kāi)花14 d后則顯著低于W1和W2處理。W1處理在開(kāi)花后7—35 d的籽粒灌漿速率與W2處理的無(wú)顯著差異。
2.8不同灌溉方式對(duì)籽粒產(chǎn)量、耗水量和水分利用效率的影響
各處理籽粒產(chǎn)量、耗水量和水分利用效率如表 5所示。兩年度均表現(xiàn)為,W0處理的籽粒產(chǎn)量和耗水量顯著低于W1和W2處理;W1處理的籽粒產(chǎn)量與W2處理的無(wú)顯著差異,但耗水量顯著低于W1處理的,差值達(dá) 47.6—52.2 mm;水分利用效率顯著高于W1處理的,差值達(dá)2.1—2.9 kg·hm-2·mm-1。說(shuō)明在灌水次數(shù)和時(shí)期相同的條件下,微噴補(bǔ)灌以較低的耗水量獲得了與傳統(tǒng)畦灌相同的產(chǎn)量。
圖2 不同處理開(kāi)花后的旗葉SOD、CAT活性和MDA含量Fig.2 Superoxide dismutase (SOD),catalase (CAT) activities and malondialdehyde (MDA) content of flag leaves after anthesis in different treatments
表5 不同處理的籽粒產(chǎn)量、耗水量和水分利用效率Table 5 Grain yield,evapotranspiration and water use efficiency in different treatments
圖3 不同處理開(kāi)花后的旗葉熒光參數(shù)Fig.3 Chlorophyll fluorescence parameters of flag leaves after anthesis in different treatments
圖4 不同處理開(kāi)花后的群體光合速率Fig.4 Canopy apparent photosynthetic rate after anthesis in different treatments
灌溉水分布均勻度是評(píng)價(jià)灌溉質(zhì)量的重要指標(biāo)之一,對(duì)作物產(chǎn)量有重要影響,常用灌溉水分布均勻系數(shù)表示[30]。前人研究表明,采用畦灌,在畦田坡度低于7.6‰、畦長(zhǎng)60 m的條件下,灌溉水分布均勻系數(shù)與畦寬呈二次曲線關(guān)系,畦寬為2 m時(shí)灌溉水分布均勻系數(shù)最高,達(dá)到84%,畦田過(guò)寬或太窄,則導(dǎo)致灌溉水在畦首和畦尾的入滲深度不一,灌溉水分布均勻系數(shù)降低[31]。還有研究表明,畦灌的改口成數(shù)對(duì)灌溉水分布均勻度亦有顯著影響,在畦田坡度為2.14‰,畦長(zhǎng)和畦寬分別為80和2 m的條件下,小麥拔節(jié)期畦灌,當(dāng)水流前鋒到達(dá)畦田長(zhǎng)度的90%時(shí)停止灌水,灌溉水分布均勻系數(shù)可達(dá)93.4%—93.8%[32]。采用噴灌,小麥全生育期噴灌4—5次,在供水壓力為0.3 MPa,單次灌水量為22.2—56.3 mm的條件下,灌溉水分布均勻系數(shù)可達(dá)60%—88%[33-34]。前人研究表明[35],微噴帶每組噴孔由3個(gè)增加到12個(gè),灌溉水分布均勻系數(shù)由24.6%增加到78.3%,工作壓力由0.03 kPa增加到 0.05 kPa,灌溉水分布均勻系數(shù)由 34.4%增加到73.9%。本研究采用的小麥專用微噴帶,直徑51 mm,每組 6個(gè)噴孔,最小噴射角為 80°,最大噴射角為88°[16]。在小麥拔節(jié)期補(bǔ)灌水量為21.3—96.0 mm,進(jìn)水端水壓為0.02 MPa的條件下,灌水后0—40 cm和0—200 cm土層灌溉水分布均勻系數(shù)分別為93.2%—96.4%和 89.2%—94.3%;在小麥開(kāi)花期補(bǔ)灌水量為29.0—38.5 mm的條件下,灌水后0—40 cm和0—200 cm土層灌溉水分布均勻系數(shù)分別為95.9%—97.0%和87.9%—93.5%,均不低于本研究中相同畦田規(guī)格、改口成數(shù)為90%的畦灌處理。
圖5 不同處理的籽粒灌漿速率Fig.5 Grain filling rate in different treatments
小麥開(kāi)花后葉片水勢(shì)與0—60 cm土層土壤含水量呈正相關(guān)[36-37]。有研究認(rèn)為,小麥旗葉水勢(shì)對(duì)土壤相對(duì)含水量的響應(yīng)閾值是60%,高于該值繼續(xù)增加土壤含水量,旗葉水勢(shì)無(wú)明顯提高[38]。土壤相對(duì)含水量維持在60%以上亦能顯著提高旗葉SOD、CAT和POD活性,延緩葉片衰老[39-40]。本研究在拔節(jié)期微噴補(bǔ)灌使0—140 cm土層土壤平均相對(duì)含水量達(dá)到70%的基礎(chǔ)上,再于開(kāi)花期微噴補(bǔ)灌,使0—140 cm土層土壤平均相對(duì)含水量達(dá)到65%或70%,小麥旗葉水勢(shì)、SOD 和CAT活性與灌水較多的畦灌處理無(wú)顯著差異,進(jìn)一步證明土壤相對(duì)含水量在達(dá)到一定閾值后,小麥旗葉水勢(shì)和抗氧化酶活性對(duì)土壤含水量的反應(yīng)不再敏感,這為適量補(bǔ)灌保障作物正常的生理需水實(shí)現(xiàn)節(jié)水高產(chǎn)提供了理論基礎(chǔ)。
前人研究表明,春季不灌水處理的小麥群體光合速率顯著低于灌水處理,而春灌兩水與春灌四水處理之間無(wú)顯著差異[41]??偣喔攘吭?—150 mm范圍內(nèi),隨灌溉次數(shù)增多或灌溉時(shí)期后移,小麥群體光合速率增加,但總灌溉量超過(guò)150 mm后,群體光合速率反而降低[42]。還有研究表明,小麥開(kāi)花后旗葉光系統(tǒng)Ⅱ(PSⅡ)原初光能轉(zhuǎn)化效率(Fv/Fm)和潛在活性(Fv/F0)在土壤相對(duì)含水量為60%—70%時(shí)最高,而當(dāng)土壤相對(duì)含水量低于60%或高于80%時(shí)則顯著降低[43]。本研究在小麥一生中僅于拔節(jié)期和開(kāi)花期灌溉兩水,畦灌灌水量分別為73.8—100.2 mm和56.8—58.0 mm,開(kāi)花后旗葉最大光化學(xué)效率、實(shí)際光化學(xué)效率、群體光合速率均顯著高于不灌水的處理,而微噴補(bǔ)灌處理的灌水量比畦灌處理分別減少了4.2—52.5 mm和18.3—29.0 mm,全生育期總灌水量減少了33.2—70.8 mm,節(jié)水21.0%—54.2%,小麥開(kāi)花后旗葉熒光特性、群體光合速率和籽粒產(chǎn)量與本研究中的畦灌處理相比無(wú)顯著差異,說(shuō)明微噴補(bǔ)灌可以在畦灌節(jié)水模式的基礎(chǔ)上進(jìn)一步挖掘小麥節(jié)水高產(chǎn)的潛力。
本研究結(jié)果還發(fā)現(xiàn),2011—2012年度播種至拔節(jié)期降水量較多,達(dá)149.0 mm,拔節(jié)期的微噴補(bǔ)灌水量顯著低于傳統(tǒng)畦灌處理,而2012—2013年度播種至拔節(jié)期降水量較少,僅為92.0 mm,拔節(jié)期的微噴補(bǔ)灌水量比傳統(tǒng)畦灌處理僅減少了4.2 mm,說(shuō)明采用補(bǔ)灌的方法可以根據(jù)小麥生育期間的降水量和土壤含水量狀況及時(shí)調(diào)節(jié)灌溉水量,而小麥專用微噴帶可以于小麥生育中后期實(shí)施精量灌溉,且具有較高的灌溉水分布均勻度,二者的結(jié)合可以為小麥節(jié)水高產(chǎn)栽培提供技術(shù)支持。
采用小麥專用微噴帶在拔節(jié)期和開(kāi)花期進(jìn)行微噴補(bǔ)灌具有根據(jù)土壤水分狀況按需補(bǔ)給、精確灌溉的優(yōu)勢(shì),灌溉水分布均勻系數(shù)可達(dá)87.9%—97.0%,比全生育期灌兩水的畦灌處理減少 33.2—70.8 mm的灌水量,節(jié)水21.0%—54.2%,而且能維持小麥開(kāi)花后較高的旗葉水勢(shì)、SOD和CAT活性,延緩葉片衰老,保持較高的群體光合速率和籽粒灌漿速率,比畦灌處理提高水分利用效率2.1—2.9 kg·hm-2·mm-1。
References
[1] 康紹忠. 水安全與糧食安全. 中國(guó)生態(tài)農(nóng)業(yè)學(xué)報(bào),2014,22(8): 880-885. KANG S Z. Towards water and food security in China. Chinese Journal of Eco-Agriculture,2014,22(8): 880-885. (in Chinese)
[2] 劉布春,梅旭榮,李玉中,楊有祿. 農(nóng)業(yè)水資源安全的定義及其內(nèi)涵和外延. 中國(guó)農(nóng)業(yè)科學(xué),2006,39(5): 947-951. LIU B C,MEI X R,LI Y Z,YANG Y L. The connotation and extension of agricultural water resources security. Scientia Agricultura Sinica,2006,39(5): 947-951. (in Chinese)
[3] 趙長(zhǎng)星,馬東輝,王月福,林琪. 施氮量和花后土壤含水量對(duì)小麥旗葉衰老及粒重的影響. 應(yīng)用生態(tài)學(xué)報(bào),2008,19(11): 2388-2393. ZHAO C X,MA D H,WANG Y F,LIN Q. Effects of nitrogen application rate and post-anthesis soil moisture content on the flag leaf senescence and kernel weight of wheat. Chinese Journal of Applied Ecology,2008,19(11): 2388-2393. (in Chinese)
[4] 馮佰利,高小麗,王長(zhǎng)發(fā),張嵩午,李生秀. 干旱條件下不同溫型小麥葉片衰老與活性氧代謝特性的研究. 中國(guó)生態(tài)農(nóng)業(yè)學(xué)報(bào),2005,13(4): 74-76. FENG B L,GAO X L,WANG C F,ZHANG S W,LI S X. Leaf senescence and active oxygen metabolism of different -type wheats under drought. Chinese Journal of Eco-Agriculture,2005,13(4): 74-76. (in Chinese)
[5] SAWHNEY V,SINGH D P. Effect of chemical desiccation at the post-anthesis stage on some physiological and biochemical changes in the flag leaves of contrasting wheat genotypes. Field Crops Research,2002,77: 1-6.
[6] WANG D,YU Z W,WHITE P J. The effect of supplemental irrigation after jointing on leaf senescence and grain filling in wheat. Field Crops Research,2013,151: 35-44.
[7] 滿建國(guó),王東,張永麗,石玉,于振文. 不同噴射角微噴帶灌溉對(duì)土壤水分布與冬小麥耗水特性及產(chǎn)量的影響. 中國(guó)農(nóng)業(yè)科學(xué),2013,46(24): 5098-5112. MAN J G,WANG D,ZHANG Y L,SHI Y,YU Z W. Effects of irrigation with micro-sprinkling hoses of different sprinkling angles on soil water distribution and water consumption characteristics and grain yield of winter wheat. Scientia Agricultura Sinica,2013,46(24): 5098-5112. (in Chinese)
[8] FANG Q X,MA L,GREEN T R,YU Q,WANG T D,AHUJA L R. Water resources and water use efficiency in the North China Plain: Current status and agronomic management options. Agricultural Water Management,2010,97: 1102-1116.
[9] 宮飛,陳阜,楊曉光,苑麗娟. 噴灌對(duì)冬小麥水分利用的影響. 中國(guó)農(nóng)業(yè)大學(xué)學(xué)報(bào),2001,6(5): 30-34. GONG F,CHEN F,YANG X G,YUAN L J. Effects of sprinkler irrigation on water use of winter wheat. Journal of China Agricultural University,2001,6(5): 30-34. (in Chinese)
[10] 陳靜,王迎春,李虎,王立剛,邱建軍,肖碧林. 滴灌施肥對(duì)免耕冬小麥水分利用及產(chǎn)量的影響. 中國(guó)農(nóng)業(yè)科學(xué),2014,47(10): 1966-1975. CHEN J,WANG Y C,LI H,WANG L G,QIU J J,XIAO B L. Effects of drip fertigation with no-tillage on water use efficiency and yield of winter wheat. Scientia Agricultura Sinica,2014,47(10): 1966-1975. (in Chinese)
[11] 中華人民共和國(guó)農(nóng)業(yè)部. NY/T 1361-2007,中華人民共和國(guó)農(nóng)業(yè)行業(yè)標(biāo)準(zhǔn)-農(nóng)業(yè)灌溉設(shè)備,微噴帶. 北京: 中國(guó)農(nóng)業(yè)出版社,2007. Ministry of Agriculture of the People’s Republic of China. NY/T1361-2007,Agricultural Industry Standards of the People's Republic of China,Agricultural Irrigation Equipment,Micro-Sprinkling Hose. Beijing: China Agriculture Press,2007. (in Chinese)
[12] 李英能. 對(duì)我國(guó)噴灌技術(shù)發(fā)展若干問(wèn)題的探討. 節(jié)水灌溉,2001(1): 1-3. LI Y N.A discussion on several problems of sprinkler irrigation technique development in China. Water Saving Irrigation,2001(1): 1-3. (in Chinese)
[13] 周斌,封俊,張學(xué)軍,吳政文,沈雪民. 微噴帶單孔噴水量分布的基本特征研究. 農(nóng)業(yè)工程學(xué)報(bào),2003,19(4): 101-103. ZHOU B,F(xiàn)ENG J,ZHANG X J,WU Z W,SHEN X M. Characteristics and indexes of water distribution of punched thin-soft tape for spray. Transactions of the Chinese Society of Agricultural Engeering,2003,19(4): 101-103. (in Chinese)
[14] 史宏志,高衛(wèi)鍇,常思敏,邸慧慧,王廷曉,楊素琴,王太運(yùn),王廣勝. 微噴灌水定額對(duì)煙田土壤物理性狀和養(yǎng)分運(yùn)移的影響. 河南農(nóng)業(yè)大學(xué)學(xué)報(bào),2009,43(5): 485-491. SHI H Z,GAO W K,CHANG S M,DI H H,WANG T X,YANG S Q,WANG T Y,WANG G S. Effect of irrigating water quota with micro-irrigation on soil physical properties and nutrient transport in different layers of tobacco soil. Journal of Henan Agricultural University,2009,45(5): 485-491. (in Chinese)
[15] KOUMANOV K S,HOPMANS J W,SCHWANKL L J,ANDREU L,TULI A. Application efficiency of micro-sprinkler irrigation of almond trees. Agricultural Water Management,1997,34: 247-263.
[16] 山東農(nóng)業(yè)大學(xué). 小麥專用微噴帶: 中國(guó),201220356553.7. 2013-02-06. Shandong Agricultural University. Micro-sprinkling hose special for wheat: China,201220356553.7. 2013-02-06. (in Chinese)
[17] MAN J G,WANG D,WHITE P J,YU Z W. The length of micro-sprinkling hoses delivering supplemental irrigation affects photosynthesis and dry matter production of winter wheat. Field Crops Research,2014,168: 65-74.
[18] MAN J G,YU J S,WHITE P J,GU S B,ZHANG Y L,GUO Q F,SHIY,WANG D. Effects of supplemental irrigation with micro-sprinkling hoses on water distribution in soil and grain yield of winter wheat. Field Crops Research,2014,161: 26-37.
[19] 牛西午,馮永平,董孟雄,董忠義. “簡(jiǎn)易微噴灌技術(shù)”及其在旱塬麥田應(yīng)用研究初報(bào). 水土保持通報(bào),1999,26(1): 31-35. NIU X W,F(xiàn)ENG Y P,DONG M X,DONG Z Y. Simple micro-sprinkling irrigation method and its application in dryland wheat production. Bulletin of Soil and Water Conservation,1999,26(1): 31-35. (in Chinese)
[20] CUENCA R H. Irrigation System Design: An Engineering Approach. Prentice Hall,Englewood Cliffs,New Jersey. 1989.
[21] JALILIAN J,MODARRES-SANAVY S A M,SABERALI S F,SADAT-ASILAN K. Effects of the combination of beneficial microbes and nitrogen on sunflower seed yields and seed quality traits under different irrigation regimes. Field Crops Research,2012,127: 26-34.
[22] CHRISTIANSEN J E. Irrigation by Sprinkling. California agricultural experiment station bulletin 670. University of California,Berkeley,CA,1942: 110-116.
[23] BEAUCHAMP C,F(xiàn)RIDOVICH I. Superoxide dismutase: Improved assay and an assay applicable to acrylamide gels. Analytical Biochemistry,1971,44: 276-287.
[24] TAN W,LIU J,DAI T,JING Q,CAO W,JIANG D. Alternations in photosynthesis and antioxidant enzyme activity in winter wheat subjected to post-anthesis water-logging. Photosynthetica,2008,46: 21-27.
[25] QUAN R D,SHANG M,ZHANG H,ZHAO Y X,ZHANG J R. Improved chilling tolerance by transformation with betA gene for the enhancement of glycinebetaine synthesis in maize. Plant Science,2004,166: 141-149.
[26] SAGARAM M,BURNS J K. Leaf chlorophyll fluorescence parameters and huanglongbing. Journal of the American Society for Horticultural Science,2009,134(2): 194-201.
[27] 董樹(shù)亭,高榮岐,胡昌浩,王群瑛,王空軍. 玉米花粒期群體光合性能與高產(chǎn)潛力研究. 作物學(xué)報(bào),1997,23(3): 318-325. DONG S T,GAO R Q,HU C H,WANG Q Y,WANG K J. Study of canopy photosynthesis property and high yield potential after anthesis in maize. Acta Agronomica Sinica,1997,23(3): 318-325. (in Chinese)
[28] 劉增進(jìn),李寶萍,李遠(yuǎn)華,崔遠(yuǎn)來(lái). 冬小麥水分利用效率與最優(yōu)灌溉制度的研究. 農(nóng)業(yè)工程學(xué)報(bào),2004,20(4): 58-63. LIU Z J,LI B P,LI Y H,CUI Y L. Research on the water use efficiency and optimal irrigation schedule of the winter wheat. Transactions of the Chinese Society of Agricultural Engineering,2004,20(4): 58-63. (in Chinese)
[29] SEPASKHAH A R,TAGAFTEH A. Yield and nitrogen leaching in rapeseed field under different nitrogen rates and water saving irrigation. Agricultural Water Management,2012,112: 55-62.
[30] 李久生. 噴灌均勻系數(shù)對(duì)土壤水分空間分布及作物產(chǎn)量影響的研究現(xiàn)狀. 農(nóng)業(yè)工程學(xué)報(bào),1998,14(2): 132-137. LI J S. A review on the effects of sprinkler uniformity on the spatial distributions of soil moisture and crop yield. Transcation of the Chinese Society of Agricultural Enggineering,1998,14(2): 132-137. (in Chinese)
[31] 李久生,饒敏杰. 地面灌溉水流特性及水分利用率的田間試驗(yàn)研究. 農(nóng)業(yè)工程學(xué)報(bào),2003,19(3): 54-58. LI J S,RAO M J. Field evaluation of water flow performance and application efficiency for border irrigation. Transactions of the Chinese Society of Agricultural Engineering,2003,19(3): 54-58. (in Chinese)
[32] 冀傳允,于振文,石玉,趙俊曄,王東. 不同畦灌改水成數(shù)對(duì)畦內(nèi)水分分布小麥耗水特性及產(chǎn)量的影響. 水土保持學(xué)報(bào),2014,28(2): 95-99,126. JI C Y,YU Z W,SHI Y,ZHAO J Y,WANG D. Effects of inflow cutoff for border irrigation on water distribution in the border,water consumption characteristics and grain yield of wheat. Journal of Soil and Water Conservation,2014,28(2): 95-99,126. (in Chinese)
[33] 李久生,饒敏杰,李蓓. 噴灌施肥灌溉均勻性對(duì)土壤硝態(tài)氮空間分布影響的田間試驗(yàn)研究. 農(nóng)業(yè)工程學(xué)報(bào),2005,21(3): 51-55.LI J S,RAO M J,LI B. Spatial distribution of nitrate in soil as aff ected by uniformity of sprinkler fertigation. Transactions of the Chinese Society of Agricultural Engineering,2005,21(3): 51-55. (in Chinese)
[34] 李久生,饒敏杰. 噴灌施肥均勻性對(duì)冬小麥產(chǎn)量影響的田間試驗(yàn)評(píng)估. 農(nóng)業(yè)工程學(xué)報(bào),2000,16(6): 38-42. LI J S,RAO M J. Field evaluation of yield response of winter wheat to uniformity of sprinkler applied fertilizer. Transactions of the Chinese Society of Agricultural Engineering,2000,16(6): 38-42. (in Chinese)
[35] 張學(xué)軍,吳政文,丁小明,李欣. 微噴帶水量分布特性試驗(yàn)分析.農(nóng)業(yè)工程學(xué)報(bào),2009,25(4): 66-69. ZHANG X J,WU Z W,DING X M,LI X. Experimental analysis of water distribution characteristics of micro-sprinkling hose. Transactions of the Chinese Society of Agricultural Engineering,2009,25(4): 66-69. (in Chinese)
[36] 王克鵬,張仁陟,董博,謝軍紅. 長(zhǎng)期保護(hù)性耕作對(duì)黃土高原旱地土壤水分及作物葉水勢(shì)的影響. 生態(tài)學(xué)報(bào),2014,34(13): 3752-3761. WANG K P,ZHANG R Z,DONG B,XIE J H. Effect of long- term conservation tillage on soil water regimes and leaf water potential of crops in rainfed areas of the Loess Plateau. Acta Ecologica Sinica,2014,34(13): 3752-3761. (in Chinese)
[37] 高鷺,胡春勝,陳素英. 噴灌條件下不同灌水處理冬小麥的葉水勢(shì)特征. 土壤,2005,37(4): 410-414. GAO L,HU C S,CHEN S Y. Characteristics of leaf water potential of winter wheat with different water treatments under sprinkling irrigation. Soils,2005,37(4): 410-414. (in Chinese)
[38] 張喜英,裴冬,由懋正. 幾種作物的生理指標(biāo)對(duì)土壤水分變動(dòng)的閾值反應(yīng). 植物生態(tài)學(xué)報(bào),2000,24(3): 280-283. ZHANG X Y,PEI D,YOU M Z. Response of leaf water potential,photosynthetic and stomatal conductance to varying soil moisture in four crops: winter wheat,corn,sorghum and millet. Acta Phytoecologica Sinica,2000,24(3): 280-283. (in Chinese)
[39] XUE Q W,ZHU Z X,MUSICK J T,STEWART B A,DUSEK D A. Physiological mechanisms contributing to the increased water use efficiency in winter wheat under deficit irrigation. Journal of Plant Physiology,2006,163: 154-164.
[40] 張雅倩,林琪,張玉梅,李玲燕,劉義國(guó). 干旱脅迫對(duì)不同小麥品種花后旗葉生理特性的影響. 干旱地區(qū)農(nóng)業(yè)研究,2010,28(6): 158-164. ZHANG Y Q,LIN Q,ZHANG Y M,LI L Y,LIU Y G. Effect of drought stress on physiological characteristics in flag leaf of different wheat cultivars after anthesis. Agricultural Research in the Arid Areas,2010,28(6): 158-164. (in Chinese)
[41] 張永平,張英華,王志敏. 不同供水條件下冬小麥葉與非葉綠色器官光合日變化特征. 生態(tài)學(xué)報(bào),2011,31(5): 1312-1322. ZHANG Y P,ZHANG Y H,WANG Z M. Photosynthetic diurnal variation characteristics of leaf and non-leaf organs in winter wheat under different irrigation regimes. Acta Ecologica Sinica,2011,31(5): 1312-1322. (in Chinese)
[42] 張永平,王志敏,王璞,趙明. 冬小麥節(jié)水高產(chǎn)栽培群體光合特征.中國(guó)農(nóng)業(yè)科學(xué),2003,36(10): 1143-1149. ZHANG Y P,WANG Z M,WANG P,ZHAO M. Canopy photosynthetic characteristics of population of winter wheat in water-saving and high-yielding cultivation. Scientia Agricultura Sinica,2003,36(10): 1143-1149. (in Chinese)
[43] 馬東輝,趙長(zhǎng)星,王月福,吳鋼,林琪. 施氮量和花后土壤含水量對(duì)小麥旗葉光合特性和產(chǎn)量的影響. 生態(tài)學(xué)報(bào),2008,28(10): 4896-4901. MA D H,ZHAO C X,WANG Y F,WU G,LIN Q. Effects of nitrogen fertilizer rate and post-anthesis soil water content on photosynthetic characteristics in flag leaves and yield of wheat. Acta Ecologica Sinica,2008,28(10): 4896-4901. (in Chinese)
(責(zé)任編輯 楊鑫浩,李莉)
Effects of Supplemental Irrigation with Micro-Sprinkling Hoses on Flag Leaves Senescence and Photosynthetic Characteristics,Grain Yield and Water Use Efficiency in Winter Wheat
XU Xue-xin1,2,WANG Dong1
(1College of Agronomy,Shandong Agricultural University/ State Key Laboratory of Crop Biology/Key Laboratory of Crop Ecophysiology and Farming System,Ministry of Agriculture,Taian 271018,Shandong;2College of Agronomy,China Agriculture University,Beijing 100193)
【Objective】The objective of the experiment is to study the effects of supplemental irrigation with micro-sprinkling hoses on flag leaves senescence,photosynthetic rate,grain filling rate,grain yield and water use efficiency in winter wheat. 【Method】 Field experiments were carried out in 2011-2013 growth seasons,using high-yield wheat cultivar Jimai 22. Three irrigation treatments were arranged with no irrigation during the whole growth stage (W0),supplemental irrigation with micro-sprinkling hoses (W1),traditional border irrigation (W2),to explore the changes of winter wheat under different treatments in leaf water potential,activities of superoxide dismutase (SOD) and catalase (CAT),chlorophyll fluorescence parameters,canopy apparent photosynthetic rate,grain filling rate,and so on. The irrigation stage in W1 was the same as that in W2. they were all irrigated once at jointing stage and anthesis stage respectively. W1 was irrigated with the micro-sprinkling hoses special for wheat (ZL201220356553.7). The soil water content was measured before irrigation. The target relative soil moisture content in the 0-140 cm soil layer after supplemental irrigation at jointing was set as 70% of field water capacity in 2011-2012 and 2012-2013. The target relative soil moisture content in the 0-140 cm soil layer after supplemental irrigation at anthesis was set as 70% and 65% of field water capacity in 2011-2012 and 2012-2013,respectively. The amount of the supplemental irrigation was calculated according to the irrigation quota formula. W2 was irrigated by the traditional border irrigation method. The inflow cutoff was set as 90% of border length,namely,stopping irrigation when the water reached 90% of the border length. The amount of irrigation was measured by water meter. W1 was the same as W2 in the specifications of experiment plot. In each experimental plot,the border width (the vertical distance between the center of two adjacent border ridges) was 2 m; the border ridge width was 0.4 m; the border length was 60 m and the plot area was 120 m2. A 1.0 m wide unirrigated zone was maintained between adjacent plots to minimize the effects of adjacent treatments. Eight rows of winter wheat were planted in each experimental plot with row spacing of 22.9 cm. The micro-sprinkling hose was laid between the fourth and the fifth rows of wheat. A pressure-regulated valve and a flow-meter were installed at the head of each micro-sprinkling irrigation hose. The working pressure of each micro-sprinkling irrigation hose was 0.02 MPa. The irrigation water was pumped from well and then was transported to the inlet of micro-sprinkling irrigation hose or border through the PVC belt. The discharge per unit width of border irrigation was 4.6-5.2 L·m-1·s-1.【Result】During the two growth seasons,the supplemental irrigation amounts of W1 were 21.3-96.0 mm at jointing and 29.0-38.5 mm at anthesis. The irrigation water distribution uniformity of W1 reached 82.7%-97.0% after irrigation,not lower than that of the border irrigation with inflow cutoff designed as 90% (W2). The total irrigation amount of W1 reduced by 33.2-70.8 mm,saving 21.0%-54.2% of irrigation water,compared to that of W2. In contrast,there was no significant difference between W1 and W2 in the flag leaf water potential,the activities of SOD and CAT,the content of methane dicarboxylic aldehyde,the flag leaf maximum photochemical efficiency,actual photochemical efficiency,canopy apparent photosynthetic rate,grain filling rate,and grain yield. The water use efficiency of W1 increased by 2.1-2.9 kg·hm-2·mm-1and reached 21.6-23.2 kg·hm-2·mm-1. 【Conclusion】 The irrigation amount applied at jointing and anthesis can be adjusted according to the precipitation and soil water content before irrigation by supplemental irrigation with micro-sprinkling hoses,to moderately supply the physiological water requirement of winter wheat for high-yield,and the irrigation water also can be uniformly and accurately sprayed into the field. This technology can excavate greater potential of winter wheat for water-saving.
common wheat; micro-sprinkling hoses; supplemental irrigation; border irrigation; flag leaf senescence; photosynthetic characteristics; yield; water use efficiency
2016-01-22;接受日期:2016-04-18
國(guó)家自然科學(xué)基金(31271660)、國(guó)家公益性行業(yè)(農(nóng)業(yè))科研專項(xiàng)(201503130)、山東省2014年度農(nóng)業(yè)重大應(yīng)用技術(shù)創(chuàng)新課題(2014-2016)
聯(lián)系方式:徐學(xué)欣,Tel:010-62732557;E-mail:xuxuexin2008@126.com。通信作者王東,Tel:0538-8242226;E-mail:wangd@sdau.edu.cn