光強(qiáng)和氮肥互作對(duì)南方軟米粳稻灌漿結(jié)實(shí)期碳氮代謝影響及其與產(chǎn)量品質(zhì)間關(guān)系

陳心怡 朱 盈 馬中濤 張明月 魏海燕 張洪程 劉國(guó)棟 胡 群 李光彥 許方甫

光強(qiáng)和氮肥互作對(duì)南方軟米粳稻灌漿結(jié)實(shí)期碳氮代謝影響及其與產(chǎn)量品質(zhì)間關(guān)系

陳心怡 朱 盈 馬中濤 張明月 魏海燕*張洪程 劉國(guó)棟 胡 群 李光彥 許方甫

揚(yáng)州大學(xué)江蘇省作物遺傳生理重點(diǎn)實(shí)驗(yàn)室 / 農(nóng)業(yè)農(nóng)村部長(zhǎng)江流域稻作技術(shù)創(chuàng)新中心 / 江蘇省糧食作物現(xiàn)代產(chǎn)業(yè)技術(shù)協(xié)同創(chuàng)新中心, 江蘇揚(yáng)州 225009

以南方軟米粳稻南粳9108和揚(yáng)農(nóng)香28為材料, 設(shè)置2個(gè)光強(qiáng)處理和4種氮肥處理, 其中光強(qiáng)處理于結(jié)實(shí)期展開(kāi), 分為100%自然光照強(qiáng)度(L1)和50%自然光照強(qiáng)度(L2), 氮肥處理為生長(zhǎng)中后期不施氮肥(N1), 分別于倒六葉(N2)、倒四葉(N3)、倒二葉(N4)期一次性施用氮肥, 研究了不同光照強(qiáng)度、氮肥施用時(shí)期及光氮互作條件下水稻結(jié)實(shí)期碳氮代謝差異及其對(duì)產(chǎn)量和品質(zhì)的影響。結(jié)果表明, 結(jié)實(shí)期光強(qiáng)減弱, 劍葉凈光合速率下降7.35%～42.36%、葉片中蔗糖磷酸合酶(SPS)和蔗糖合酶(SS)酶活性下降, 葉片C/N比下降3.98～6.49, 光合產(chǎn)物向籽粒輸送減少, 籽粒中淀粉(包括直鏈淀粉)含量降低, 同時(shí)葉片中硝酸還原酶(NR)、谷氨酰胺合酶(GS)、谷氨酸合酶(GOGAT)活性增強(qiáng), 植株含氮率提升, 蛋白質(zhì)含量相對(duì)增加, 不利于產(chǎn)量和優(yōu)良品質(zhì)的形成。中后期施用氮肥后, 葉片中碳氮代謝關(guān)鍵酶活性顯著提高、葉片的衰老減緩, 水稻的灌漿結(jié)實(shí)期延長(zhǎng), 有利于產(chǎn)量的提升。隨中后期氮肥施用時(shí)期推遲, 氮代謝愈發(fā)旺盛, 籽粒中蛋白質(zhì)含量相對(duì)明顯增加, 導(dǎo)致淀粉與蛋白質(zhì)、直鏈淀粉與蛋白質(zhì)的比值均下降, 食味值下降。本試驗(yàn)條件下, 正常光照配合倒四葉施用氮肥處理(L1～N3)能夠協(xié)同提高葉片碳氮代謝關(guān)鍵酶活性, 使得光合產(chǎn)物和含氮化合物以適宜的比例向籽粒輸送, 最終籽粒中淀粉與蛋白質(zhì)的比值在11.43～12.03之間, 直鏈淀粉與蛋白質(zhì)的比值在1.34～1.50之間, 米飯的硬度低, 黏度、平衡性高, 食味好, 可同時(shí)獲得高產(chǎn)和優(yōu)質(zhì)。

水稻; 光照; 氮肥; 碳氮代謝; 產(chǎn)量; 品質(zhì)

我國(guó)水稻的種植面積在3000萬(wàn)公頃左右, 其中粳稻種植面積占水稻種植總面積的24.3%, 且主要作為口糧供給, 對(duì)保障國(guó)家糧食安全具有重要作用。“秦嶺-淮河”以南的南方粳稻產(chǎn)區(qū)具有單產(chǎn)水平高、總產(chǎn)量大的特點(diǎn)。但與北方粳稻相比, 南方粳稻的稻米品質(zhì)尤其是食味品質(zhì)有待提高。近年來(lái), 南方水稻育種家為了滿足人們對(duì)于米飯“吃得好”的需求, 培育出了一批直鏈淀粉含量較低、食味較好的優(yōu)質(zhì)軟米粳稻品種。

水稻籽粒胚乳淀粉和蛋白質(zhì)合成和積累是影響水稻產(chǎn)量和品質(zhì)形成的重要因素[1], 其含量高低、結(jié)構(gòu)比例和分布狀態(tài)都與植株體內(nèi)的碳氮代謝過(guò)程密切相關(guān)[2-6]。水稻的碳氮代謝不僅取決于品種自身特性, 還受氮肥、光照等環(huán)境的影響。氮是水稻需求量最大的礦質(zhì)元素, 也是植物體內(nèi)許多化合物的重要組分。合理的N素有利于促進(jìn)地下部根系和地上部器官的協(xié)同生長(zhǎng)[7], 構(gòu)建良好的植株形態(tài), 影響葉片中葉綠體的結(jié)構(gòu), 提高植株光合作用強(qiáng)度, 增加穎花量[8-9], 延長(zhǎng)同化物生產(chǎn)持續(xù)期, 促進(jìn)植株對(duì)碳氮的同化和吸收能力。呂騰飛等[8]、呂川根等[10]、孫永健等[11]、從夕漢等[12]研究發(fā)現(xiàn), 增施氮肥以及適當(dāng)?shù)牡屎笠? 能夠增強(qiáng)水稻生長(zhǎng)過(guò)程中的碳氮代謝能力, 協(xié)調(diào)蔗糖磷酸合酶(SPS, EC 2.4.1.14)、蔗糖合酶(SS, EC 2.4.1.13)、硝酸還原酶(NR, EC 1.7.99.4)、谷氨酰胺合酶(GS, EC 6.3.1.2)等碳氮代謝相關(guān)酶之間的活性, 進(jìn)而促進(jìn)植株對(duì)碳氮的同化和吸收能力, 實(shí)現(xiàn)水稻產(chǎn)量和氮肥利用率的同步提高。氮肥施用在影響植株碳氮代謝的同時(shí)還會(huì)改變籽粒淀粉和蛋白質(zhì)的比例, 引起蛋白質(zhì)含量增加而降低稻米的食味品質(zhì)[13-14]。光照是影響水稻光合作用和生長(zhǎng)發(fā)育的重要因素[15-16]。一般認(rèn)為, 光強(qiáng)減弱會(huì)導(dǎo)致水稻產(chǎn)量降低, 且不同時(shí)期光強(qiáng)減弱對(duì)水稻產(chǎn)量的影響存在差異[17-19], 姜楠[20]認(rèn)為抽穗后弱光對(duì)水稻產(chǎn)量影響最大。同時(shí), 植株體內(nèi)碳氮代謝也會(huì)因?yàn)楣鈴?qiáng)減弱而變化。遮光后, 葉片中1,5-二磷酸核酮糖羧化酶/加氧酶(Rubisco, EC 4.1.1.39)活性及葉片中葉綠素/值下降[21-22], 葉片衰老速度減緩, 葉綠素含量增加, 光合速率下降, 碳代謝能力減弱。此外, 水稻的根系活力及根干重受遮光影響顯著降低, 氮素吸收能力下降[23], 但遮光條件下的光以藍(lán)紫光為主, 促進(jìn)含氮化合物的合成, 提高植株含氮量, 增強(qiáng)植株的氮同化能力[24-27]。盡管前人關(guān)于水稻碳氮代謝已有一定研究, 但主要集中在環(huán)境因素對(duì)常規(guī)水稻碳氮代謝的影響或水稻產(chǎn)量和氮肥吸收利用對(duì)碳代謝或氮代謝單要素的響應(yīng)上。而關(guān)于碳氮代謝對(duì)南方優(yōu)質(zhì)食味水稻的新類(lèi)型—軟米水稻產(chǎn)量、品質(zhì)綜合影響的研究尚有所缺乏, 為此, 本研究以?xún)?yōu)質(zhì)食味軟米粳稻南粳9108和揚(yáng)農(nóng)香28為材料, 設(shè)置中后期不同時(shí)期施用氮肥、結(jié)實(shí)期不同光強(qiáng)處理, 研究不同光、氮及光氮互作條件下南方軟米粳稻結(jié)實(shí)期碳氮代謝差異及其這種差異對(duì)軟米粳稻產(chǎn)量和品質(zhì)的影響, 以期為南方軟米粳稻優(yōu)質(zhì)豐產(chǎn)栽培提供一定的理論依據(jù)。

1 材料與方法

1.1 試驗(yàn)地點(diǎn)及供試材料

試驗(yàn)于2019—2020年在揚(yáng)州大學(xué)試驗(yàn)農(nóng)場(chǎng)(32°39′N(xiāo), 119°42′E)進(jìn)行, 土壤類(lèi)型為沙壤土, 地力較為良好, 土壤0～20 cm耕層有機(jī)質(zhì)含量為28.3 g kg–1、堿解氮177.6 mg kg–1、速效磷52.8 mg kg–1、速效鉀202 mg kg–1。供試品種為優(yōu)質(zhì)食味軟米粳稻南粳9108和揚(yáng)農(nóng)香28, 均屬遲熟中粳軟米粳稻品種。

1.2 試驗(yàn)設(shè)計(jì)

本研究采用裂區(qū)設(shè)計(jì), 品種為主區(qū), 結(jié)實(shí)期光照強(qiáng)度和氮素水平為裂區(qū)。如表1所示, 結(jié)實(shí)期光照強(qiáng)度設(shè)置2個(gè)處理: 100%自然光照強(qiáng)度(L1)和50%自然光照強(qiáng)度(L2), 其中, L2處理采用透光率為50%的黑色遮陽(yáng)網(wǎng)在水稻抽穗至成熟期進(jìn)行遮光處理。光強(qiáng)處理用照度計(jì)(LI-250型; LI-COR, 美國(guó))于08:00、12:00和16:00測(cè)量其網(wǎng)下透射率分別為52%、48%和51%, 平均50%。試驗(yàn)各小區(qū)基蘗肥用量一致,基肥、分蘗肥各施純氮94.5 kg hm–2, 中后期設(shè)置4種氮肥處理: 不施氮肥(N1), 分別為于倒六葉(N2)、倒四葉(N3)、倒二葉(N4)一次性施用氮肥, 其中氮肥用量為純氮81 kg hm–2, 每處理重復(fù)2次, 小區(qū)面積30 m2。氮(N)∶磷(P5O2)∶鉀(K2O)比例為2∶1∶2, 磷肥一次性基施, 鉀肥分別于耕翻前、拔節(jié)期等量施入。氮肥來(lái)源為尿素(N含量為46%), 磷肥來(lái)源為過(guò)磷酸鈣(P2O5含量為12%), 鉀肥來(lái)源為氯化鉀(K2O含量為60%)。每個(gè)氮肥處理大區(qū)之間筑35～40 cm土埂并用塑料薄膜包埂, 單獨(dú)排灌。水分管理及病蟲(chóng)草害防治等相關(guān)的栽培措施均按照優(yōu)質(zhì)高產(chǎn)栽培要求實(shí)施。其中, 2019年和2020年試驗(yàn)分別于5月25日和5月22日播種。

所用育秧盤(pán)為毯苗機(jī)插專(zhuān)用硬盤(pán), 育秧期間肥水管理遵循旱育秧原則, 2年分別于6月13日和6月15日人工模擬毯苗插秧機(jī)移栽, 秧齡分別為19 d和24 d, 栽插行株距為30 cm × 12 cm, 每穴4株苗。

表1 不同光強(qiáng)處理下氮肥用量

1.2 測(cè)定內(nèi)容與方法

1.2.1 葉片光合特性的測(cè)定 自開(kāi)花至花后42 d,每隔7 d選取標(biāo)記的同日開(kāi)花的植株, 使用LI- 6400XT 便攜式光合儀測(cè)定劍葉的凈光合速率, 測(cè)定時(shí)各處理均選取劍葉的相同位置。

1.2.2 葉面積指數(shù) 分別于拔節(jié)期、抽穗期和成熟期, 根據(jù)各小區(qū)的每穴平均莖蘗數(shù)取具有代表性的植株3穴, 測(cè)定植株綠葉面積, 進(jìn)而計(jì)算出葉面積指數(shù)。

1.2.3 碳、氮代謝相關(guān)酶活性 自開(kāi)花至花后42 d, 每隔7 d取標(biāo)記葉片液氮中速凍后置于–70℃超低溫冰箱中保存。蔗糖成酶、蔗糖磷酸合酶、硝酸還原酶、谷氨酰胺合酶、谷氨酸合酶活性的測(cè)定使用上海酶聯(lián)生物科技有限公司提供的相關(guān)試劑盒并按照相應(yīng)方法進(jìn)行測(cè)定。

1.2.4 可溶性糖及淀粉含量 自開(kāi)花至花后42 d,每隔7 d取標(biāo)記植株的葉片和籽粒105℃殺青0.5 h, 80℃烘干至恒重后粉碎并過(guò)100目篩, 稱(chēng)取0.1 g樣品至10 mL離心管, 加入8 mL配制的80%乙醇溶液80℃水浴30 min, 冷卻后離心, 重復(fù)3次, 合并上清液用于測(cè)定可溶性糖, 殘?jiān)糜跍y(cè)定淀粉, 采用蒽酮比色法測(cè)定可溶性糖和淀粉含量[28]。

1.2.5 高效葉片SPAD值的測(cè)定 高效葉片指水稻植株有效莖蘗抽穗后上3張葉片。自開(kāi)花至花后42 d, 每隔7 d選取標(biāo)記的同日開(kāi)花的植株, 采用葉綠素儀SPAD-502儀(日本柯尼卡美能公司)測(cè)定標(biāo)記植株高效葉片的SPAD值, 取其平均值。

1.2.6 含氮率 自開(kāi)花至花后42 d, 每隔7 d選取標(biāo)記植株3穴, 將所取植株樣品于105℃殺青30 min, 80℃烘至恒重后測(cè)定干物質(zhì)重。樣品粉碎后采用H2SO4-H2O2消化, 半微量凱氏定氮法測(cè)定植株含氮率。

1.2.7 產(chǎn)量及其結(jié)構(gòu) 成熟期時(shí), 每小區(qū)隨機(jī)選取5個(gè)點(diǎn)(每點(diǎn)15穴), 調(diào)查有效穗數(shù), 按各小區(qū)每穴平均穗數(shù)取5穴以考查每穗粒數(shù)、結(jié)實(shí)率、千粒重(取1000粒稱(chēng)重, 重復(fù)3次, 誤差不超過(guò)0.05 g)。每小區(qū)割取100穴, 脫粒、去雜后晾曬至含水量14.5%時(shí)測(cè)定籽粒重量, 計(jì)算產(chǎn)量。

1.2.8 糙米直鏈淀粉、總淀粉含量 取標(biāo)記的同日開(kāi)花的稻穗, 穗上籽粒出糙后粉碎, 購(gòu)買(mǎi) Megazyme 試劑盒并參照相應(yīng)方法測(cè)定直鏈淀粉和總淀粉含量。

1.2.9 籽粒中蛋白質(zhì)含量 成熟期取標(biāo)記穗, 穗上籽粒出糙后粉碎, 籽粒中蛋白質(zhì)含量采用凱氏定氮法測(cè)定(Kjeltec 8200, Foss, Hillerod, 丹麥)。

1.2.10 稻米品質(zhì) 參照國(guó)家標(biāo)準(zhǔn)《GB/T17891- 1999優(yōu)質(zhì)稻谷》和《GB/T17891-2017優(yōu)質(zhì)稻谷》方法, 測(cè)定出糙率、出精率、整精米率、堊白粒率、堊白大小、堊白度。采用米飯食味計(jì)(STA1A, 日本佐竹公司)測(cè)定米飯的食味參數(shù)。

1.3 數(shù)據(jù)計(jì)算與統(tǒng)計(jì)分析

葉面積衰減率=葉面積衰減率(LAI d–1)= (LAI2–LAI1)/(t2–t1), 式中, LAI1和LAI2分別為抽穗期和成熟期測(cè)定的葉面積指數(shù), t1和t2分別為抽穗期和成熟期測(cè)定的時(shí)間; C/N[29]=可用性糖的積累量(可溶性總糖+淀粉)/氮素的積累量; 氮素積累量(kg hm–2)=干物質(zhì)積累量×含氮率。

用Microsoft Excel 2016進(jìn)行數(shù)據(jù)的錄入和計(jì)算,運(yùn)用SPSS軟件進(jìn)行統(tǒng)計(jì)分析, 用新復(fù)極差法SSR進(jìn)行多重比較(<0.05), 產(chǎn)量及品質(zhì)2年結(jié)果趨勢(shì)一致, 年度間差異未達(dá)顯著水平, 取2年平均值進(jìn)行分析, 其余對(duì)測(cè)定年度數(shù)據(jù)進(jìn)行分析; 以O(shè)rigin 2018軟件作圖。

2 結(jié)果與分析

2.1 不同光、氮條件下南方優(yōu)質(zhì)粳稻碳代謝的差異

2.1.1 劍葉凈光合速率 50%光強(qiáng)處理下水稻花后劍葉的凈光合速率顯著降低, 供試2個(gè)品種的變化基本一致, 降幅在7.35%～42.36% (表2)。中后期施用氮肥后, 花后2個(gè)軟米粳稻品種的凈光合速率顯著提高, 并且升幅在正常光照強(qiáng)度處理下會(huì)隨著中后期氮肥施用時(shí)期的推遲逐漸增加, 與N1處理相比, N2、N3、N4分別增加了2.90%～7.96%、5.61%～ 14.37%、8.84%～25.09%, 而在50%光強(qiáng)處理下升幅則隨著中后期氮肥施用時(shí)期的推遲逐漸減少。2種光強(qiáng)處理下, 2個(gè)品種的凈光合速率均以L1N4處理最高。除開(kāi)花期外, 光強(qiáng)、氮素及其互作效應(yīng)對(duì)劍葉凈光合速率的影響均達(dá)到了顯著水平。

表2 不同光、氮條件下南方軟米粳稻花后劍葉凈光合速率的差異

(續(xù)表2)

標(biāo)以不同小寫(xiě)字母的值分別表示同一品種不同處理在0.05概率水平差異顯著。*和**分別表示在0.05和0.01概率水平差異顯著。

Different lowercase letters indicate that there are significant difference in the 0.05 probability level in different treatments of the same variety.*and**indicate significant differences at the 0.05 and 0.01 probability levels, respectively.

2.1.2 葉面積指數(shù)及葉面積衰減率 50%光強(qiáng)處理下水稻拔節(jié)期和抽穗期的葉面積指數(shù)在處理間差異不顯著(表3), 成熟期葉面積指數(shù)顯著提高, 供試2個(gè)品種的變化基本一致, 升幅在7.89%～29.98%。中后期施用氮肥后, 2個(gè)品種葉面積指數(shù)顯著提高, 結(jié)實(shí)期葉面積衰減率降低。隨著中后期氮肥施用時(shí)期的推遲, 2個(gè)品種拔節(jié)期葉面積指數(shù)逐漸下降, 抽穗期葉面積指數(shù)先增后減, 并以N3處理最大, 成熟期葉面積指數(shù)在不同光強(qiáng)處理下表現(xiàn)不一致, 在正常光強(qiáng)處理表現(xiàn)為先升后降, 在50%光強(qiáng)處理下則逐漸下降。2個(gè)品種結(jié)實(shí)期葉面積衰減率在正常光強(qiáng)處理下隨中后期氮肥施用時(shí)期的推遲逐漸降低, 在50%光強(qiáng)處理下表現(xiàn)為先增后減。

表3 不同光、氮條件下南方軟米粳稻葉面積指數(shù)及葉面積衰減率的差異

標(biāo)以不同小寫(xiě)字母的值分別表示同一品種不同處理在0.05概率水平差異顯著。*和**分別表示在0.05和0.01概率水平差異顯著, NS表示差異不顯著。

Different lowercase letters indicate that there are significant difference in the 0.05 probability level in different treatments of the same variety.*and**indicate significant differences at the 0.05 and 0.01 probability levels, respectively, and NS indicates no significant differences.

圖1 不同光強(qiáng)、氮肥條件下南方軟米粳稻花后葉片中蔗糖合酶(SS)、蔗糖磷酸合酶(SPS)的差異

圖中“L1, L2”分別指結(jié)實(shí)期100%自然光照強(qiáng)度和50%自然光照強(qiáng)度, “N2, N3, N4”分別指中后期于倒六葉, 倒四葉, 倒二葉施用氮肥, “N1”指中后期不施氮肥處理。圖中所標(biāo)注的字母為蔗糖合酶和蔗糖磷酸合酶活性的顯著性, 不同字母表示在0.05概率水平差異顯著。

“L1, L2” in the figure refer to 100% natural light intensity and 50% natural light intensity at grain-filling stage, respectively. “N2, N3, and N4” refer to applying nitrogen fertilizer to 6 leaves, 4 leaves, and 2 leaves at middle and late stage, respectively. “N1” refers to not applying nitrogen fertilizer at middle and late stage. Different lowercase letters indicate significantly different at the 0.05 probability level for the activity of sucrose synthetase and sucrose phosphate synthetase.

2.1.3 碳代謝相關(guān)酶 50%光強(qiáng)處理下供試2個(gè)品種葉片中碳代謝相關(guān)的蔗糖合酶(SS)、蔗糖磷酸合酶(SPS)的活性均顯著降低(圖2)。中后期施用氮肥后, SS、SPS活性顯著增強(qiáng)。隨著中后期氮肥施用時(shí)期的推遲, SS、SPS的活性的升幅逐漸增加。光、氮共同處理下, 南粳9108和揚(yáng)農(nóng)香28葉片中SS、SPS活性均呈現(xiàn)L1N4>L1N3>L1N2>L1N1>L2N4> L2N3>L2N2>L2N1的趨勢(shì)。

圖2 不同光、氮條件下南方軟米粳稻花后葉片中可溶性糖和淀粉含量的差異

處理同圖1。圖中所標(biāo)注字母為葉片淀粉和可溶性糖含量的顯著性, 不同字母表示在0.05概率水平差異顯著。

Treatments are the same as those given in Fig. 1. Different lowercase letters indicate significantly different at the 0.05 probability level in the content of soluble sugar and starch in leaves.

2.1.4 葉片可溶性糖和淀粉含量 50%光強(qiáng)處理下供試2個(gè)品種水稻葉片中可溶性糖和淀粉含量均顯著降低(圖3)。中后期施用氮肥后, 葉片中可溶性糖和淀粉含量顯著下降。隨著中后期施肥時(shí)間的推遲, 葉片中可溶性糖和淀粉含量的降幅逐漸增大, 與N1處理相比, N2、N3、N4可溶性糖含量分別降低了1.51%～7.97%、4.43%～13.25%、9.24%～21.69%, 淀粉含量分別降低2.85%～10.36%、4.28%～17.15%、5.44%～23.04%。光、氮共同處理下, 南粳9108和揚(yáng)農(nóng)香28花后7～42 d葉片中可溶性糖和淀粉含量均呈現(xiàn)L1N1>L1N2>L1N3>L1N4>L2N1>L2N2>L2N3> L2N4的趨勢(shì)。

2.1.5 籽粒可溶性糖和淀粉含量 50%光強(qiáng)處理下供試2個(gè)品種水稻籽粒中可溶性糖和淀粉含量均顯著降低(圖4)。中后期施用氮肥后, 籽粒中可溶性糖和淀粉含量均顯著下降。隨著中后期施肥時(shí)間的推遲, 籽粒中可溶性糖和淀粉含量的降幅逐漸增大, 與N1處理相比, N2、N3、N4可溶性糖含量分別降低了1.23%～9.64%、3.44%～13.47%、4.13%～18.81%, 淀粉含量分別降低了1.40%～7.18%、1.73%～12.30%、3.44%～16.92%。光、氮共同處理下, 南粳9108和揚(yáng)農(nóng)香28花后7～42 d籽粒中可溶性糖和淀粉含量均呈現(xiàn)L1N1>L1N2>L1N3>L1N4>L2N1>L2N2>L2N3> L2N4的趨勢(shì)。

2.2 不同光、氮條件下南方優(yōu)質(zhì)粳稻氮代謝的差異

2.2.1 花后高效葉片SPAD值 50%光強(qiáng)處理下水稻花后高效葉片的SPAD值顯著升高(表4), 供試2個(gè)品種的變化基本一致, 升幅在1.5%～69.0%, 且成熟期與開(kāi)花期的SPAD比值顯著增加。中后期施用氮肥后, 2個(gè)品種花后高效葉片的SPAD值顯著升高, 且升幅隨著中后期氮肥施用時(shí)期的推遲逐漸增加, 與N1處理相比, N2、N3、N4分別增加了5.44%～ 7.0%、8.48%～12.65%、12.73%～18.85%。2個(gè)品種SPAD值均呈現(xiàn)L2N4處理最高, 相較于L1N1處理增加了17.25%～90.45%。

2.2.2 花后葉片、植株含氮率及N素積累 50%光強(qiáng)處理下供試2個(gè)品種花后植株及葉片的含氮率均顯著升高(表5和表6); 中后期施用氮肥后, 植株及葉片的含氮率顯著上升, 隨中后期氮肥施用時(shí)期的推遲升幅逐漸增加, 與N1處理相比, N2、N3、N4處理植株含氮率分別增加了6.46%～9.25%、12.24%～ 19.59%、17.81%～30.33%, 葉片含氮率分別增加了6.45%～12.08%、9.83%～18.67%、16.04%～23.70%。此外, 50%光強(qiáng)處理下中后期施用氮肥對(duì)植株含N率的增加效應(yīng)更加顯著。2個(gè)品種花后植株及葉片的含氮率均以L2N4處理最高, 相較于L1N1處理, 植株含氮率增加了15.60%～73.40%, 葉片含氮率增加了24.53%～57.07%。抽穗至成熟期的氮素積累, 2個(gè)品種均在L1N3處理下積累量最高。光、氮及光氮互作對(duì)植株及葉片含氮率的影響在開(kāi)花期以后均達(dá)到極顯著水平, 對(duì)抽穗至成熟期的氮素積累的影響也達(dá)極顯著水平。

圖3 不同光、氮條件下南方軟米粳稻花后籽粒中可溶性糖和淀粉含量的差異

處理同圖1。圖中所標(biāo)注字母為籽粒淀粉和可溶性糖含量的顯著性, 不同字母表示在0.05概率水平差異顯著。

Treatments are the same as those given in Fig. 1. Different lowercase letters indicate significantly different at the 0.05 probability level for the content of soluble sugar and starch in grains.

圖4 不同光、氮條件下南方軟米粳稻花后葉片中硝酸還原酶(NR)、谷氨酰胺合酶(GS)和谷氨酸合酶(GOGAT)的差異

處理同圖1。圖中所標(biāo)注字母為硝酸還原酶、谷氨酰胺合酶和谷氨酸合酶的顯著性, 不同字母表示在0.05概率水平差異顯著。

Treatments are the same as those given in Fig. 1. Different lowercase letters indicate significantly different at the 0.05 probability level for activity of nitrate reductase, glutamine synthetase, and glutamate synthetase.

2.2.3 氮代謝相關(guān)酶 50%光強(qiáng)處理下供試2個(gè)品種葉片中氮代謝相關(guān)的硝酸還原酶(NR)、谷氨酰胺合酶(GS)、谷氨酸合酶(GOGAT) (EC 2.6.1.53)的活性均顯著增強(qiáng)(圖3)。中后期施用氮肥后, 2個(gè)品種葉片中NR、GS、GOGAT活性顯著增強(qiáng), 且隨著中后期氮肥施用時(shí)期的推遲增幅逐漸增加。在光、氮共同處理下, 南粳9108和揚(yáng)農(nóng)香28的NR、GS、GOGAT活性在灌漿后期均表現(xiàn)為L(zhǎng)2N4>L2N3> L2N2>L2N1>L1N4>L1N3>L1N2>L1N1。

2.2.4 葉片和籽粒的碳氮比 50%光強(qiáng)處理下水稻成熟期葉片和籽粒中的C/N均顯著降低(圖6), 供試2個(gè)品種的變化基本一致, 其中葉片中C/N下降40.43%～54.23%, 籽粒中C/N下降34.04%～38.16%。中后期施用氮肥后, 2個(gè)品種葉片和籽粒中的C/N下降, 下降幅度隨著中后期氮肥施用時(shí)期的推遲逐漸增加, 與N1處理相比, N2、N3、N4處理下葉片中C/N分別降低了7.69%～13.45%、14.15%～22.66%、20.81%～26.31%, 籽粒中C/N分別降低了4.03%～ 5.39%、7.80%～10.89%、12.50%～14.55%。

2.3 不同光、氮條件對(duì)優(yōu)質(zhì)粳稻產(chǎn)量的影響

2.3.1 產(chǎn)量及產(chǎn)量結(jié)構(gòu) 雖然50%光強(qiáng)處理下供試2個(gè)品種的每穗粒數(shù)和總穎花量無(wú)顯著差異, 但結(jié)實(shí)率、千粒重顯著下降, 產(chǎn)量降低(表7)。中后期施用氮肥后, 2個(gè)品種總穎花量和產(chǎn)量顯著升高。隨著中后期氮肥施用時(shí)期的推遲, 總穎花量呈現(xiàn)N3>N2>N4的趨勢(shì), 結(jié)實(shí)率在正常光照強(qiáng)度處理下隨中后期氮肥施用時(shí)期的推遲逐漸上升, 產(chǎn)量則呈現(xiàn)先升后減的趨勢(shì), 而在50%光強(qiáng)處理下結(jié)實(shí)率和產(chǎn)量均隨著中后期氮肥施用時(shí)期的推遲逐漸下降。光、氮及光氮互作對(duì)2個(gè)品種產(chǎn)量的影響均達(dá)極顯著水平, 產(chǎn)量以L1N3處理最高, 遮光處理下, 產(chǎn)量隨著中后期氮肥施用時(shí)期的推遲而逐漸下降, 表明中后期適當(dāng)?shù)奶崆笆┯玫士删彍p光照不足導(dǎo)致的產(chǎn)量下降。光照強(qiáng)度對(duì)結(jié)實(shí)率和千粒重的影響達(dá)極顯著水平, 氮素對(duì)產(chǎn)量構(gòu)成因素均達(dá)極顯著水平。

圖5 不同光、氮條件下對(duì)南方軟米粳稻葉片和籽粒C/N比的差異

處理同圖1。圖中所標(biāo)注字母為葉片和籽粒中C/N的顯著性, 不同字母表示在0.05概率水平差異顯著。

Treatments are the same as those given in Fig. 1. Different lowercase letters indicate significantly different at the 0.05 probability level for C/N ratio of leaves and grains.

表7 不同光、氮條件下南方軟米粳稻產(chǎn)量構(gòu)成因素的差異

處理同圖1。標(biāo)以不同小寫(xiě)字母的值分別表示同一品種不同處理在0.05概率水平差異顯著。*和**分別表示在0.05和0.01概率水平差異顯著, NS表示差異不顯著。

Treatments are the same as those given in Fig. 1. Different lowercase letters indicate that there are significant difference in the 0.05 probabi-lity level in different treatments of the same variety.*and**indicate significant differences at the 0.05 and 0.01 probability levels, respectively, and NS indicates no significant differences.

2.3.2 干物質(zhì)積累 50%光強(qiáng)處理下供試2個(gè)品種抽穗期干物質(zhì)積累無(wú)顯著差異(表8), 成熟期及花后干物質(zhì)積累量顯著降低。中后期施用氮肥后, 抽穗期、成熟期及花后干物質(zhì)的積累量均顯著提高, 且隨著中后期肥施用時(shí)期的推遲, 抽穗期的干物質(zhì)積累量先增后減, 成熟期及花后干物質(zhì)積累量在正常光照強(qiáng)度處理下隨中后期氮肥施用時(shí)期的推遲先增后減, 而在50%光強(qiáng)處理下則逐漸減少。光、氮及光氮互作對(duì)2個(gè)品種抽穗期、成熟期及花后干物質(zhì)的積累量的影響均達(dá)極顯著水平。

2.4 不同光照、氮素條件對(duì)優(yōu)質(zhì)粳稻品質(zhì)的影響

2.4.1 加工和外觀品質(zhì) 50%光強(qiáng)處理下水稻的糙米率、精米率、整精米率均顯著降低(表9), 2個(gè)供試品種的變化基本一致, 降幅在2.08%～11.51%, 堊白粒率和堊白度均顯著升高; 在中后期施用氮肥后, 糙米率、精米率、整精米率、堊白粒率和堊白度均顯著升高, 且升幅隨中后期氮肥施用時(shí)期的推遲逐漸增加; 在50%光強(qiáng)處理下中后期推遲施用氮肥, 能夠緩解由于光照強(qiáng)度不足造成的糙米率、精米率、整精米率下降, 但同時(shí)增加了籽粒堊白粒率和堊白度。

表8 不同光、氮條件下南方軟米粳稻干物質(zhì)積累的差異

處理同圖1。標(biāo)以不同小寫(xiě)字母的值分別表示同一品種不同處理在0.05概率水平差異顯著。*和**分別表示在0.05和0.01概率水平差異顯著, NS表示差異不顯著。

Treatments are the same as those given in Fig. 1. Different lowercase letters indicate that there are significant difference in the 0.05 probabi-lity level in different treatments of the same variety.*and**indicate significant differences at the 0.05 and 0.01 probability levels, respectively, and NS indicates no significant differences.

表9 不同光、氮條件對(duì)南方軟米粳稻加工和外觀品質(zhì)的差異

(續(xù)表9)

處理同圖1。標(biāo)以不同小寫(xiě)字母的值分別表示同一品種不同處理在0.05概率水平差異顯著。*和**分別表示在0.05和0.01概率水平差異顯著, NS表示差異不顯著。

Treatments are the same as those given in Fig. 1. Different lowercase letters indicate that there are significant difference in the 0.05 probabi-lity level in different treatments of the same variety.*and**indicate significant differences at the 0.05 and 0.01 probability levels, respectively, and NS indicates no significant differences.

2.4.2 營(yíng)養(yǎng)和蒸煮食味品質(zhì) 50%光強(qiáng)處理下供試2個(gè)品種的蛋白質(zhì)含量(PC)均顯著提高(表10), 總淀粉含量(TSC)、直鏈淀粉含量(AC)及AC/PC、TSC/PC均顯著降低。中后期施用氮肥后, 2個(gè)品種的蛋白質(zhì)含量顯著提高, 總淀粉含量、直鏈淀粉含量、AC/PC及TSC/PC均顯著下降, 隨著中后期氮肥施用時(shí)期的推遲, 蛋白質(zhì)含量的升幅、總淀粉含量、直鏈淀粉含量的降幅逐漸增加, AC/PC、TSC/PC逐漸降低。50%光強(qiáng)處理下中后期推遲施用氮肥與正常光照強(qiáng)度處理下相一致, 2個(gè)品種的蛋白質(zhì)含量顯著提高、總淀粉含量、直鏈淀粉含量、AC/PC及TSC/PC顯著下降。

50%光強(qiáng)處理下供試2個(gè)品種的硬度較高, 但外觀、黏度、平衡度以及食味值均較低。中后期施用氮肥后, 2個(gè)品種的硬度增加, 外觀、黏度、平衡度以及食味值降低, 且隨著中后期氮肥施用時(shí)期的推遲, 除硬度呈遞增趨勢(shì)外, 其余指標(biāo)逐漸遞減。在光、氮共同作用下, 食味值在L1N1處理下最優(yōu), 此時(shí)2個(gè)品種籽粒中AC/PC、TSC/PC均最高。

3 討論

3.1 碳氮代謝對(duì)水稻產(chǎn)量的影響

光照強(qiáng)度影響水稻碳氮代謝進(jìn)而影響產(chǎn)量。本研究中結(jié)實(shí)期遮光, 光強(qiáng)僅為自然光的50%, 水稻花后劍葉凈光合速率下降7.35%～42.36%、同時(shí)葉片中蔗糖磷酸合酶(SPS)和蔗糖合酶(SS)酶活性下降, 碳代謝能力減弱, 不利于葉片中可溶性糖及淀粉合成, 導(dǎo)致葉片C/N比下降3.98～6.49, 水稻花后干物質(zhì)生產(chǎn)能力大幅降低。水稻碳代謝減弱, 無(wú)法為葉片等營(yíng)養(yǎng)器官中的氮素同化為氨基酸和蛋白質(zhì)并向籽粒中轉(zhuǎn)運(yùn)的過(guò)程提供足夠的碳骨架, 導(dǎo)致氮素在水稻各器官中的分配比例改變[30-31], 更多的氮素滯留于葉片[26,32], 來(lái)維持葉片中較高的硝酸還原酶(NR)、谷氨酰胺合酶(GS)、谷氨酸合酶(GOGAT)活性同時(shí)讓葉片長(zhǎng)期持綠[33-34], 保持較高的SPAD值, 以致于水稻貪青遲熟[18,30], 籽粒灌漿不充分, 籽粒C/N比下降17.44～19.28, 結(jié)實(shí)率和千粒重顯著降低[35], 產(chǎn)量下降。

氮素在調(diào)節(jié)植株氮代謝的同時(shí)也在間接影響水稻碳代謝, 進(jìn)而共同影響水稻產(chǎn)量。中后期施用氮肥能夠促進(jìn)根系的生長(zhǎng)發(fā)育, 維持根系活力[36], 加快氮素吸收, 從而提升地上部植株及葉片的氮素含量。氮素能調(diào)控葉綠素合成與分解, 充足的氮素會(huì)減緩葉綠素等光合色素的分解[37], 延緩葉片的衰老, 延長(zhǎng)水稻的灌漿結(jié)實(shí)期。同時(shí)中后期氮肥的施用使得植株綠葉面積增大、葉片中NR、GS、GOGAT酶活性增強(qiáng), 同時(shí)葉片保持較高的SPAD值, 在正常光照條件下, 葉片的光合生產(chǎn)效率提升[38-40], 葉片中SPS、SS酶活性也隨之增強(qiáng)。水稻分蘗的生長(zhǎng)受碳氮代謝的直接影響, 碳代謝增強(qiáng), 更多的糖類(lèi)經(jīng)韌皮部轉(zhuǎn)運(yùn)到分蘗芽中積累, 促進(jìn)分蘗生長(zhǎng)[38,41-42]。因此水稻群體在中后期施用氮肥后群體穎花量增加, 抽穗后光合生產(chǎn)持續(xù)穩(wěn)定在較高水平, 加以灌漿結(jié)實(shí)期延長(zhǎng), 有更多的氮素和光合產(chǎn)物向穗部源源不斷地輸送[43-44], 籽粒灌漿充分[45], 產(chǎn)量增加。本研究中隨著中后期施肥時(shí)期的推遲, 抽穗后劍葉凈光合速率、葉綠素含量及碳氮代謝關(guān)鍵酶活性均逐漸升高, N3 (倒四葉施用氮肥)處理下, 葉片碳代謝能力增強(qiáng), 促進(jìn)穎花分化, 形成大穗, 拉動(dòng)植株對(duì)氮素的吸收, 從而形成高產(chǎn)。

50%光強(qiáng)條件下中后期施用氮肥, 使得原本相對(duì)較高的氮代謝因?yàn)槭┯昧说识油? 葉片C/N比進(jìn)一步降低, 氮素在葉片中大量積累, 直至成熟期, 葉色因氮含量高而保持濃綠, 成熟期葉片與抽穗期葉片的SPAD比值相較于正常光照強(qiáng)度上升了0.16～0.17, 葉片中充足的氮素營(yíng)養(yǎng)因缺少光照條件而不能充分用于促進(jìn)光合產(chǎn)物的生產(chǎn)并向籽粒的輸送而滯留于葉片, 難以實(shí)現(xiàn)結(jié)實(shí)階段碳氮代謝平衡而獲得高產(chǎn)。

3.2 碳氮代謝對(duì)水稻品質(zhì)的影響

水稻源器官生產(chǎn)的光合同化物以蔗糖的形式經(jīng)韌皮部運(yùn)輸?shù)阶蚜５倪^(guò)程中也伴隨著植株體內(nèi)包括功能葉片中的氮素轉(zhuǎn)化為氨基酸向籽粒的協(xié)同輸送,最終在籽粒中形成一定比例的碳氮代謝產(chǎn)物——淀粉和蛋白質(zhì), 從而決定稻米的品質(zhì)[46-50]。50%光強(qiáng)條件下, 水稻葉片的凈光合速率下降, 葉片中的光合產(chǎn)物減少, 同化物分配發(fā)生紊亂, 胚乳淀粉合成受限, 籽粒中淀粉含量和直鏈淀粉含量均降低[51], 淀粉體排列疏松, 間隙增大, 籽粒的堊白率和堊白度增加[24,51-52]。光強(qiáng)減弱后碳代謝的減弱伴隨著氮代謝的相對(duì)增強(qiáng), 本研究中遮光后光強(qiáng)僅為自然光強(qiáng)的50%, 且可利用光是以藍(lán)紫光為主的散射光。藍(lán)紫光能促進(jìn)氮素的合成, 導(dǎo)致植株含氮量增加[32], 進(jìn)而促進(jìn)蛋白質(zhì)的積累, 使得成熟期籽粒蛋白質(zhì)含量上升, C/N比下降。過(guò)多的蛋白質(zhì)與直鏈淀粉形成復(fù)合物, 增加了淀粉粒的剛性, 阻止大米在糊化過(guò)程中淀粉粒的膨脹和崩解, 促進(jìn)淀粉回生, 最終導(dǎo)致米飯硬度增加, 黏度、平衡性降低, 食味品質(zhì)變差[53-54]。

氮素在調(diào)節(jié)碳氮代謝的同時(shí)也調(diào)控稻米品質(zhì)。中后期施用氮肥后, 葉片中氮代謝相較于碳代謝更加旺盛, 花后更多的含氮化合物轉(zhuǎn)運(yùn)至籽粒中, 籽粒C/N下降, 蛋白質(zhì)含量相對(duì)增加[55]。蛋白質(zhì)含量增加后更好的填充了因?yàn)榈矸鄢鋵?shí)不完整而造成的空隙[56], 胚乳結(jié)構(gòu)愈加堅(jiān)硬緊致, 抗壓性增強(qiáng), 加工和外觀品質(zhì)得到改善, 同時(shí)蛋白質(zhì)含量增加, 限制稻米蒸煮過(guò)程中的吸水, 食味品質(zhì)變差。隨著中后期氮肥施用時(shí)期的推遲, 籽粒C/N進(jìn)一步下降, 蛋白質(zhì)和淀粉的比例發(fā)生改變, 籽粒中蛋白質(zhì)含量更高, 淀粉和直鏈淀粉含量則下降趨勢(shì)。碳氮代謝強(qiáng)度與碳氮代謝產(chǎn)物的積累密切相關(guān)[57], 適宜的碳氮代謝產(chǎn)物比例有助于形成良好的食味品質(zhì), 本研究中N2處理在中后期施用氮肥處理中籽粒C/N、淀粉/蛋白質(zhì)及直鏈淀粉/蛋白質(zhì)的比值最高, 食味品質(zhì)最優(yōu)。

50%光強(qiáng)條件下中后期施用氮肥, 碳代謝減弱的同時(shí)氮代謝相對(duì)旺盛, 籽粒中C/N進(jìn)一步下降, 淀粉與蛋白質(zhì)、直鏈淀粉與蛋白質(zhì)的比值分別在7.87～9.93和0.80～1.20之間, 同正常光強(qiáng)條件施用氮肥相比分別下降了2.28～3.51、0.35～0.49, 米飯的硬度增加, 黏度、平衡性降低, 食味值降低[53]。

4 結(jié)論

水稻結(jié)實(shí)期平衡的碳氮代謝是水稻獲得高產(chǎn)優(yōu)質(zhì)的基礎(chǔ)。光強(qiáng)減弱, 葉片凈光合速率和葉片中碳代謝相關(guān)酶活性下降, 不能為氮代謝的進(jìn)行提供充足的碳源和能量, 中后期適期施用氮肥能為水稻的生長(zhǎng)提供充足的氮素營(yíng)養(yǎng), 葉片延緩衰老, 葉片中氮代謝相關(guān)酶活性增強(qiáng), 在提升水稻氮代謝的同時(shí)又能夠進(jìn)一步提高水稻葉片的凈光合速率, 增強(qiáng)碳代謝能力, 促進(jìn)籽粒中碳氮代謝產(chǎn)物的積累。本試驗(yàn)條件下, 正常光照強(qiáng)度配合倒四葉施用氮肥處理(L1～N3)能夠協(xié)同提高葉片碳氮代謝關(guān)鍵酶活性, 使得光合產(chǎn)物和含氮化合物以適宜的比例向籽粒輸送, 最終籽粒中淀粉與蛋白質(zhì)的比值在11.55～11.95之間, 直鏈淀粉與蛋白質(zhì)的比值在1.37～1.47之間, 米飯的硬度低, 黏度、平衡性高, 食味好, 可同時(shí)獲得高產(chǎn)和優(yōu)質(zhì)。

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Effects of light intensity and nitrogen fertilizer interaction on carbon and nitrogen metabolism at grain-filling stage and its relationship with yield and quality of southern softrice

CHEN Xin-Yi, ZHU Ying, MA Zhong-Tao, ZHANG Ming-Yue, WEI Hai-Yan*, ZHANG Hong-Cheng, LIU Guo-Dong, HU Qun, LI Guang-Yan, and XU Fang-Fu

Jiangsu Key Laboratory of Crop Genetics and Physiology / Innovation Center of Rice Cultivation Technology in Yangtze Valley, Ministry of Agriculture / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, Jiangsu, China

Southern softrice Nanjing 9108 and Yangnongxiang 28 were selected as the experimental materials, and two light intensity treatments, and four nitrogen treatments were set. Light intensity treatments [100% natural light intensity (L1) and 50% natural light intensity (L2)] and four nitrogen treatments [no nitrogen fertilizer (N1) in the middle and late growth stages, one-time nitrogen fertilizer applied at the top sixth leaf stage (N2), one-time nitrogen fertilizer applied at the top fourth leaf stage (N3), and one-time nitrogen fertilizer applied at the top second leaf stage (N4)] were conducted at grain-filling stage. The difference of carbon and nitrogen metabolism at grain-filling stage and its effects on rice yield and quality under the conditions of different light intensity and nitrogen application period as well as light-nitrogen interaction conditions were investigated. The results showed that with the decrease of light intensity at grain-filling stage the net photosynthetic rate of flag leaf decreased by 7.35%–42.36% on average, sucrose phosphate synthase (SPS), and sucrose synthase (SS) had low activity, the C/N ratio of leaves decreased by 3.98–6.49, the transportation of photosynthetic products to grains decreased, and the content of grain starch (including amylose) decreased. Meanwhile, the activities of nitrate reductase (NR), glutamine synthetase (GS), and glutamate synthetase (GOGAT) increased, plant nitrogen concentration increased, and the accumulation of protein increased relatively, which were not conducive to the formation of yield and good quality. After the application of nitrogen fertilizer at the middle and late growth stages, the activities of key enzyme in carbon and nitrogen metabolism in leaves were significantly increased, the aging of leaves was slowed down, and the grain-filling period of rice was prolonged, which were conducive to the increase of yield. With the delay of nitrogen fertilizer application period, nitrogen metabolism became more vigorous, and the protein content in grain had a relative significant increase, resulting in the decrease of the ratio of starch to protein and the ratio of amylose to protein, and the decrease of taste value. Under the experimental condition, normal light intensity combined with nitrogen fertilizer treatment (L1–N3) at the top fourth leaf stage synergistically improved the activities of key enzymes of carbon and nitrogen metabolism in leaves, thus the photosynthetic products and nitrogen-containing compounds were transported to grains in the appropriate proportions. Ultimately, the ratio of starch to protein in grain ranged from 11.43 to 12.03, and the ratio of amylose to protein ranged from 1.34 to 1.50, the rice had low hardness, high viscosity, and balance as well as good taste, high yield, and excellent quality could be obtained simultaneously.

rice; light; nitrogen fertilizer; carbon and nitrogen metabolism; yield; rice quality

10.3724/SP.J.1006.2023.22054

本研究由國(guó)家自然科學(xué)基金項(xiàng)目(31971841), 財(cái)政部和農(nóng)業(yè)農(nóng)村部國(guó)家現(xiàn)代農(nóng)業(yè)產(chǎn)業(yè)技術(shù)體系建設(shè)專(zhuān)項(xiàng)(水稻, CARS-01), 山東省重點(diǎn)研發(fā)計(jì)劃課題項(xiàng)目(2021LZGC020-03), 國(guó)家重點(diǎn)研發(fā)計(jì)劃項(xiàng)目(2022YFD2301401)和江蘇高校優(yōu)勢(shì)學(xué)科建設(shè)工程項(xiàng)目(PAPD)資助。

This study was supported by the National Natural Science Foundation of China (31971841), the China Agriculture Research System of MOF and MARA (Rice, CARS-01), the Key Research Program of Shandong Province, China (2021LZGC020-03), the National Key Research and Development Program of China (2022YFD2301401), and the Priority Subject Program Development of Jiangsu Higher Education Institutions (PAPD).

魏海燕, E-mail: wei_haiyan@163.com, Tel: 0514-87974595

E-mail: 2215502977@qq.com

2022-09-25;

2023-05-24;

2023-05-31.

URL:https://kns.cnki.net/kcms2/detail/11.1809.S.20230530.1505.004.html

This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).