乙矮合剂对不同密度夏玉米花粒期不同部位叶片衰老特性的影响

引用本文

卢霖, 董志强, 董学瑞, 李光彦. . 乙矮合剂对不同密度夏玉米花粒期不同部位叶片衰老特性的影响. 作物学报, 2016, 42(4): 561-573
LU Lin, DONG Zhi-Qiang, DONG Xue-Rui, LI Guang-Yan. . Effects of Ethylene-Chlormequat-Potassium on Characteristics of Leaf Senescence at Different Plant Positions after Anthesis under Different Planting Densities. ACTA AGRONOMICA SINICA, 2016, 42(4): 561-573 复制到剪切板

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乙矮合剂对不同密度夏玉米花粒期不同部位叶片衰老特性的影响

卢霖, 董志强^*, 董学瑞, 李光彦

中国农业科学院作物科学研究所 / 农业部作物生理生态与栽培重点开放实验室, 北京 100081

^* 通讯作者(Corresponding author): 董志强, E-mail: dongzhiqiang@caas.cn, Tel: 010-82106043

第一作者联系方式: E-mail: 932197016@qq.com, Tel: 010-82106043

收稿日期:2015-07-13 接受日期:2016-01-11 网络出版日期:2016-01-26

基金:本研究由国家自然科学基金项目(31470087)和国家粮食丰产科技工程项目(2011BAD16B14, 2012BAD04B01)资助

摘要

为探讨乙矮合剂对密植夏玉米叶片衰老及后期早衰的调控机制, 建立华北夏玉米区密植高产稳产化学调控技术, 以中单909和浚单20为材料, 设置乙矮合剂(ECK)和密度梯度处理, 研究密度梯度对夏玉米花粒期不同部位叶片衰老特性的影响与ECK的调控效应。结果表明, 随密度增加, 两品种花粒期单株叶面积减小且降幅增大; 各叶位叶片的叶绿素相对含量和可溶性蛋白含量呈下降趋势; 超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性呈降低趋势; 丙二醛(MDA)含量则呈增高趋势; 上述指标在叶位和品种间存在差异。ECK处理显著提高各密度不同部位叶片SOD、CAT、POD活性和叶绿素相对含量及可溶性蛋白含量, 显著降低MDA含量; 单株绿叶面积降幅减小, 叶片衰老进程延缓, 衰老程度减轻。ECK处理后, 较高密度群体下(7.5~10.5万株 hm^-2), 中单909和浚单20较各自对照分别增产5.59%~6.63%和6.73%~8.10%。因此, 采用合理的种植密度结合喷施乙矮合剂可作为华北夏玉米区高产栽培的重要技术措施。

关键词: 夏玉米; 乙矮合剂; 种植密度; 叶片衰老; 抗氧化酶

Effects of Ethylene-Chlormequat-Potassium on Characteristics of Leaf Senescence at Different Plant Positions after Anthesis under Different Planting Densities

LU Lin, DONG Zhi-Qiang^*, DONG Xue-Rui, LI Guang-Yan

Institute of Crop Science, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Beijing 100081, China

Fund:This study was supported by the National Natural Science Foundation of China (31470087) and the National Key Technology R&D Program of China (2011BAD16B14, 2012BAD04B01)

Abstract

In order to explore the effects of ethylene-chlormequat-potassium (ECK) on leaf aging and early senescence in summer maize, and provide a theoretical basis for high and stable yields of summer maize under high planting density by chemical regulation technology in North China Plain, a field experiment was conducted using two types of maize hybrids (Zhongdan 909 and Xundan 20) with treatments of ethylene-chlormequat-potassium under different planting densities. The results showed that the increased planting density significantly decreased leaf area (LA) per plant and increased LA reduction rate. With the increase of planting density decreased SPAD value, soluble protein content, and activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) of ear leaf, the third leaf above ear, and the third leaf below ear, while malondialdehyde (MDA) content increased. The above indexes had differences among varieties and leaf positions. ECK treatment significantly increased activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), SPAD value and soluble protein content in leaves at different positions, decreased LA reduction rate, delayed and alleviated leaf senescence. Under the density of ≥7.5×10⁴ plant ha^-1, the yield of Zhongdan 909 and Xundan 20, compared with their own controls, increased by 5.59-6.63% and 6.73-8.10%, respectively. ECK treatment significantly prevented early senescence under higher planting densities, therefore increased yield. Thus, adopting an appropriate planting density combined with ECK application could be an important technique for achieving high grain yield in summer maize production in North China Plain.

Keyword: Summer maize; Ethylene-chlormequat-potassium; Planting density; Leaf senescence; Antioxidant enzyme

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增加种植密度是玉米获得高产的重要途径之一^{[1, 2]}。然而, 增密将导致群体冠层郁闭, 通透性差, 光热资源分布不均, 冠层基部温度低、光照不足; 同时, 增加密度引起耕层根系数量增加, 植株间对有限养分水分资源的激烈竞争使个体生长发育差, 根系活力低, 地上部叶片功能期缩短, 导致花粒期群体早衰^{[3, 4]}。花粒期是玉米产量形成的关键时期, 该时期叶片开始衰老, 叶片功能开始衰退; 已有研究表明, 叶片的衰老伴随着活性氧的积累以及细胞中抗氧化酶活性的降低^[5]。研究发现, 种植密度与叶片衰老密切相关, 王海燕等研究表明, 玉米花粒期不同层位叶片的SPAD值、光合速率、气孔导度、蒸腾速率随密度增加而降低^[6]; 解振兴等^[7]研究表明, 随种植密度增加, 玉米穗位叶保绿度、叶绿素含量下降, 超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性降低, 丙二醛(MDA)含量升高; 乔宏伟等^[8]研究表明, 玉米不同层次叶片的可溶性蛋白含量低密度下均高于高密度下, 而可溶性蛋白含量与植株体内生理代谢的强度密切相关^[9], 并进一步影响着叶片的功能与衰老, 以及光合产物在籽粒中的积累过程和最终的籽粒产量。

玉米籽粒产量形成阶段与叶片衰老过程同步进行, 随灌浆进程发展, 叶片逐渐衰老, 因此, 在此期间延缓叶片衰老有利于增强叶片光合功能, 获得更高产量^[10]。虽然, 将适宜的种植密度和播种方式、行间距配置^[11]相结合, 配合分次施氮肥且适当增加花粒肥比例^[12]等栽培措施相集成^[13], 在一定程度上, 提高了玉米密植群体叶片抗氧化酶活性, 延缓了植株衰老, 在一定密度范围内, 提高了籽粒产量, 但是, 应用化学调控技术可以通过调节作物自身的内源激素平衡, 调控作物的生长发育进程, 调控作物对水分、养分的吸收同化运转, 改善作物自身对环境的适应能力, 最终可以有效改善作物的产量形成, 显著提高产量^{[14, 15, 16]}。研究表明, 外施矮壮素可以提高作物保护酶活性和可溶性蛋白含量, 进而提高作物的抗逆性^{[17, 18]}。适宜浓度的乙烯利可以促进根系生长, 并调控株型结构, 增加玉米产量^{[19, 20]}。

目前, 在华北夏玉米大田生产中, 抗倒伏增产调节剂— — 乙矮合剂(乙烯利∶ 矮壮素=1∶ 3, 含量为28%)应用面积较大, 在密植群体矮化株高、抗倒伏等方面效果显著^{[21, 22]}, 但是, 上述研究均限于夏玉米生育前期, 即六展叶期处理对株型建构、茎秆质量形成和根系建构等方面的影响, 而有关乙矮合剂对生育后期(花粒期— — 即产量形成时期)不同密度群体夏玉米抗早衰效果的研究, 尤其是对不同部位叶片的衰老特性调控效果方面的研究, 尚未见报道。因此, 本试验采用不同基因型品种为试材, 设置乙矮合剂化学调控和密度梯度处理, 研究密度梯度对夏玉米花粒期不同部位叶片抗氧化特性的影响与乙矮合剂的化学调控效应, 探讨乙矮合剂调控玉米叶片抗氧化特性、防止花粒期叶片早衰的生理机制, 为建立华北夏玉米区密植高产稳产化学调控技术提供科学依据。

1 材料与方法

1.1 试验材料与试验设计

以不同基因型品种中单909 (由中国农业科学院作物科学研究所选育, 耐密性较强, 以下简称ZD)和浚单20 (由河南省浚县农业科学研究所选育, 耐密性较差, 以下简称XD)为试材。

试验于2013年和2014年在中国农业科学院新乡试验站进行, 试验地常年平均气温14.3℃, 常年平均降雨量560.6 mm, 年际内降雨分布不均, 大部分集中于6月至9月份, 约占全年降雨量的75%。试验地土壤为黏壤二合土, 土壤含有机质12.55 g kg^-1、全氮1.13 g kg^-1、速效磷16.15 mg kg^-1、速效钾109.95 mg kg^-1, pH 8.1。采用裂区设计, 化学调控处理(TR)为主区, 于六展叶期叶面喷施乙矮合剂0.45 L hm^-2, 每公顷兑水225 L, 对照(CK)喷施等量清水; 密度处理为副区, 设置4.5万株 hm^-2、6.0万株 hm^-2、7.5万株 hm^-2、9.0万株 hm^-2、10.5万株 hm^-2 5个密度水平, 分别用D₁、D₂、D₃、D₄、D₅表示。试验小区为12行区, 60 cm等行距, 小区面积57.6 m², 3次重复。基施复合肥(N∶ P₂O₅∶ K₂O=15∶ 15∶ 15, 总养分≥ 45%) 375 kg hm^-2, 追施尿素600 kg hm^-2, 60%拔节期追施, 40%大口期追施。其他管理同当地大田生产。2013年6月16日播种, 9月26日收获。2014年6月8日播种, 9月20日收获。

乙矮合剂(ethylene-chlormequat-potassium, 以下简称ECK)由中国农业科学院作物科学研究所栽培生理系研制, 黑龙江禾田丰泽兴农科技开发有限公司生产提供。

1.2 测定项目与方法

开花期选取同天开花且长势长相基本相同的单株挂牌标记, 从开花之日起, 每10 d取样1次, 取穗位叶、穗上第3叶、穗下第3叶(去除叶脉后取叶片中部), 液氮速冻后放入-20℃冰柜储存待测生理指标。

取各叶位叶样品0.5 g, 分别加入5 mL pH 7.8磷酸缓冲液, 冰浴研磨, 10 000× g冷冻离心20 min, 上清液即为酶液。

1.2.1 叶面积和叶片衰老程度

从每个小区选择代表性样株3株, 开花后每10 d 一次, 采用长宽系数法, 测定并计算绿叶面积(LA); 参考Tollenaar等^[23]方法, 用2次测得的绿叶面积相对减少的比例来描述叶片衰老程度, 即LA降幅(%) = (LAt2 - LAt1)/ LAt1 × 100。

1.2.2 叶绿素相对含量

采用日本美能达公司产手持式SPAD-502型叶绿素计测定穗位叶、穗上第3叶、穗下第3叶的叶绿素相对含量(SPAD值)。

1.2.3 可溶性蛋白含量

采用考马斯亮蓝G-250染色法测定。吸取酶液20 μ L, 加入考马斯亮蓝G-250溶液3 mL, 混匀, 在室温下静置2 min, 595 nm处比色^[24]。

1.2.4 SOD、POD、CAT活性

参照王爱国等^[25]的方法测定SOD活性, 吸取20 μ L酶液, 加入3 mL SOD 反应液(0.05 mol L^-1pH 7.8磷酸缓冲液1.5 mL, 130 mmol L^-1 Met 0.3 mL, 750 μ mol L^-1 NBT 0.3 mL, 100 μ mol L^-1 EDTA-Na₂ 0.3 mL, 20 μ mol L^-1 FD 0.3 mL, 蒸馏水0.3 mL), 照光30 min, 对照与酶液置相同条件下光照, 空白置于暗处用于调零, 560 nm处比色。参照李忠光等^[26]的方法测定POD活性, 吸取20 μ L酶液加入3 mL POD反应液(1.4 μ L愈创木酚, 0.85 μ L 30% H₂O₂和0.1 mol L^-1 pH 6.0磷酸缓冲液), 470 nm下比色每隔30 s读吸光度增加值。参照林植芳等^[27]的方法测定CAT活性, 吸取50 μ L酶液加2.5 mL CAT反应液(0.5 mL 0.1 mol L^-1 H₂O₂溶液, 2.5 mL 0.1 mol L^-1 pH 7.0磷酸缓冲液), 240 nm下比色, 每隔30 s读取吸光度的下降值。

1.2.5 MDA含量

参照林植芳^[27]的方法测定。1 mL酶液加2 mL 0.6% TBA, 沸水浴15 min, 迅速冷却后离心, 取上清液, 分别在600、532和450 nm 3个波长下比色。

1.2.6 产量及其构成

在每处理小区中选取10 m²称重计产, 并选取20个平均穗调查穗部性状, 测定出籽率和含水率, 计算产量(按14%含水率计)。

1.3 数据处理及统计分析

采用Microsoft Excel 2007作图, SPSS 17.0统计分析, LSD检验处理平均数间差异显著性(P < 0.05^*; P < 0.01^{* *})。两年的试验结果趋势基本一致, 本文采用2014年的数据。

2 结果与分析

2.1 乙矮合剂对不同密度夏玉米花粒期叶片衰老进程的影响

如图1所示, 吐丝期至成熟期, D₁~D₅各密度处理花后每隔10 d叶面积显著下降, ZD降幅分别为2.98%~14.88%、3.91%~19.12%、3.35%~20.49%、8.35%~23.37%和8.98%~22.98%; XD降幅分别为4.90%~15.23%、4.41%~20.58%、7.12%~26.41%、6.01%~23.41%和5.57%~29.69%。可见, 在灌浆过程中两玉米品种单株叶面积降幅随种植密度增加而增大; 且ZD的D₃、D₄、D₅密度处理花后30~40 d叶面积降幅达20%以上, XD的D₂、D₃、D₄、D₅密度在花后30~40 d叶面积降幅达20%以上。

ECK处理后, 显著减小了两玉米品种叶面积降低幅度(P < 0.05^*), ZD-TR花后每隔10 d叶面积降幅较清水对照分别平均减小了14.44%、26.50%、42.47%、40.25%和25.26%; XD-TR较清水对照分别平均减少了18.19%、12.41%、39.44%、38.12%和20.72%。

2.2 乙矮合剂对不同密度夏玉米花粒期不同叶位叶绿素相对含量(SPAD值)的影响

ZD和XD的叶片SPAD值随密度增加而降低, 尤其在花后40 d高密度下叶片SPAD值下降速率较快(图2)。D₁~D₅各密度, 吐丝期两品种各叶位SPAD值无显著差异; 花后20 d开始, 叶片SPAD值随密度增加而减小且下降较快; 花后40 d, D₃~D₅密度下显著低于D₁、D₂密度。穗位叶和穗上3叶花后30~40 d显著下降, 而穗下第3叶花后20~40 d显著下降。

ECK处理提高了花后20~40 d不同叶位SPAD值, 尤以穗位叶和穗下第3叶增幅显著。D₁~D₅各密度, ZD-TR穗上第3叶、穗位叶和穗下第3叶较各自清水对照平均增幅分别为5.43%~9.19%、3.49%~ 7.84%和3.68%~14.86%; XD-TR平均增幅分别为2.71%~9.77%、3.92%~11.34%和2.13%~17.71%。

2.3 乙矮合剂对不同密度夏玉米花粒期不同叶位可溶性蛋白含量的影响

如图3所示, 穗上第3叶D₁~D₅和穗位叶D₁、D₂, 花后20 d开始下降且随密度增加降幅加大; 穗位叶D₃~D₅和穗下第3叶D₁~D₅花后一直呈下降趋势。D₁~D₅各密度, 两品种穗上第3叶和穗位叶的可溶性蛋白含量显著高于穗下第3叶。

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图1 乙矮合剂(ECK)对不同密度夏玉米单株叶面积(LA)和叶面积降幅的影响
ZD-CK: 中单909对照; ZD-TR: 中单909化学调控处理; XD-CK: 浚单20对照; XD-TR: 浚单20化学调控处理; D₁、D₂、D₃、D₄和D₅分别代表种植密度为4.5、6.0、7.5、9.0和10.5万株 hm^-2。Fig. 1 Effect of Ethylene-Chlormequat-Potassium (ECK) on leaf area (LA) per plant and leaf area reduction per plant of summer maize under different planting densities
ZD-CK: Zhongdan 909 control; ZD-TR: Zhongdan 909 treatment; XD-CK: Xundan 20 control; XD-TR: Xundan 20 treatment; D₁, D₂, D₃, D₄, and D₅ denote the planting density of 4.5, 6.0, 7.5, 9.0, and 10.5 × 10⁴ plant hm^-2, respectively.

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图2 乙矮合剂对不同密度夏玉米不同部位叶片叶绿素相对含量的影响
ZD-CK: 中单909对照; ZD-TR: 中单909化学调控处理; XD-CK: 浚单20对照; XD-TR: 浚单20化学调控处理; S₀: 穗位叶; S₀+3: 穗上第3叶; S₀-3: 穗下第3叶; D₁、D₂、D₃、D₄和D₅分别代表种植密度为4.5、6.0、7.5、9.0和10.5万株 hm^-2。Fig. 2 Effect of Ethylene-Chlormequat-Potassium (ECK) on SPAD value of leaves of summer maize under different planting densities
ZD-CK: Zhongdan 909 control; ZD-TR: Zhongdan 909 treatment; XD-CK: Xundan 20 control; XD-TR: Xundan 20 treatment; S₀:ear leaf; S₀+3: the third leaf above ear; S₀-3: the third leaf below ear ; D₁, D₂, D₃, D₄, and D₅ denote the planting density of 4.5, 6.0, 7.5, 9.0, and 10.5 × 10⁴ plant hm^-2, respectively.

ECK处理提高了两品种D₁~D₅密度不同灌浆阶段不同部位叶片可溶性蛋白的含量, 其中, 穗上第3叶花后30~40 d可溶性蛋白含量, ZD-TR和XD-TR较各自清水对照平均提高5.54%~20.20%和13.00%~ 48.34%; 穗位叶花后20~40 d可溶性蛋白含量, ZD-TR和XD-TR增幅分别为13.42%~19.72%和16.43%~62.90%; 穗下第3叶花后20~40 d可溶性蛋白含量, ZD-TR和XD-TR增幅分别为21.15%~ 44.48%和21.67%~61.80%。增幅表现为穗下第3叶> 穗位叶> 穗上第3叶。

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图3 乙矮合剂对不同密度夏玉米不同部位叶片可溶性蛋白含量的影响
ZD-CK: 中单909对照; ZD-TR: 中单909化学调控处理; XD-CK: 浚单20对照; XD-TR: 浚单20化学调控处理; S₀: 穗位叶; S₀+3: 穗上第3叶; S₀-3: 穗下第3叶; D₁、D₂、D₃、D₄和D₅分别代表种植密度为4.5、6.0、7.5、9.0和10.5万株 hm^-2。Fig. 3 Effect of Ethylene-Chlormequat-Potassium (ECK) on SPAD value of leaves of summer maize under different planting densities
ZD-CK: Zhongdan 909 control; ZD-TR: Zhongdan 909 treatment; XD-CK: Xundan 20 control; XD-TR: Xundan 20 treatment; S₀: ear leaf; S₀+3: the third leaf above ear ; S₀-3: the third leaf below ear; D₁, D₂, D₃, D₄, and D₅ denote the planting density of 4.5, 6.0, 7.5, 9.0, and 10.5 × 10⁴ plant hm^-2, respectively.

2.4 乙矮合剂对不同密度夏玉米花粒期不同叶位抗氧化酶(SOD、POD、CAT)活性的影响

2.4.1 对SOD活性的影响

两品种各密度各叶位SOD活性呈单峰曲线变化(图4), 且峰值出现时间不同, 穗上第3叶D₁~D₄出现在花后10 d, D₅出现在花后0 d; 穗位叶D₁~D₂出现在花后0 d, D₃~D₅出现在花后20 d; 穗下第3叶D₁~D₃出现在花后20 d, D₄~D₅出现在花后10 d。D₁~D₅的SOD活性, 随密度增加而降低; 且穗下第3叶> 穗位叶> 穗上第3叶; 品种间以ZD高于XD。

ECK处理提高了两品种各密度各叶位SOD活性。ZD-TR和XD-TR穗上第3叶SOD活性较各自清水对照分别增加6.68%~19.84%和33.54%~46.94%; 穗位叶SOD活性, 分别增加16.49%~32.23%和3.57%~36.72%; 穗下第3叶SOD活性分别增加9.95%~38.27%和16.02%~32.15%。

2.4.2 对POD活性的影响

两品种各密度各叶位POD活性呈单峰曲线变化(图5), 除穗下第3叶外, 峰值均出现在花后20 d。D₁~D₅处理的各叶位POD活性随密度增加而降低; 且ZD表现为穗下第3叶> 穗上第3叶> 穗位叶; XD表现为穗下第3叶> 穗位叶> 穗上第3叶。品种间以ZD高于XD。

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图4 乙矮合剂对不同密度夏玉米不同部位叶片SOD活性的影响
ZD-CK: 中单909对照; ZD-TR: 中单909化学调控处理; XD-CK: 浚单20对照; XD-TR: 浚单20化学调控处理; S₀: 穗位叶; S₀+3: 穗上第3叶; S₀-3: 穗下第3叶; D₁、D₂、D₃、D₄和D₅分别代表种植密度为4.5、6.0、7.5、9.0和10.5万株 hm^-2。Fig. 4 Effect of Ethylene-Chlormequat-Potassium (ECK) on SOD activity of leaves of summer maize under different planting densities
ZD-CK: Zhongdan 909 control; ZD-TR: Zhongdan 909 treatment; XD-CK: Xundan 20 control; XD-TR: Xundan 20 treatment; S₀: ear leaf; S₀+3: the third leaf above ear; S₀-3: the third leaf below ear; D₁, D₂, D₃, D₄, and D₅ denote the planting density of 4.5, 6.0, 7.5, 9.0, and 10.5 × 10⁴ plant hm^-2, respectively.

ECK处理提高了两品种各叶位POD活性, 其中, ZD-TR和XD-TR穗位叶D₁和D₂低密度下差异不显著, D₃~D₅高密度下花后20~40 d差异达显著水平, 平均增幅分别为19.12%~36.39%和34.25%~41.21%; 而穗下第3叶D₁~D₅增幅分别为7.29%~21.75%和18.46%~32.70%。

2.4.3 对CAT活性的影响

D₁~D₅密度下CAT活性的变化在穗上第3叶呈单峰曲线, 峰值为花后20 d, 且随密度增加差异不显著; 在穗位叶和穗下第3叶则呈下降趋势; 品种间以ZD高于XD (图6)。

ECK处理提高了两品种各叶位CAT活性。其中, 穗上第3叶CAT活性在D₄~D₅高密度下增幅达显著水平, ZD-TR和XD-TR平均增幅分别为22.13%~ 24.90%和57.62%~68.16%。D₁~D₅密度下穗位叶在花后20~40 d增幅达显著水平, ZD-TR和XD-TR平均增幅分别为6.56%~59.56%和36.77%~123.43%; 穗下第3叶(除了D₁、D₂、D₃密度下花后0 d)差异均达显著水平, 平均增幅分别为22.47%~77.79%和63.28%~156.28%。

2.5 乙矮合剂对不同密度夏玉米花粒期不同叶位丙二醛(MDA)含量的影响

由图7可知, 同一密度处理下, ZD和XD不同叶位叶片膜质过氧化产物MDA 含量在花粒期总体表现为上升的趋势且XD高于ZD。随密度增加, MDA含量升高, 且穗位叶和穗下第3叶升高的趋势更为显著。

ECK处理降低了两品种玉米各叶位叶片MDA含量。D₁~D₅密度下ZD-TR和XD-TR穗上第3叶MDA含量比清水对照平均下降7.09%~15.45%和14.89%~28.44%; 穗位叶平均下降16.45%~19.74%和17.72%~25.68%; 穗下第3叶平均下降8.43%~ 17.03%和11.44%~24.32%。

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图5 乙矮合剂对不同密度夏玉米不同部位叶片POD活性的影响
ZD-CK: 中单909对照; ZD-TR: 中单909化学调控处理; XD-CK: 浚单20对照; XD-TR: 浚单20化学调控处理; S₀: 穗位叶; S₀+3: 穗上第3叶; S₀-3: 穗下第3叶; D₁、D₂、D₃、D₄和D₅分别代表种植密度为4.5、6.0、7.5、9.0和10.5万株 hm^-2。Fig. 5 Effect of Ethylene-Chlormequat-Potassium (ECK) on POD activity of leaves of summer maize under different planting densities
ZD-CK: Zhongdan 909 control; ZD-TR: Zhongdan 909 treatment; XD-CK: Xundan 20 control; XD-TR: Xundan 20 treatment; S₀: ear leaf; S₀+3: the third leaf above ear; S₀-3: the third leaf below ear; D₁, D₂, D₃, D₄, and D₅ denote the planting density of 4.5, 6.0, 7.5, 9.0, and 10.5 × 10⁴ plant hm^-2 , respectively.

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图6 乙矮合剂对不同密度夏玉米不同部位叶片CAT活性的影响
ZD-CK: 中单909对照; ZD-TR: 中单909化学调控处理; XD-CK: 浚单20对照; XD-TR: 浚单20化学调控处理; S₀: 穗位叶; S₀+3: 穗上第3叶; S₀-3: 穗下第3叶; D₁、D₂、D₃、D₄和D₅分别代表种植密度为4.5、6.0、7.5、9.0和10.5万株 hm^-2。Fig. 6 Effect of Ethylene-Chlormequat-Potassium (ECK) on CAT activity of leaves of summer maize under different planting densities
ZD-CK: Zhongdan 909 control; ZD-TR: Zhongdan 909 treatment; XD-CK: Xundan 20 control; XD-TR: Xundan 20 treatment; S₀: ear leaf; S₀+3: the third leaf above ear leaf ; S₀-3: the third leaf below ear leaf; D₁, D₂, D₃, D₄, and D₅ denote the planting density of 4.5, 6.0, 7.5, 9.0, and 10.5 × 10⁴ plant hm^-2, respectively.

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图7 乙矮合剂对不同密度夏玉米不同部位叶片MDA含量的影响
ZD-CK: 中单909对照; ZD-TR: 中单909化学调控处理; XD-CK: 浚单20对照; XD-TR: 浚单20化学调控处理; S₀: 穗位叶; S₀+3: 穗上第3叶; S₀-3: 穗下第3叶; D₁、D₂、D₃、D₄和D₅分别代表种植密度为4.5、6.0、7.5、9.0和10.5万株 hm^-2。Fig. 7 Effect of Ethylene-Chlormequat-Potassium (ECK) on MDA content of leaves of summer maize under different planting densities
ZD-CK: Zhongdan 909 control; ZD-TR: Zhongdan 909 treatment; XD-CK: Xundan 20 control; XD-TR: Xundan 20 treatment; S₀: ear leaf; S₀+3: the third leaf above ear; S₀-3: the third leaf below ear; D₁, D₂, D₃, D₄, and D₅ denote the planting density of 4.5, 6.0, 7.5, 9.0, and 10.5 × 10⁴ plant hm^-2, respectively.

2.6 不同密度夏玉米花后叶片衰老与抗氧化指标的相关性分析

绿叶面积及其降低幅度(失绿)可作为评价叶片衰老程度的指标。将各密度两品种各叶位叶片衰老指标与抗氧化酶系活性、MDA含量、SPAD值及可溶性蛋白含量之间进行相关分析, 结果如表1所示。ZD-CK叶片衰老与SOD、POD、CAT活性呈极显著负相关, 与SPAD值和可溶性蛋白含量呈极显著负相关; 其叶片MDA含量与SOD、POD和CAT活性呈极显著负相关, 与SPAD值和可溶性蛋白含量呈极显著负相关。而ZD-TR叶片衰老与POD活性相关性不显著, 叶片MDA含量与POD活性相关性不显著, 其他指标与ZD-CK一致。XD-CK和XD-TR的相关分析结果一致, 叶片衰老与SOD、CAT活性呈极显著负相关, 与SPAD值和可溶性蛋白含量呈极显著负相关; 其叶片MDA含量与SOD、CAT活性呈极显著负相关, 与SPAD值和可溶性蛋白含量呈极显著负相关。

2.7 乙矮合剂对不同密度夏玉米产量及产量构成的影响

2.7.1 对产量的影响由图8可知, 两玉米品种产量随密度增加呈先增加后降低趋势, D₃密度达最大值, 且ZD的产量高于XD。ZD在D₃密度下比D₁和D₂分别高1654.31 kg和646.54 kg, 比D₄和D₅分别高555.10 kg和596.88 kg。XD在D₃密度下比D₁和D₂分别高1256.30 kg和557.66 kg, 比D₄和D₅分别高225.63 kg和396.38 kg。ECK处理后, 高密群体(D₃、D₄、D₅) ZD-TR和XD-TR的产量与各自CK相比, 差异达显著水平(P< 0.05^*), ZD-TR在D₃、D₄、D₅密度下分别增产5.59%、6.11%和6.43%; XD-TR在D₃、D₄、D₅密度的增幅分别为7.51%、8.10%和6.73%。

表1 不同密度夏玉米叶片衰老与抗氧化酶(SOD、POD、CAT)活性、MDA、可溶性蛋白含量及SPAD值的相关性 Table 1 Correlation coefficients of leaves senescence with antioxidant enzyme (SOD, POD, CAT) activities, MDA, soluble protein contents, and SPAD value in summer maize under different planting densities

2.7.2 对产量构成因素的影响

如表2所示, D₁~D₅密度下两品种有效穗数随密度增加而增加; ECK处理后, D₃、D₄、D₅密度下增加显著, ZD-TR的增幅分别为2.04%、4.58%、2.42%, XD-TR的增幅分别为5.91%、4.24%、4.31%。在D₁~D₅密度下, 两品种穗行数随密度增加有所降低但差异不显著; 行粒数随密度增加而显著减少。ECK处理后, ZD和XD的行粒数较各自清水对照均增加。两品种的穗行数略有增加, 但差异不显著。在D₁~D₅密度下, ZD-TR的行粒数增幅分别为3.30%、0.68%、2.89%、7.05%、2.13%; XD-TR的增幅分别为2.08%、2.08%、6.81%、9.66%、4.60%。两玉米品种千粒重随密度的增加而降低, 品种间表现为ZD大于XD。ECK处理后, 不同密度处理下两品种千粒重均高于各自清水对照, 在D₃、D₄、D₅密度下达显著水平; 在D₃、D₄、D₅密度下, ZD-TR的增幅分别为4.46%、6.99%、4.31%; XD-TR的增幅分别为5.96%、4.69%、5.90%。

表2 乙矮合剂对不同密度夏玉米产量及产量构成的影响 Table 2 Effect of Ethylene-Chlormequat-Potassium (ECK) on yield components of summer maize under different planting densities

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图8 乙矮合剂对不同密度夏玉米产量的影响
ZD-CK: 中单909对照; ZD-TR: 中单909化学调控处理; XD-CK: 浚单20对照; XD-TR: 浚单20化学调控处理; 图柱上小写字母不同表示在0.05水平上差异显著。Fig. 8 Effect of Ethylene-Chlormequat-Potassium (ECK) on yield of two maize lines under different plant densities
ZD-CK: Zhongdan 909 control; ZD-TR: Zhongdan 909 treatment; XD-CK: Xundan 20 control; XD-TR: Xundan 20 treatment. Bars superscripted by different lowercase letters are significantly different at P< 0.05.

3 讨论

花粒期是玉米产量形成的关键时期, 随着籽粒灌浆的进程, 叶片的功能逐渐衰退, 叶片失绿, 衰老脱落, 有效光合叶面积减小, 因此, 在此期间保持较高的光合面积, 有利于增加后期干物质生产和积累, 有利于提高产量。叶片失绿速率、持绿时间和绿叶面积等可作为评价衰老进程和程度的指标^{[7, 28, 29]}。增加种植密度导致作物冠层郁闭, 光、温和CO₂分布不均, 直接影响叶片的光合效率和干物质积累, 导致有效光合面积减少, 叶片早衰。本研究结果, 不同种植密度处理下夏玉米单株叶面积从灌浆中后期开始下降, 特别是进入乳熟期后迅速下降, 并随种植密度的增加降幅加大, ZD和XD在D₃、D₄、D₅密度处理下花后30~40 d叶面积降幅达20%以上, 与前人研究结果一致^[3]; 而ECK处理, 减小了两玉米品种叶面积降低幅度, 延缓叶片衰老, 其中, XD-TR在D₅密度处理下花后30~40 d叶面积比对照增加达20%以上。

增加种植密度导致玉米穗位叶保绿度、叶绿素含量下降^[7], 花粒期不同层位叶片的SPAD值和可溶性蛋白含量降低^{[6, 8]}; 本研究发现, 花后20 d (灌浆中期)是叶片叶绿素含量变化的转折点, 该时期随密度增加叶片SPAD值开始快速下降, 且D₃~D₅密度处理下显著低于D₁、D₂密度; 至成熟期这种趋势最为显著且穗下第3叶对密度的反应也最为敏感。ECK处理提高了叶片SPAD值, 而且, ECK处理小区和清水对照小区玉米叶片衰老进程出现差异的临界点正是开花后20 d。因此, 喷施乙矮合剂有利于延缓中下部叶片的衰老, 有利于灌浆中后期叶片维持较高的有效光合面积。

叶片衰老过程是活性氧代谢失调的过程, 而SOD、POD和CAT是植物体内最重要的活性氧清除酶类^[5]。水分、温度和养分亏缺等逆境胁迫条件以及增加种植密度, 均导致玉米叶片的保护酶活性提高, 从而有效减轻膜脂过氧化程度^{[12, 14, 30]}。本研究发现, 随密度增加, SOD、POD、CAT活性降低, 且对密度的响应存在叶位和品种的差异。ECK处理显著提高了两品种各密度各叶位SOD活性; 显著提高两品种穗位叶D₃~D₅密度下花后20~40 d和穗下第3叶各密度处理下的POD活性; 显著提高两品种穗上第3叶在D₄~D₅高密度下CAT活性、穗位叶各密度在花后20~40 d的CAT活性、穗下第3叶(除了D₁、D₂、D₃密度下花后0 d)的CAT活性。相关分析表明, ZD叶片衰老进程与SOD、POD、CAT活性极显著负相关, XD与SOD、CAT活性显著负相关, 且MDA含量与SOD、CAT活性极显著负相关。ECK处理显著提高了不同叶位叶片SOD、POD、CAT活性, 显著降低了膜脂过氧化产物含量, 尤其对下部叶片更为显著, 使叶片衰老进程延缓, 衰老程度减轻。王永军等^[10]研究发现, 不同产量群体的不同叶位保护酶活性也存在差异, 即超高产群体叶片衰老过程中, 上部和中部叶片SOD活性较高, 下部叶片则以SOD、POD和CAT三者活性较高; 普通产量群体仅中部叶片POD和CAT活性较高。可见, 下部叶片SOD、POD、CAT活性高是保障群体高产的有利条件。

进一步分析, 我们得到如下乙矮合剂处理提高密植玉米的抗逆性、延缓衰老的原因。第一, ECK主成分之一矮壮素能够提高作物抗氧化系统酶活性和可溶性蛋白含量, 降低活性氧产生速率, 保持膜完整性, 提高抗逆性^{[17, 18]}, 主成分之二乙烯利可以促进根系生长, 并调控株型结构, 增加玉米产量^{[19, 20]}。第二, ECK处理能够改善玉米密植群体的株型结构, 提高茎秆抗倒伏能力, 提高耐密性, 使其更适于密植^{[21, 22]}。第三, ECK处理能够提高NR活性和GS活性, 促进氮素同化作用, 进而提高叶片中叶绿素、可溶性蛋白和游离氨基酸含量, 维持玉米体内基本代谢正常进行(另文发表)。

产量与种植密度呈二次曲线关系^[31], 当密度超过适宜密度时, 对光温水肥的竞争导致群体恶化, 叶片早衰直接影响着籽粒灌浆的进程, 最终影响产量和品质^[32]。本研究发现, 增加种植密度导致叶片SOD、POD和CAT活性降低, MDA含量升高; 叶片叶绿素和可溶性蛋白含量降低, 叶片早衰, 以及最终产量的下降。前人研究表明, 玉米中下部叶片保护酶活性高和膜脂过氧化程度低是近代玉米品种高产抗逆的内在因素^[33], 而ECK处理提高了穗位叶和基部叶片SOD、POD和CAT活性, 提高了可溶性蛋白含量和叶绿素含量, 降低了膜脂过氧化程度, 提高了作物的抗逆性, 延缓了叶片的衰老进程, 最终提高了产量。

4 结论

中单909和浚单20不同密度群体花粒期单株叶面积随密度增加呈降低趋势且降幅增大, 花后30~40 d的降幅高达20%以上。灌浆中后期(开花后20~40 d), 不同叶位叶片的叶绿素和可溶性蛋白含量显著下降, SOD、CAT、POD活性呈降低趋势, MDA含量则呈增高趋势, 叶片呈现早衰趋势; 上述指标均存在叶位和品种间差异。ECK处理能显著提高各密度不同部位叶片SOD、CAT、POD活性和叶绿素相对含量及可溶性蛋白含量, 降低MDA含量; 增加单株叶面积, 叶面积降幅减小, 绿叶面积增加。因此, ECK处理有助于延缓叶片衰老进程, 减轻衰老程度, 保证植物体内正常的代谢, 改善产量构成因素, 最终提高产量。

The authors have declared that no competing interests exist.

作者已声明无竞争性利益关系。

参考文献

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[1]	Duvick D N. The contribution of breeding to yield advances in maize (Zea mays L. ). Adv Agron, 2005, 86: 83-145 [本文引用:1]
[2]	钱春荣, 于洋, 宫秀杰, 姜宇博, 赵杨, 王俊河, 杨忠良, 张卫建. 黑龙江省不同年代玉米杂交种产量对种植密度和施氮水平的响应. 作物学报, 2012, 38: 1864-1874 Qian C R, Yu Y, Gong X J, Jiang Y B, Zhao Y, Wang J H, Yang Z L, Zhang W J. Response of grain yield to plant density and nitrogen application rate for maize hybrids released from different eras in Heilongjiang Province. Acta Agron Sin, 2012, 38: 1864-1874 (in Chinese with English abstract) [本文引用:1]
[3]	吕丽华, 陶洪斌, 夏来坤, 张雅杰, 赵明, 赵久然, 王璞. 不同种植密度下的夏玉米冠层结构及光合特性. 作物学报, 2008, 34: 447-455 Lü L H, Tao H B, Xia L K, Zhang Y J, Zhao M, Zhao J R, Wang P. Canopy structure and photosynthesis traits of summer maize under different planting densities. Acta Agron Sin, 2008, 34: 447-455 (in Chinese with English abstract) [本文引用:2]
[4]	李宗新, 陈源泉, 王庆成, 刘开昌, 高旺盛, 隋鹏. 高产栽培条件下种植密度对不同类型玉米品种根系时空分布动态的影响. 作物学报, 2012, 38: 1286-1294 Li Z X, Chen Y Q, Wang Q C, Liu K C, Gao W S, Sui P. Influence of planting density on root spatio-temporal distribution of different types of maize under high-yielding cultivation conditions. Acta Agron Sin, 2012, 38: 1286-1294 (in Chinese with English abstract) [本文引用:1]
[5]	Prochazkova D, Saiaram R K, Srovatava G C, Singh D V. Oxidative stress and antioxidant activity as the basis of senescence in maize leaves. Plant Sci, 2001, 161: 765-771 [本文引用:2]
[6]	王海燕, 高聚林, 王志刚, 孙继颖, 于晓芳, 高英波, 贾宁, 叶君, 吕佳雯. 高密度对超高产春玉米花粒期叶片衰老与根系活力的影响. 玉米科学, 2012, 20: 75-81 Wang H Y, Gao J L, Wang Z G, Sun J Y, Yu X F, Gao Y B, Jia N, Ye J, Lü J W. Effects of high planting density on super high-yielding spring maize leaf senescence and root activity at anthesis and kernel stage. Maize Sci, 2012, 20: 75-81 [本文引用:2]
[7]	解振兴, 董志强, 兰宏亮, 高娇, 朱平, 彭畅. 磷酸胆碱合剂对不同种植密度玉米叶片衰老生理的影响. 核农学报, 2012, 26: 157-163 Xie Z X, Dong Z Q, Lan H L, Gao J, Zhu P, Peng C. Effect of ECK mixture treatment on maize leaf senescence under different planting densities. J Nucl Agric Sci, 2012, 26: 157-163 (in Chinese with English abstract) [本文引用:3]
[8]	乔宏伟, 武月莲, 王志红, 侯辉. 不同玉米群体灌浆期叶片生理特性的研究. 内蒙古民族大学学报(自然科学版), 2008, (6): 637-639 Qiao H W, Wu Y L, Wang Z H, Hou H. Study on leaves physiological characteristic of different maize population at filling stage. J Inner Mongolia Univ Nationalities (Nat Sci Edn), 2008, (6): 637-639 [本文引用:2]
[9]	印莉萍, 柴小清, 李丹, 张承谦, 洪剑明, 刘祥林, 赵微平. 不同小麦品种叶片衰老过程中谷氨酰胺合成酶和蛋白水解酶的活性变化. 山西师大学报, 1997, (11): 46-49 Yin L P, Chai X Q, Li D, Zhang C Q, Hong J M, Liu X L, Zhao W P. Changes of glutamine synthesis and proteolyase in different wheat speicies during the leaves nature senescence. J Shanxi Norm Univ, 1997, (11): 46-49 (in Chinese with English abstract) [本文引用:1]
[10]	王永军, 杨今胜, 袁翠平, 柳京国, 李登海, 董树亭. 超高产夏玉米花粒期不同部位叶片衰老与抗氧化酶特性. 作物学报, 2013, 39: 2183-2191 Wang Y J, Yang J S, Yuan C P, Liu J G, Li D H, Dong S T. Characteristics of senescence and antioxidant enzyme activities in leaves at different plant parts of summer maize with the super-high yielding potential after anthesis. Acta Agron Sin, 2013, 39: 2183-2191 (in Chinese with English abstract) [本文引用:2]
[11]	李洪岐, 蔺海明, 梁书荣, 赵会杰, 王俊忠. 密度和种植方式对夏玉米酶活性和产量的影响. 生态学报, 2012, 32: 6584-6590 Li H Q, Lin H M, Liang S R, Zhao H J, Wang J Z. Effects of planting densities and modes on activities of some enzymes and yield in summer maize. Acta Ecol Sin, 2012, 32: 6584-6590 (in Chinese with English abstract) [本文引用:1]
[12]	吕鹏, 张吉旺, 刘伟, 杨今胜, 董树亭, 刘鹏, 李登海. 施氮时期对高产夏玉米氮代谢关键酶活性及抗氧化特性的影响. 应用生态学报, 2012, 23: 1591-1598 Lü P, Zhang J W, Liu W, Yang J S, Dong S T, Liu P, Li D H. Effects of nitrogen application period on the nitrogen metabolism key enzymes activities and antioxidant characteristics of high-yielding summer maize. Chin J Appl Ecol, 2012, 23: 1591-1598 (in Chinese with English abstract) [本文引用:2]
[13]	朱昆仑, 靳立斌, 董树亭, 赵斌, 刘鹏, 张吉旺. 综合农艺管理对夏玉米叶片衰老特性的影响. 中国农业科学, 2014, 47: 2949-2959 Zhu K L, Jin L B, Dong S T, Zhao B, Liu P, Zhang J W. Effects of integrated agronomic practices on leaf senescence physiological characteristics of summer maize. Sci Agric Sin, 2014, 47: 2949-2959 [本文引用:1]
[14]	徐田军, 董志强, 高娇, 陈传晓, 焦浏, 解振兴. 聚糠萘水剂对不同积温带玉米叶片衰老和籽粒灌浆速率的影响. 作物学报, 2012, 38: 1698-1709 Xu T J, Dong Z Q, Gao J, Chen C X, Jiao L, Xie Z X. Effect of PASP-KT-NAA on leaf senescence and grain filling rate during the grain-filling period in different temperature zones. Acta Agron Sin, 2012, 38: 1698-1709 (in Chinese with English abstract) [本文引用:2]
[15]	高娇, 董志强, 徐田军, 陈传晓, 焦浏, 卢霖, 董学瑞. 聚糠萘水剂对不同积温带玉米花后叶片氮同化的影响. 生态学报, 2014, 34: 2938-2947 Gao J, Dong Z Q, Xu T J, Chen C X, Jiao L, Lu L, Dong X R. Effects of PASP-KT-NAA on maize leaf nitrogen assimilation after florescence over different temperature gradients. Acta Ecol Sin, 2014, 34: 2938-2947 (in Chinese with English abstract) [本文引用:1]
[16]	杨东清, 李玉玲, 倪英丽, 尹燕枰, 崔正勇, 张永太, 马仁元, 王振林. 外源ABA和6-BA对不同持绿型小麦籽粒灌浆进程及蛋白质含量影响. 作物学报, 2014, 40: 301-312 Yang D Q, Li Y L, Ni Y L, Yin Y P, Cui Z Y, Zhang Y T, Ma R Y, Wang Z L. Effects of exogenous ABA and 6-BA on protein content and grain filling process in different types of stay green wheat. Acta Agron Sin, 2014, 40: 301-312 (in Chinese with English abstract) [本文引用:1]
[17]	Wang H Q, Xiao L G, Tong J H. Foliar application of chlorocholine chloride improves leaf mineral nutrition, antioxidant enzyme activity, and tuber yield of potato (Solanum tuberosum L. ). Sci Hortic, 2010, 125: 521-523 [本文引用:2]
[18]	冯斗, 张涛, 禤维言, 胡蔚东. 3种生长延缓剂对甜高粱幼苗生长和生理特性的影响. 热带作物学报, 2009, 30: 1468-1472 Feng D, Zhang T, Xuan W Y, Hu W D. Effects of three retardants on growth and physiological properties of sweet sorghum seedlings. Chin J Trop Crops, 2009, 30: 1468-1472 (in Chinese with English abstract) [本文引用:2]
[19]	葛建军, 朱林, 张国良, 韩文节, 殷玉宏, 李勇. 乙烯利对花生氮代谢和光合特性的影响. 花生学报, 2008, 37: 22-27 Ge J J, Zhu L, Zhang G L, Han W J, Yin Y H, Li Y. Effects of ethephon on nitrogen metabolism and photosynthesis characters of peanut. J Peanut Sci, 2008, 37: 22-27 (in Chinese with English abstract) [本文引用:2]
[20]	卫晓轶, 张明才, 李召虎, 段留生. 不同基因型玉米对乙烯利调控反应敏感性的差异. 作物学报, 2011, 37: 1819-1827 Wei X T, Zhang M C, Li Z H, Duan L S. Differences in responding sensitivity to ethephon among different maize genotypes. Acta Agron Sin, 2011, 37: 1819-1827 (in Chinese with English abstract) [本文引用:2]
[21]	薛金涛, 张保明, 董志强, 赵明, 黄长玲. 化学调控对玉米抗倒性及产量的影响. 玉米科学, 2009, 17: 91-98 Xue J T, Zhang B M, Dong Z Q, Zhao M, Huang C L. Effects of chemical regulation on lodging and yield of maize. J Maize Sci, 2009, 17: 91-98 (in Chinese with English abstract) [本文引用:2]
[22]	卢霖, 董志强, 董雪瑞, 焦浏, 李光彦, 高娇. 乙矮合剂对不同密度夏玉米茎秆抗倒伏能力及产量的影响. 作物杂志, 2015, (2): 70-77 Lu L, Dong Z Q, Dong X R, Jiao L, Li G Y, Gao J. Effects of Ethylene-Chlormequat-Potassiumon stem lodging-resistance and yield of summer maize under different sowing densities. Crops, 2015, (2): 70-77 (in Chinese with English abstract) [本文引用:2]
[23]	Tollenaar M, Daynard T B. Leaf senescence in short season maize hybrids. Can J Plant Sci, 1978, 58: 869-874 [本文引用:1]
[24]	陈建勋, 王晓峰. 植物生理学实验指导. 广州: 华南理工大学出版社, 2002. pp 35-128 Chen J X, Wang X F. Experiments Instructions of Plant Physiology. Guangzhou: Huanan Technology University Publishers, 2002. pp 35-128(in Chinese) [本文引用:1]
[25]	王爱国, 罗广华. 植物的超氧物自由基与羟胺反应的定量关系. 植物生理学通讯, 1990, (6): 55-57 Wang A G, Luo G H. Quantitative relation between the reaction of hydroxylamine and superoxide anion radicals in plants. Plant Physiol Commun, 1990, (6): 55-57 (in Chinese) [本文引用:1]
[26]	李忠光, 李江鸿, 杜朝昆, 黄号栋, 龚明. 在单一提取系统中同时测定五种植物抗氧化酶. 云南师范大学学报(自然科学版), 2002, 22(6): 44-48 Li Z G, Li J H, Du C K, Huang H D, Gong M. Simultaneous measurement of five antioxidant enzyme activities using a single extraction system. J Yunnan Norm Univ (Nat Sci Edn), 2002, 22(6): 44-48 (in Chinese with English abstract) [本文引用:1]
[27]	林植芳, 李双顺, 林桂珠, 孙谷畴, 郭俊彦. 水稻叶片的衰老与超氧物歧化酶活性及脂质过氧化作用的关系. 植物学报, 1984, 26: 605-615 Lin Z F, Li S S, Lin G Z, Sun G C, Guo J Y. Superoxide dismutase activity and lipidperoxidation in relation to senescence of rice leaves. Acta Bot Sin, 1984, 26: 605-615 (in Chinese) [本文引用:2]
[28]	Colomb B, Kiniry J R, Debaeke P. Effect of soil phosphorus on leaf development and senescence dynamics of field-grown maize. Agron J, 2000, 92: 428-435 [本文引用:1]
[29]	Erley G S, Begum N, Worku M, Bänziger M, Horst W J. Leaf senescence induced by nitrogen deficiency as indicator of genotypic differences in nitrogen efficiency in tropical maize. J Plant Nutr Soil Sci, 2007, 170: 106-114 [本文引用:1]
[30]	胡秀丽, 李艳辉, 杨海荣, 刘全军, 李潮海. HSP70可提高干旱高温复合胁迫诱导的玉米叶片抗氧化防护能力. 作物学报, 2010, 36: 636-644 Hu X L, Li Y H, Yang H R, Liu Q J, Li C H. Heat shock protein 70 may improve the ability of antioxidant defense induced by the combination of drought and heat in maize leaves. Acta Agron Sin, 2010, 36: 636-644 (in Chinese with English abstract) [本文引用:1]
[31]	宋振伟, 齐华, 张振平, 钱春荣, 郭金瑞, 邓艾兴, 张卫建. 春玉米中单909农艺性状和产量对密植的响应及其在东北不同区域的差异. 作物学报, 2012, 38: 2267-2277 Song Z W, Qi H, Zhang Z P, Qian C R, Guo J R, Deng A X, Zhang W J. Effects of plant density on agronomic traits and yield in spring maize Zhongdan 909 and their regional differences in northeast China. Acta Agron Sin, 2012, 38: 2267-2277 (in Chinese with English abstract) [本文引用:1]
[32]	丰明乾, 孙俊荣, 郭蔼光. 小麦灌浆期旗叶蛋白质运转与籽粒蛋白质积累的关系. 陕西农业科学, 1999, (2): 1-3 Feng M Q, Sun J R, Guo A G. The relation of wheat flag leaf protein operation and grain protein accumulation during the grain-filling period. Shaanxi J Agric Sci, 1999, (2): 1-3 (in Chinese with English abstract) [本文引用:1]
[33]	王空军, 胡昌浩, 董树亭, 刘开昌, 孙庆泉. 我国不同年代玉米品种开花后叶片保护酶活性及膜脂过氧化作用的演进. 作物学报, 1999, 25: 700-706 Wang K J, Hu C H, Dong S T, Liu K C, Sun Q Q. Changes of the protective enzyme activities and lipid peroxidation after anthesis among maize varieties planted in different years. Acta Agron Sin, 1999, 25: 700-706 [本文引用:1]

2005

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... 增加种植密度是玉米获得高产的重要途径之一^[1,2] ...

2012

0.0

钱春荣, 于洋, 宫秀杰, 姜宇博, 赵杨, 王俊河, 杨忠良, 张卫建. 黑龙江省不同年代玉米杂交种产量对种植密度和施氮水平的响应. 作物学报, 2012, 38: 1864-1874

Qian C

, Yu

, Gong X

, Jiang Y

, Zhao

, Wang J

, Yang Z

, Zhang W

Response of grain yield to plant density and nitrogen application rate for maize hybrids released from different eras in Heilongjiang Province.

Acta Agron Sin, 2012, 38: 1864-1874 (in Chinese with English abstract)

Eight typical maize hybrids released over 1970s to 2000s in Heilongjiang province were selected to investigate the productivity response to nitrogen fertilizer and plant density in 2009 and 2010. During the variety improvement period from 1970s to 2000s, the yield gains per plant and per unit area were 19.96 g 10 a -1 and 790 kg ha -1 10 a -1 , respectively, while the rates of lodging and barren plant decreased significantly. The plant height, ear height, leaf area per plant, kernel number per ear and 1000-kernel weight of newer hybrids were higher than those of older varieties. For all hybrids released in each era, grain yield per plant decreased with increasing plant density, while grain yield per unit area showed a parabolic shape response. The theoretical optimal density for the highest yield rose by 3 507 plants ha -1 10 yr -1 . The barren plant rates of all hybrids increased with the density increasing, and the lodging rates rose only for the older hybrids released in 1970s and 1980s. Higher plant population led to decreases in the agronomic indicators of plant height , leaf area per plant, kernel number per ear and 1000 kernel weight and the increase in the ear height. Higher nitrogen application rate tended to promote the agronomic indicators of plant height, ear height, leaf area and 1000-kernel weight. However, at the nitrogen application rate ranging from 150 kg ha -1 to 450 kg ha -1 , no significant increase was found in the yields for all hybrids released in the same era. There were significant interactions among density, nitrogen and era on the yield and agronomic traits. Compared with the present situations of maize variety and cropping technique, the above results indicated that there are great potentials in yield gains from new variety breeding and cultivation technique innovation for higher-yield with higher-efficiency through increasing plant density with unchanged nitrogen application rate in Northeast China.

明确不同年代春玉米生产力对种植密度和氮肥水平的响应特征及其趋势，对高产高效的耐密品种选育和密植抗倒栽培具有重要的理论参考和技术指导意义。本文以黑龙江近50年来第一积温带大面积种植的8个典型春玉米品种为材料，于2009和2010年进行密度和施肥的田间试验，比较不同年代主栽品种生产力演变特征。结果显示，黑龙江省1970s—2000s玉米品种更替过程中，单株生产力与群体产量均明显提高，平均增幅分别为16.96 g 10年 -1 和790 kg hm -2 10年 -1 ；植株空秆率和倒伏率显著下降，株高、穗位、单株叶面积、穗粒数、千粒重显著提高。随着密度的提高，各年代玉米的单株产量呈显著下降趋势，群体产量呈抛物线形上升，群体最高产量的理论密度增幅为3 507株 hm -2 10 年 -1 ；空秆率显著提高，但倒伏率仅1970s和1980s的品种呈递增趋势；株高、单株叶面积、棒三叶面积、穗粒数与千粒重均呈现下降趋势，穗位随密度增加呈显著上升趋势。各年代品种株高、穗位、单株叶面积和千粒重随氮肥水平提高呈增加趋势。在150~450 kg hm -2 的施氮水平范围，随着氮肥水平的提高，各年代品种增产效果不明显。各主要指标在年代、密度和氮肥水平之间存在显著的互作效应。对照东北玉米现有的品种特性、种植密度和施肥现状表明，选育耐密品种和实施密植抗倒栽培的增产潜力大，在现在的施肥水平上进一步提高种植密度是东北春玉米高产增效耕作栽培的技术创新方向。

... 增加种植密度是玉米获得高产的重要途径之一^[1,2] ...

2008

0.0

吕丽华, 陶洪斌, 夏来坤, 张雅杰, 赵明, 赵久然, 王璞. 不同种植密度下的夏玉米冠层结构及光合特性. 作物学报, 2008, 34: 447-455

Lü L

, Tao H

, Xia L

, Zhang Y

, Zhao

, Zhao J

, Wang

Canopy structure and photosynthesis traits of summer maize under different planting densities.

Acta Agron Sin, 2008, 34: 447-455 (in Chinese with English abstract)

Canopy structure has strong effects on photosynthesis and grain yield in maize ( Zea mays L.). Planting density is one of the most important factors that can regulate canopy structure. Many researches have shown that leaf area index (LAI) and leaf area duration (LAD) increase accordantly with the proper increase of planting density, but the percent transmission decreases sharply under excessive high density, resulting in uneven light distribution within canopy and photosynthesis reduction. We need to know which proper planting densities for cultivars lead to little influence on photosynthesis and higher grain yield in summer maize. However, so far few reports on this topic have been found and no quantitative criteria can be used in evaluating canopy structure of different maize cultivars. Therefore, we conducted an experiment with three cultivars and three planting densities in the field having medium soil fertility and application of 180 kg N ha -1 in Wuqiao Experimental Station (37°41′02″N，116°37′23″E) of China Agricultural University in 2006 to establish such quantitative criteria for high yielding cultivars in North China Plain. The split plot design was employed with main plot of plant density (low, medium, and high respectively), sub-plot of cultivar (CF008, Zhengdan 958, and Jinhai 5 respectively), and three replicates in each sup-plot. According to plant type, the densities of three cultivars were 9.75×104 (low), 11.25×104 (medium), and 12.45×104 (high) plants ha-1 for CF008; 8.25×104 (low), 9.75×104 (medium), and 11.25×104 (high) plants ha-1 for Zhengdan 958; and 6.75×104 (low), 8.25×104 (medium), and 9.75×104 (high) plants ha-1 for Jinhai 5. The high-yielding canopy structure and photosynthesis were obtained under both low and medium densities of the three cultivars. Percent transmission, leaf angle, and stem diameter decreased with the increase of plant density. The chlorophyll relative content (SPAD) and the rate of net photosynthesis rate (Pn) were the smallest under high density because of the uneven light distribution within canopy. For CF008, SPAD value of ear leaf and the third leaf under ear decreased sharply in later growth stages. LAD and LAI values before mid-filling stage were greater under medium or high densities, while different tendency occurred in the maturity stages. Moreover, the proportion of after-silking LAD was greater under low or medium densities, showing that canopy structure was unsuitable under high density due to early senescence. For Zhengdan 958 and Jinhai 5, LAD after silking was greater than that before silking, which was benefit for high grain yield. Our results confirmed that proper planting density can establish high-yielding canopy structure and improve population photosynthesis and yield in maize. We also obtained a series quantitative criteria for high-yielding canopy structure based on the data from Wuqiao area: percent transmission of 13.4%–19.45% in silking stage and 16.19%–21.48% in mid-filling stage under low or medium densities; LAI of 5.59–6.75 in silking stage and 2.24–3.68 in maturity stage, especially highen in middle and upper leaf layers in maturity stage under low or medium densities; Pn of 33.6–43.8 μmol CO2 m-2 s-1 in middle and upper layer leaves in silking stage under low or medium densities; higher LAD after silking under low or medium densities, with 172.01–235.91 m2 d m-2 under medium density.

研究了种植密度对夏播玉米(CF008、郑单958和金海5号）冠层结构及光合特性的影响，目的是通过密度调控，构建高效冠层，发挥品种潜力，同时确立不同夏玉米品种高产高效冠层的定量化技术指标。结果表明，3个夏玉米品种均在中或低密度下（CF008为9.75和11.25万株 hm-2，郑单958为8.25和9.75万株 hm -2 ，金海5号为6.75和8.25万株 hm -2 ）构建的冠层较合理，冠层光合性能较高。冠层内透光率、叶夹角、茎粗、叶绿素相对含量（SPAD值）和净光合速率（Pn）均随着密度的增加而降低，说明高密度易造成群体内光分布不合理，导致光合性能的降低。灌浆中期前群体光合势（LAD）和叶面积指数（LAI）均表现为中或高密度条件下较高，而后为中或低密度下较高，并且吐丝后LAD所占比率为中或低密度处理显著高于高密度处理，说明高密度条件下冠层结构不合理，造成生育后期叶片提早衰老。在中或低密度下，群体穗位层透光率较大，吐丝期和灌浆中期分别为13.4%~19.45%和16.19%~21.48%；叶面积发展动态较为合理，吐丝期LAI达5.59~6.75，成熟期仍然保持在2.24~3.68，尤其中上层叶片LAI高值持续期较长；吐丝期中上层叶片Pn达到33.6~43.8 μmol CO2 m -2 s -1 ；吐丝后的群体LAD较高，特别是中密度下LAD达172.01~235.91 m2 d m-2，后期光合面积持续时间较长，更有利于玉米产量的提高。

... 同时, 增加密度引起耕层根系数量增加, 植株间对有限养分水分资源的激烈竞争使个体生长发育差, 根系活力低, 地上部叶片功能期缩短, 导致花粒期群体早衰^[3,4] ...

... 本研究结果, 不同种植密度处理下夏玉米单株叶面积从灌浆中后期开始下降, 特别是进入乳熟期后迅速下降, 并随种植密度的增加降幅加大, ZD和XD在D₃、D₄、D₅密度处理下花后30~40 d叶面积降幅达20%以上, 与前人研究结果一致^[3] ...

2012

0.0

李宗新, 陈源泉, 王庆成, 刘开昌, 高旺盛, 隋鹏. 高产栽培条件下种植密度对不同类型玉米品种根系时空分布动态的影响. 作物学报, 2012, 38: 1286-1294

Li Z

, Chen Y

, Wang Q

, Liu K

, Gao W

, Sui

Influence of planting density on root spatio-temporal distribution of different types of maize under high-yielding cultivation conditions.

Acta Agron Sin, 2012, 38: 1286-1294 (in Chinese with English abstract)

A field experiment was conducted to compare the influence of planting density onthe root spatio-temporal distribution using two types of maize cultivar (LD981, a planophile massive ear type variety, and LD818, an erectophile middle ear type variety) under high-yielding cultivation conditions. The results indicated that the total root volume (TRV), total root-absorbing area (TRAA), active-absorbing area (AAA), and total root dry weight (TRDW) of the both maize varieties increased at first and then decreased during the growing stages. From the flowing stage to the milking stage, the above parameters reached their maximum values. The number of root layers, root number, TRV, TRAA, AAA, and TRDW decreased with the increase of planting density, but the rate of decrease in LD981 was higher than that in LD818. In the horizontal distribution, 0–6, 6–12, and 12–18 cm from the stem were classified as higher, mid, and lower root density zones, respectively; in the vertical distribution, 0–20, 20–40, 40–60, and 60–80 cm below the ground surface were classified as higher, mid, lower, and thinner root density layers, respectively. In the horizontal distribution, the percentage of root dry weight in 0–6 cm soil from the stem of LD818 was higher (2.96%) than that of LD981, but lower (14.33%) in 6–18 cm soil; in the vertical distribution, the percentage of root dry weight in 0–40 cm soil below the ground surface in LD818 was lower (3.71%) than that in LD981, but higher (14.33%) in 40–80 cm soil. The results of this study suggest that the requirement in root distribution space and orientation is different among different maize varieties. LD981 posses more roots mainly distributing in lower soil layers. LD981 is more sensitive to horizontal restriction owing to higher planting density, and suitable to be planted under lower planting density condition. LD818 shows the root distribution characteristics of “vertical extension and horizontal contraction”, adapting horizontal restriction owing to higher planting density, suitably cultivating under higher planting density condition.

以平展大穗型品种鲁单981 (LD981)和紧凑中穗型品种鲁单818 (LD818)，比较研究了不同种植密度下根系时空分布动态，以期为玉米品种的选育和高产栽培提供理论依据。结果表明, 随生育进程，2个品种的根系总体积、总表面积、活跃吸收面积与总干重均呈先升后降趋势，多为开花期至乳熟期达最大。随种植密度递增，LD981和LD818的根层数与数量、总体积、总表面积、活跃吸收面积以及水平与垂直方向各分布区域的干重均呈递减趋势，LD981的递减速率明显大于LD818。生育期内，不同种植密度下LD981和LD818的根系干重水平方向0~6 cm、6~12 cm和12~18 cm分布表现为高密度区、中密度区和低密度区; 垂直方向0~20 cm、20~40 cm、40~60 cm和60~80 cm土层分别表现为高密度层、中密度层、低密度层和稀密度层; LD981水平方向0~6 cm范围根系干重所占比例比LD818的低2.96%，6~18 cm则高14.33%，垂直方向0~40 cm土层根系干重所占比例前者比后者高3.71%，40~80 cm土层则低35.97%。本研究说明不同类型玉米品种对根系伸展空间方向和大小的要求存在差异，平展大穗型品种LD981单株根量多，吸收能力强，根系分布较浅，对种植密度递增导致的水平方向空间受限制的反应更为敏感，宜适当增大株距稀植; 紧凑中穗型品种LD818单株根系呈现“横向紧缩，纵向延伸”的特点，更能适应随着种植密度递增导致的水平方向空间受限制的“拥挤”，宜适当减小株距密植。

2001

0.0

... 已有研究表明, 叶片的衰老伴随着活性氧的积累以及细胞中抗氧化酶活性的降低^[5] ...

... 叶片衰老过程是活性氧代谢失调的过程, 而SOD、POD和CAT是植物体内最重要的活性氧清除酶类^[5] ...

2012

0.0

王海燕, 高聚林, 王志刚, 孙继颖, 于晓芳, 高英波, 贾宁, 叶君, 吕佳雯. 高密度对超高产春玉米花粒期叶片衰老与根系活力的影响. 玉米科学, 2012, 20: 75-81

Wang H

, Gao J

, Wang Z

, Sun J

, Yu X

, Gao Y

, Jia

, Ye

, Lü J

Effects of high planting density on super high-yielding spring maize leaf senescence and root activity at anthesis and kernel stage.

Maize Sci, 2012, 20: 75-81

选用不同穗型、株型品种浚单20、内单314和京单28为材料, 在3种种植密度(7.5万、8.25万和9.0万株/hm2)下,比较研究花粒期冠层不同层位叶片光合性能和根层根系活力的垂直变化及其关系,明确高密度条件下超高产春玉米生育后期根冠早衰及其相关机理,探索防衰增产的调控途径.结果表明,花粒期叶片的叶面积指数(LAI)均随密度增加逐渐增大,而不同层位叶片的SPAD值、光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)和根系活力均随密度增加而降低；浚单20各性状对密度变化的反应较内单314 和京单28敏感,浚单20在高密度下子粒产量最高；灌浆期浚单20根系活力最大值出现在30～40 cm的土层,内单314和京单28最大值出现在20～30 cm的土层,浚单20根系活力下移速度比内单314和京单28快,这与后期植株叶片的SPAD值、LAI、Pn、Tr和Gs的下降有着必然联系.春玉米衰老过程中地上部与地下部密切相关,叶片衰老进程与根系活力空间下移进程一致.

... 研究发现, 种植密度与叶片衰老密切相关, 王海燕等研究表明, 玉米花粒期不同层位叶片的SPAD值、光合速率、气孔导度、蒸腾速率随密度增加而降低^[6] ...

... 增加种植密度导致玉米穗位叶保绿度、叶绿素含量下降^[7], 花粒期不同层位叶片的SPAD值和可溶性蛋白含量降低^[6,8] ...

2012

0.0

解振兴, 董志强, 兰宏亮, 高娇, 朱平, 彭畅. 磷酸胆碱合剂对不同种植密度玉米叶片衰老生理的影响. 核农学报, 2012, 26: 157-163

Xie Z

, Dong Z

, Lan H

, Gao

, Zhu

, Peng

Effect of ECK mixture treatment on maize leaf senescence under different planting densities.

J Nucl Agric Sci, 2012, 26: 157-163 (in Chinese with English abstract)

Effects of plant growth regulator ethylene-CCC-PASPK(ECK) on leaf senescence physiology and yield characters were investigated under different planting densities of Jingdan 28 and Xianyu 335 in the field condition. Results indicated that leaf stay-green degree, chlorophyll content, activities of superoxide dismutase (SOD), peroxides (POD), hydrogen peroxidase (CAT) decreased and malondialdehyde (MDA) content increased with planting density increasing. Chlorophyll content was improved by 6.57%~23.40% under plant growth regulator (RGR) treatment and the stay-green degree increased by 4.5%~13.9%. The activities of SOD, POD and CAT were enhanced while MDA content was reduced under mid and high planting densities compared with control. PGR treatment also enhanced ear-length, grain number per row and 100-kernels weight as well as maize yield. And the yield in Jingdan 28 increased by 398.3kg/hm 2 with 774.2kg/hm 2 density of Xianyu 335. Furthermore, positive correlation was found between activities of SOD, POD( r =0.660 * ), CAT, chlorophyll content and yield, while negative correlation was observed in MDA content and yield( r =-0.810 ** ). Thus, we conclude that ECK can slow maize leaf aging and oxidation.

针对东北地区低温冷凉气候区密植条件下玉米叶片早衰现象,于大田条件下,研究了不同种植密度下磷酸胆碱合剂对京单28和先玉335叶片衰老相关指标及产量性状的影响。结果表明,随种植密度增加,玉米叶片保绿度、叶绿素含量下降;超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性降低,丙二醛(MDA)含量升高。化控处理后,不同种植密度下,2个玉米品种叶绿素含量提高了6.57%~23.40%,保绿度提高了4.5%~13.9%;SOD、POD、CAT活性在中高密度条件下较对照升高了4.76%~21.64%,MDA含量较对照降低4.39%~11.82%;穗长、行粒数、百粒重和产量均较对照有所增加,京单28产量最高增加了398.3kg/hm 2 ,先玉335产量最高增加了774.2kg/hm 2 。以不同品种不同密度下的各生理指标与产量进行相关分析,结果表明除MDA含量与产量呈极显著负相关外( r =-0.810**),其余都表现出正相关,其中POD活性( r =0.660*)达到了显著水平。表明磷酸胆碱合剂可以延缓玉米叶片的衰老。

... 解振兴等^[7]研究表明, 随种植密度增加, 玉米穗位叶保绿度、叶绿素含量下降, 超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性降低, 丙二醛(MDA)含量升高 ...

... 叶片失绿速率、持绿时间和绿叶面积等可作为评价衰老进程和程度的指标^[7,28,29] ...

... 增加种植密度导致玉米穗位叶保绿度、叶绿素含量下降^[7], 花粒期不同层位叶片的SPAD值和可溶性蛋白含量降低^[6,8] ...

2008

0.0

乔宏伟, 武月莲, 王志红, 侯辉. 不同玉米群体灌浆期叶片生理特性的研究. 内蒙古民族大学学报(自然科学版), 2008, (6): 637-639

Qiao H

, Wu Y

, Wang Z

, Hou

Study on leaves physiological characteristic of different maize population at filling stage.

J Inner Mongolia Univ Nationalities (Nat Sci Edn), 2008, (6): 637-639

摘　要：在两种种植密度下，对三种株型玉米品种灌浆期叶片生理特性进行了研究．结果表明：耐密型品种中层叶片可溶性糖、可溶性蛋白和比叶重分别比对照提高20．1％、15．2％、8．1％；中间型品种的各指标也分别比对照提高17．8％，12．1％，11．8％；平展型品种的各指标分别比对照提高13．2％，11．4％，9．7％．因此，选择合理的种植密度，保证中层叶片发挥最佳生理功能是不同株型玉米品种达到高产的基础。

... 乔宏伟等^[8]研究表明, 玉米不同层次叶片的可溶性蛋白含量低密度下均高于高密度下, 而可溶性蛋白含量与植株体内生理代谢的强度密切相关^[9], 并进一步影响着叶片的功能与衰老, 以及光合产物在籽粒中的积累过程和最终的籽粒产量 ...

... 增加种植密度导致玉米穗位叶保绿度、叶绿素含量下降^[7], 花粒期不同层位叶片的SPAD值和可溶性蛋白含量降低^[6,8] ...

1997

0.0

印莉萍, 柴小清, 李丹, 张承谦, 洪剑明, 刘祥林, 赵微平. 不同小麦品种叶片衰老过程中谷氨酰胺合成酶和蛋白水解酶的活性变化. 山西师大学报, 1997, (11): 46-49

Yin L

, Chai X

, Li

, Zhang C

, Hong J

, Liu X

, Zhao W

Changes of glutamine synthesis and proteolyase in different wheat speicies during the leaves nature senescence.

J Shanxi Norm Univ, 1997, (11): 46-49 (in Chinese with English abstract)

五个不同的半矮秆小麦品种在叶片自然衰老过程中,蛋白水解酶活性、可溶性蛋白含量、全N含量等方面没有显著差异,而只有谷氨酰胺合成酶(GS)活性过早的提高与秸杆N的残留量和产量有明显的负相关性.

2013

0.0

王永军, 杨今胜, 袁翠平, 柳京国, 李登海, 董树亭. 超高产夏玉米花粒期不同部位叶片衰老与抗氧化酶特性. 作物学报, 2013, 39: 2183-2191

Wang Y

, Yang J

, Yuan C

, Liu J

, Li D

, Dong S

Characteristics of senescence and antioxidant enzyme activities in leaves at different plant parts of summer maize with the super-high yielding potential after anthesis.

Acta Agron Sin, 2013, 39: 2183-2191 (in Chinese with English abstract)

Grain yield improvement of maize ( Zea mays L.) has been evidently associated with delayed leaf senescence during the grain-filling period after anthesis. The object of this study was to explore senescence characteristics and antioxidant enzyme activities after flowering in different position leaves of summer maize with high yield record for providing references of regulating the leaf senescence and achieving the higher yield in China. A field experiment planted Denghai 661, a new hybrid with high-yielding potential, was carried out to compare the experiment of maize with high yield record (EHYR) and the maize grown in conventional farmers’ field (MCFF) in individual level from 2005 to 2007. And the parameters related to the leaf senescence, such as leaf area (LA), LA reduction, net photosynthetic rate ( P n ), soluble protein content, activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and malondialdehyde (MDA) content, were determined in this research. The grain yield of EHYR was 2.18 times greater than that of MCFF, reaching 19 349 kg ha -1 . The rapid senescence time of EHYR leaves and MCFF leaves were found at 30 and 50 days after anthesis, respectively. Therefore, the leaf senescence of EHYR was 20 days earlier than that of MCFF. At the rapid senescence stage, the leaf area reduction of EHYR was 5.7% lower than that of MCFF. During the later period of leaf senescence, the net photosynthetic rate was higher in top and middle leaves than in bottom leaves. Furthermore, the soluble protein content in leaves of EHYR was higher than that of MCFF, but the MDA content was on the contrary. At 20 days after anthesis, the SOD activities in top and middle leaves of EHYR were higher than those of MCFF, while the SOD, POD, and CAT activities in bottom leaves of EHYR were higher than those of MCFF. On the contrary, the POD and CAT activities in middle leaves of MCFF were higher than those of EHYR. Results of both correlation analysis and path analysis indicated that the leaf reduction was negatively correlated with the CAT activity significantly in EHYR, also with the SOD and POD activities significantly in MCFF, and the direct effects were higher than the indirect effects of SOD, POD, and CAT in both EHYR and MCFF. Compared with MCFF treatment, besides higher SOD and POD activities, EHYR had higher CAT activities and soluble protein content resulting in declined lipid peroxidation during grain-filling period, which caused delayed leaf senescence and leaf senescence degree. There were obvious differences at 20 days post-anthesis in maize leaf senescence physiologically. Between EHYR and MCFF suggesting that the 20–30 days after anthesis is a critical period, and all the related agronomy measures should be recommended to be taken before this phase in maize production.

为探讨超高产玉米叶源衰老特征 , 揭示其抗氧化关键酶及膜脂过氧化特性 , 为玉米衰老调控和高产栽培提供依据 , 本研究在大田条件下 , 以我国创高产纪录的夏玉米为例 , 从单株水平上对高产纪录试验 (EHYR) 和普通生产田 (MCFF) 玉米叶片衰老及抗氧化酶特性比较表明 , EHYR 产量达 19 349 kg hm -2 , 是 MCFF 的 2.28 倍。 MCFF 和 EHYR 叶片分别在开花后 30 d 和 50 d 进入速衰期 , MCFF 叶片衰老比 EHYR 提前 20 d ；速衰期 EHYR 叶面积降幅比 MCFF 低 5.7% 。 EHYR 在籽粒灌浆后期 , 中上部叶片净光合速率较高 , 可溶性蛋白含量明显高于 MCFF , 而 MDA 含量则维持较低水平。在叶片衰老过程中 , 自开花后 20 d 开始 , EHYR 上部和中部叶片 SOD 活性较高 , 下部叶片则以 SOD 、 POD 和 CAT 三者活性较高； MCFF 仅中部叶片 POD 和 CAT 活性较高。 EHYR 叶片衰老程度与 CAT 活性极显著负相关 , MCFF 叶片衰老与 SOD 和 POD 活性显著负相关 , 且二者叶片衰老进程中 SOD 、 POD 、 CAT 的直接作用大于间接作用。与 MCFF 相比 , EHYR 叶片除具较高 SOD 和 POD 活性外 , 在籽粒灌浆后期同时保持较高 CAT 活性和可溶性蛋白含量是降低膜脂过氧化程度 , 延缓叶片衰老的重要原因。开花后 20 d 是 EHYR 与 MCFF 叶片衰老出现差异的生理临界点 , 因而在此时期之前调控更有利于延缓衰老。

... 玉米籽粒产量形成阶段与叶片衰老过程同步进行, 随灌浆进程发展, 叶片逐渐衰老, 因此, 在此期间延缓叶片衰老有利于增强叶片光合功能, 获得更高产量^[10] ...

... 王永军等^[10]研究发现, 不同产量群体的不同叶位保护酶活性也存在差异, 即超高产群体叶片衰老过程中, 上部和中部叶片SOD活性较高, 下部叶片则以SOD、POD和CAT三者活性较高 ...

2012

0.0

李洪岐, 蔺海明, 梁书荣, 赵会杰, 王俊忠. 密度和种植方式对夏玉米酶活性和产量的影响. 生态学报, 2012, 32: 6584-6590

Li H

, Lin H

, Liang S

, Zhao H

, Wang J

Effects of planting densities and modes on activities of some enzymes and yield in summer maize.

Acta Ecol Sin, 2012, 32: 6584-6590 (in Chinese with English abstract)

Effects of different planting densities and modes on activities of key enzymes related to carbon-nitrogen metabolism in summer maize in two cultivars, Zhengdan 958 and Xundan 20, were studied under the condition of Northern Henan Province. The results showed that the activities of nitrate reductase (NR), glutamine synthetase (GS), sucrose phosphate synthetase (SPS) and sucrose synthetase (SS) in leaves increased first and decreased later during tasseling and silking stages. The activities of NR and GS in leaves reached the peak at silking stage, and the maximum of activities of SPS and SS in grains occurred at 15d after filling. Genotype, density and planting mode had significant effects on the activities of NR, GS in leaves and SPS, SS in grains during the later-growth period, but the interaction between them was indistinctive. The activities of NR, GS in leaves and SPS, SS in grains of Zhengdan 958 were higher than those of Xundan 20 (5.02%, 7.40%, 6.25% and 4.43% increases, respectively) during the later-growth period. Within the range of 67500-90000 plants per hm 2 , the activities of these enzymes decreased significantly with the increasing of planting density. A comparison between two planting modes indicated that activities of NR, GS in leaves and SPS, SS in grains of wide-narrow row mode were higher than those of equidistant row mode (6.23%, 9.25%, 6.87% and 2.84% increases, respectively). The yield reached highest in the test plots with 82 500 plants per hm 2 and wide-narrow row mode.

在豫北灌区的生产条件下,以郑单958和浚单20为试验材料,研究了不同密度和种植方式对夏玉米碳氮关键酶的影响。结果表明:生育后期夏玉米叶片硝酸还原酶(NR)、谷氨酰胺合成酶(GS)和籽粒蔗糖磷酸合成酶(SPS)、蔗糖合成酶(SS)活性均呈先升高后降低的变化趋势,叶片NR和GS活性峰值出现在吐丝期,籽粒SPS和SS活性峰值出现在灌浆后15d。基因型、密度和种植方式对夏玉米生育后期叶片NR、GS和籽粒SPS、SS活性均有显著影响,而3因素间总体上没有显著的互作效应。郑单958生育后期叶片NR、GS和籽粒SPS、SS活性均显著高于浚单20,分别提高5.02%、7.40%、6.25%和4.43%。在6.75-9.00万株hm 2 的范围内,随着密度的增大,夏玉米生育后期叶片NR、GS和籽粒SPS、SS活性显著降低。与60cm等行距种植方式相比,80cm-40cm宽窄行种植方式下夏玉米生育后期叶片NR、GS和籽粒SPS、SS活性均显著提高,分别提高6.23%、9.25%、6.87%和2.84%。在采用宽窄行种植、密度为8.25万株hm 2 时,产量最高。

... 虽然, 将适宜的种植密度和播种方式、行间距配置^[11]相结合, 配合分次施氮肥且适当增加花粒肥比例^[12]等栽培措施相集成^[13], 在一定程度上, 提高了玉米密植群体叶片抗氧化酶活性, 延缓了植株衰老, 在一定密度范围内, 提高了籽粒产量, 但是, 应用化学调控技术可以通过调节作物自身的内源激素平衡, 调控作物的生长发育进程, 调控作物对水分、养分的吸收同化运转, 改善作物自身对环境的适应能力, 最终可以有效改善作物的产量形成, 显著提高产量^[14,15,16] ...

2012

0.0

吕鹏, 张吉旺, 刘伟, 杨今胜, 董树亭, 刘鹏, 李登海. 施氮时期对高产夏玉米氮代谢关键酶活性及抗氧化特性的影响. 应用生态学报, 2012, 23: 1591-1598

Lü

, Zhang J

, Liu

, Yang J

, Dong S

, Liu

, Li D

Effects of nitrogen application period on the nitrogen metabolism key enzymes activities and antioxidant characteristics of high-yielding summer maize.

Chin J Appl Ecol, 2012, 23: 1591-1598 (in Chinese with English abstract)

Taking the high-yielding summer maize cultivars Denghai 661 (DH661) and Zhengdan 958 (ZD958) as test materials, a field experiment was conducted to study their grain yield, nitrogen use efficiency, key enzymes activities of nitrogen metabolism, and antioxidant enzymes activities under effects of different nitrogen application periods. One-dose nitrogen application at jointing stage was not beneficial to the increase of grain yield and the nitrogen accumulation in plant and grain, while split application in combination with application after anthesis increased the nitrogen accumulation in plant and grain significantly and increased the grain yield. When the nitrogen was applied at a ratio of 2：4：4 at jointing stage, 10-leaf stage, and 10 days after anthesis, the grain yield of DH661 was up to 14123.0 kg·hm -2 ; when the nitrogen was applied at a ratio of 1：2：5：2 as the basal and at jointing stage, 10-leaf stage, and 10 days after anthesis, the grain yield of ZD958 was up to 14517.1 kg·hm -2 . These two nitrogen application modes increased the grain yield of DH661 and ZD958 by 14.5% and 17.5%, respectively, as compared with onedose nitrogen application at jointing stage. Split nitrogen application before anthesis increased plant nitrate reductase activity significantly. In the 0-42 days after anthesis under split nitrogen application, the glutamine synthetase, glutamate synthase, and glutamate dehydrogenase activities of DH661 and ZD958 were averagely increased by 32.6%, 47.1% and 50.4%, and 14.5%, 61.8% and 25.6%, and the superoxide dismutase and catalase activities were increased by 22.0% and 36.6%, and 13.4% and 62.0%, respectively, and the malondialdehyde content was decreased significantly, as compared with oneoff nitrogen application. It was suggested that for the high-yielding of summer maize, split application of nitrogen and appropriately increasing the nitrogen application ratio after anthesis could enhance the plant key nitrogen metabolism enzymes activities, delay leaf senescence, promote plant nitrogen uptake and its utilization, and increase grain yield.

选用玉米品种登海661和郑单958为材料，研究了高产条件下施氮时期对夏玉米产量、氮素利用率、氮代谢相关酶及抗氧化酶活性的影响.结果表明：拔节期一次性施氮不利于夏玉米产量提高和氮素积累，分次施氮且增施花粒肥显著提高了植株和籽粒的吸氮量，并提高了籽粒产量.拔节期、10叶期、花后10 d按2∶4∶4施氮，登海661产量最高可达14123.0 kg·hm -2 ；基肥、拔节期、10叶期、花后10 d按1∶2∶5∶2施氮，郑单958产量最高可达14517.1 kg·hm -2 ，这2种施氮方式较拔节期一次性施氮分别增产14.5%和17.5%.花前分次施氮可以显著提高开花期硝酸还原酶活性；登海661和郑单958在花后0~42 d中，施氮处理的谷氨酰胺合成酶、谷氨酸合成酶、谷氨酸脱氢酶活性分别平均提高了32.6%、47.1%、50.4%和145%、61.8%、25.6%，减缓了其下降趋势；超氧化物歧化酶、过氧化氢酶活性提高了22.0%、36.6%和13.4%、62.0%，丙二醛含量显著降低.在高产条件下，分次施氮且适当增加花粒肥施入比例可以提高氮代谢相关酶活性，延缓植株衰老，促进氮素吸收利用，进而提高籽粒产量.

... 水分、温度和养分亏缺等逆境胁迫条件以及增加种植密度, 均导致玉米叶片的保护酶活性提高, 从而有效减轻膜脂过氧化程度^[12,14,30] ...

2014

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朱昆仑, 靳立斌, 董树亭, 赵斌, 刘鹏, 张吉旺. 综合农艺管理对夏玉米叶片衰老特性的影响. 中国农业科学, 2014, 47: 2949-2959

Zhu K

, Jin L

, Dong S

, Zhao

, Liu

, Zhang J

Effects of integrated agronomic practices on leaf senescence physiological characteristics of summer maize.

Sci Agric Sin, 2014, 47: 2949-2959

【Objective】This study is to explore the effects of integrated agronomic practices on leaf senescence physiological characters of summer maize. 【Method】 Zhengdan958 was used as experimental material, integrated agronomic managements experiment (MT), including 4 treatments of T1, T2, T3 and T4, and nitrogen rate experiment (0, 129.0, 184.5, 300.0 kg N hm-2, signed by N0, N1, N2, N3) which was based on T4 treatment were designed to explore the effects of integrated agronomic practices and nitrogen rate on leaf area index (LAI), photosynthetic pigments content, superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities and malondialdehyde (MDA) content in ear leaves of summer maize through the optimal combinations of planting methods, sowing and harvest date, as well as nitrogen fertilizer application timing and rate. 【Result】 LAI of T4 was always above 4.4 from V12 to 42 days after tasseling (VT), which was significantly higher than those of T1 and T2, and the LAI reduction of T4 was slower in later growing period. As for nitrogen rate treatments (NT), the LAI was increased with the increasing of nitrogen rate. The LAI of N3 decreased by 14.9% from 28 days after VT to R6 which was higher than those of the other treatments. As for MT and NT, the photosynthetic pigments content got the maximum value on 14 day after VT and then decreased, following the change of unimodal curve. From 14 days after VT to 42 days after VT, the chlorophyll (a+b) content of T1, T2, T3, T4 decreased by 21.1%, 22.0%, 27.2% and 18.4% and the carotenoid content of T1, T2, T3, T4 decreased by 26.6%, 26.9%, 32.2% and 25.0%, respectively. On 42 day after VT, the content of chlorophyll a, chlorophyll b, chlorophyll (a+b) and carotenoid in T4 were increased by 6.0%, 13.0%, 6.9%, 9.3% compared to T1, respectively. As for NT, the content of chlorophyll a, chlorophyll b and chlorophyll (a+b) increased significantly with the increasing of nitrogen rate. The carotenoid content of N3 decreased rapidly in latter growing period, and which was decreased by 4.5% compared to that of N0 on 42 day after VT. In MT and NT, the activities of SOD, CAT and POD got the maximum value on 14 day after VT and then decreased, following the change of unimodal curve. The SOD, CAT and POD activities of T4 always remained at high levels and its decreasing was lower in the latter growing period. In NT, SOD, CAT and POD activities were increased as the increasing of nitrogen rate, the protective enzymes activity of N3 decreased faster than those of the other treatments. In MT and NT, MDA content increased following the growth process, and decreased with the increasing of nitrogen rate. MDA content of T4 always remained at low levels. 【Conclusion】 When the nitrogen rate was higher than 184.5 kg•hm-2, photosynthetic pigments content and protective enzymes activity of leaves couldn’t be increased and MDA content couldn’t be decreased continuously with the increasing of nitrogen rate, which was not helpful to increase nitrogen use efficiency. By increasing plant density, changing relay intercropping to direct seeding, and delaying sowing and harvesting date, as well as optimizing nitrogen fertilizer application timing and rate, photosynthetic pigment content of ear leaves in T4 decreased slower, protective enzymes activity were higher, and MDA content was lower, which was helpful to improve both grain yield and nitrogen use efficiency together.

【目的】研究综合农艺管理对夏玉米叶片衰老特性的影响。【方法】以郑单958为试验材料，对播期、播种方式、密度、氮肥施用时期及用量和收获时间等农艺措施进行优化组合，设置综合农艺管理试验，共4个处理：按当地农户习惯即麦田后期套种玉米、苗期一次性施氮和苞叶变白、籽粒变硬时收获等设置为处理1（T1）；在此基础上改套种为直播，减少氮肥施用量，优化施肥时期，延迟收获时间，设置为处理2（T2）；在T2的基础上进一步提高施肥量，增加磷、钾肥比例，将氮肥分次施用，增加种植密度，以期达到最高产量，设置为处理3（T3）；在T3的基础上减少施肥量，进一步优化施肥时期，适当降低种植密度，设置为处理4（T4）。然后以T4处理为基础设置单因素施氮量试验（0、129.0、184.5和300.0 kg N•hm-2，分别记作N0、N1、N2和N3），研究综合农艺管理和施氮量对夏玉米叶面积指数、叶片光合色素含量、超氧化物歧化酶（SOD）活性、过氧化氢酶（CAT）活性、过氧化物酶（POD）活性和丙二醛（MDA）含量的影响。【结果】从大喇叭口期（V12）到抽雄后42 d，T4处理的LAI平均维持在4.4以上，显著高于T1和T2处理，且后期下降缓慢。在施氮量试验中，LAI随施氮量的增加而增加，从抽雄后28 d到成熟期（R6），N3的LAI平均下降了14.9%，高于其他施氮处理的降幅。综合农艺管理试验（MT）和施氮量试验（NT）的叶片光合色素含量均呈单峰曲线变化，在抽雄后14 d达到最大值，之后逐渐下降，从抽雄后14—42 d，T1、T2、T3和T4处理叶绿素（a+b）的含量分别减少了21.1%、22.0%、27.2%和18.4%，类胡萝卜素含量分别减少了26.6%、26.9%、32.2%和25.0%。抽雄后42 d，T4的叶绿素a、叶绿素b、叶绿素（a+b）和类胡萝卜素含量分别较T1提高了6.0%、13.0%、6.9%和9.3%。NT试验中叶绿素a、叶绿素b和叶绿素（a+b）的含量随施氮量的增加而增加；N3处理的类胡萝卜素含量生育后期急剧下降，到抽雄后42 d，N3处理的类胡萝卜素含量较N0降低4.5%。MT和NT试验各处理穗位叶的SOD、CAT和POD活性均呈单峰曲线变化，在抽雄后14 d达到最大值，之后逐渐下降，T4处理的SOD、CAT和POD活性始终维持在较高水平且后期下降缓慢；NT试验中随施氮量增加，SOD、CAT和POD活性增加，但是，与N2处理相比较，N3 的LAI和叶片的SOD活性、CAT活性等未全部随施氮量增加而显著增加，且N3处理生育后期叶片保护酶活性下降快于其他施氮处理。随生育进程的推进，MT和NT处理穗位叶的MDA含量均呈上升趋势，T4处理始终维持在较低水平，增施氮肥叶片MDA含量逐渐降低。【结论】在75 000株/hm2种植密度条件下，当施氮量超过184.5 kg•hm-2后，继续单一增施氮肥不能持续增加保护酶活性，减少MDA含量，且导致保护酶活性下降加快，MDA含量增加变快，不利于氮素的高效利用。通过改麦套为麦收后直播、适当增加种植密度、分次合理施氮和适期收获等综合农艺措施优化可提高叶片光合色素含量且生育后期降低缓慢，叶片保护酶活性较高，MDA含量维持较低水平，这可能是其产量和氮素效率提高的原因。

2012

0.0

徐田军, 董志强, 高娇, 陈传晓, 焦浏, 解振兴. 聚糠萘水剂对不同积温带玉米叶片衰老和籽粒灌浆速率的影响. 作物学报, 2012, 38: 1698-1709

Xu T

, Dong Z

, Gao

, Chen C

, Jiao

, Xie Z

Effect of PASP-KT-NAA on leaf senescence and grain filling rate during the grain-filling period in different temperature zones.

Acta Agron Sin, 2012, 38: 1698-1709 (in Chinese with English abstract)

Field experiment was performed to investigate the effects of the chemical regulation of PASP-KT-NAA (PKN) on leaf senescence physiology and grain filling rate under different temperatures. The result showed that the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), chlorophyll concentration in ear leaves of two maize cultivars were declined, while malondialdehyde (MDA) content increased in three accumulate temperature zones with low temperature. In the same accumulated temperature zone, and in process of growth, SOD, POD, CAT activities showed the trend of a single peak curve with “first increase and then decrease”, and MDA content showed an opposite trend. PKN treatment increased SOD, POD, CAT activities and chlorophyll contents of ear leaves, while declined MDA content in ear leaves of Zhengdan 958 and Fengdan 3. From the first accumulated temperature zone to the third accumulated temperature zone, the grain weight of two maize cultivars show a S-shape increase in the “low-fast-low” type and the grain filling rate showed an “increased and then declined” trend. The grain weight and the grain filling rate of the first accumulated temperature zone were higher than those of the second and the third accumulated temperature zones. PKN treatment had higher grain weight and the grain filling rate compared with the control. In 2010 and 2011, the yield of two varieties of maize increased in the PKN treatment. The yield of Zhengdan 958 and Fengdan 3 in the third accumulated temperature zone was 2.58%, 1.17% and 2.04%, 1.48% higher than that in the first and second accumulated temperature zones, in 2010 and 8.2%, 5.1% and 3.4%, 0.8% higher than that in the first and second accumulated temperature zones in 2011. Thus, the chemical regulation in proved to have contributions to delaying the leaf senescence, improving the grain filling rate, and ultimately increasing the yield in maize.

在大田栽培条件下，以郑单958和丰单3号为材料，于六叶期喷施玉米专用抗冷剂聚糠萘水剂(PKN)，研究PKN对黑龙江省3个积温带上花后玉米穗位叶衰老生理及籽粒灌浆速率的影响。结果表明，从第I积温带到第III积温带，气温逐渐降低; 两玉米品种穗位叶的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性及叶绿素(Chl a+Chl b)含量均呈逐渐下降趋势，而MDA含量呈逐渐升高的趋势。同一积温带，两品种不同处理的穗位叶SOD、POD、CAT的活性随生育期呈“先升高后下降”的单峰变化趋势，而MDA含量呈“先降低后升高”的趋势; PKN处理后3个积温带的两品种穗位叶SOD、POD、CAT的活性及叶绿素含量较对照均有不同程度的提高。而MDA的含量与对照相比呈下降趋势。从第I积温带到第III积温带，两品种籽粒的干重均随籽粒的发育呈“慢—快—慢”的S型变化，而灌浆速率呈“先升高后降低”的单峰曲线变化趋势，且两品种籽粒干物重和灌浆速率呈下降趋势; PKN处理后两品种的籽粒干物重和灌浆速率较对照均有不同程度的提高。2010年和2011年PKN处理后3个积温带两品种的产量均增加。2010年第III积温带的ZDTR和FDTR的增产幅度比第I、第II积温带高2.58%、1.17%和2.04%、1.48%。2011年第III积温带的ZDTR和FDTR的增产幅度比第I、第II积温带高8.2%、5.1%和3.4%、0.8%。由此可见，PKN处理后延缓玉米叶片衰老，提高籽粒的灌浆速率，最终增加玉米的产量。

... 水分、温度和养分亏缺等逆境胁迫条件以及增加种植密度, 均导致玉米叶片的保护酶活性提高, 从而有效减轻膜脂过氧化程度^[12,14,30] ...

2014

0.0

高娇, 董志强, 徐田军, 陈传晓, 焦浏, 卢霖, 董学瑞. 聚糠萘水剂对不同积温带玉米花后叶片氮同化的影响. 生态学报, 2014, 34: 2938-2947

Gao

, Dong Z

, Xu T

, Chen C

, Jiao

, Lu

, Dong X

Effects of PASP-KT-NAA on maize leaf nitrogen assimilation after florescence over different temperature gradients.

Acta Ecol Sin, 2014, 34: 2938-2947 (in Chinese with English abstract)

Northeast China is a key area for maize production, but the low temperatures often result in delayed maize growth and slow maturity, as well as low grain quality and high grain moisture. So, to help improve maize yield, we studied the effects of PASP-KT-NAA on maize leaf nitrogen assimilation characteristics after florescence over different accumulated temperature regions with Zhengdan 958 and Fengdan 3 maize seeds as materials, in Heilongjiang province. The protein content in maize leaves is low and the key enzyme activities of nitrogen metabolism are susceptible to changes in environment, such as frost harm, etc. For this reason, the effects of different temperatures and the PASP-KT-NAA mixture on maize NRA (nitrogen reductive activity) in leaf tissue has been studied in three different accumulated temperature zones in Heilongjiang province, during 2010-2011. In field experiments, the first zone trial plot is located in the science station of Heilongjiang academy of agriculture sciences in Harbin. Its general accumulated temperature is ≥2800℃, but the accumulated temperature in the maize growing season in 2010 and 2011 is 3154.2℃ and 3004.2℃, respectively. The second zone trial plot is located in the science station of Heilongjiang Academy of Agricultural Sciences in Suihua City. Its general accumulated temperature is ≥2600℃, but the accumulated temperature in the maize growing season in 2010 and 2011 is 2901.8℃ and 2885.0℃, respectively. The third zone trial plot is located in Yi'an County. Its general accumulated temperature is ≥2400℃, but the accumulated temperature in the maize growing season in 2010 and 2011 is 2728.3℃ and 2602.6℃, respectively. The results showed that: (1) The NRA, NO 3 - content, leaf nitrogen content and chlorophyll content were affected by temperature, in zone order of I > Ⅱ > Ⅲ. After PKN treatment, FDTR and ZDTR ear leaf NRA in the three accumulated temperature zone were significantly higher than that in the water control and leaf nitrogen content and chlorophyll content was higher than the water control. The average of the ear leaf free amino acid of the two maize varieties performed "up-down" trends with the growth process, and reached its maximum 20 d after florescence. The soluble protein of zone Ⅰ tended to decrease with the growth process, with zones Ⅱ, and Ⅲ firstly increasing then decreasing with the growth process, reaching its maximum at 10 d after florescence. After PKN treatment, ear leaf free amino acid and soluble protein in samples from zone Ⅰ, Ⅱ and Ⅲ were significantly higher than the water control; (2) The grain yield of zone Ⅰ was higher than that for zone Ⅱ and Ⅲ. PKN treatment raised grain yield higher than those of the water control. The increased rate of ZDTR yield in zones Ⅰ, Ⅱ and Ⅲ in 2010 and 2011 were 3.09%-8.81%, 4.61%-10.91%, 5.91%-13.51%, respectively. The increased rate of FDTR yield in zones Ⅰ, Ⅱ and Ⅲ, in 2010 and 2011 were 2.43%-5.19%, 3.03%-6.01%, 2.57%-4.62%, respectively. PKN treatment improved the maize ear leaf nitrogen assimilation key enzyme activity and its product content over different accumulated temperature regions, promoted nitrogen assimilation normally under low temperature conditions and eventually increased yield.

试验于2010-2011年在黑龙江省3个积温带哈尔滨市（Ⅰ）、绥化市（Ⅱ）、依安县（Ⅲ）的试验站进行，以郑单958和丰单3号为材料，研究大田条件下温度差异对花后玉米穗位叶氮同化及产量的影响与化学调控剂——聚糠萘水剂（PASP-KT-NAA， PKN）的调控效应。结果表明：（1）硝酸还原酶活性（Nitrate Reductase Activity， NRA）、硝态氮、叶绿素、叶片氮含量表现为Ⅰ > Ⅱ > Ⅲ；可溶性蛋白与游离氨基酸含量花后0-10 d表现为Ⅲ高于Ⅰ、Ⅱ；在花后30-40 d 游离氨基酸Ⅰ高于Ⅱ、Ⅲ；PKN处理提高NRA、硝态氮、叶绿素、叶片氮含量、可溶性蛋白和游离氨基酸含量。（2）玉米产量均表现为Ⅰ > Ⅱ > Ⅲ，郑单958产量均高于丰单3号；PKN处理后，玉米产量均高于清水对照，其中郑单958化控处理（Zhengdan treatment， ZDTR）在Ⅰ、Ⅱ、Ⅲ的增产幅度分别为为3.09%-8.81%，4.61%-10.91%，5.91%-13.51%；丰单3号化控处理（Fengdan treatment， FDTR）在Ⅰ、Ⅱ、Ⅲ的增产幅度为2.43%-5.19%，3.03%-6.01%，2.57%-4.62%。PKN处理提高了3个积温带玉米穗位叶片氮同化关键酶活及其产物含量，促进低温条件下氮同化正常进行，最终提高产量。

2014

0.0

杨东清, 李玉玲, 倪英丽, 尹燕枰, 崔正勇, 张永太, 马仁元, 王振林. 外源ABA和6-BA对不同持绿型小麦籽粒灌浆进程及蛋白质含量影响. 作物学报, 2014, 40: 301-312

Yang D

, Li Y

, Ni Y

, Yin Y

, Cui Z

, Zhang Y

, Ma R

, Wang Z

Effects of exogenous ABA and 6-BA on protein content and grain filling process in different types of stay green wheat.

Acta Agron Sin, 2014, 40: 301-312 (in Chinese with English abstract)

This study aimed to understand the grain filling process and protein biosynthesis in grain of stay-green wheat in response to exogenous hormones. At blooming stage, plants of Wennong 6 (stay-green cultivar) and Jimai 20 (control) were sprayed with 10 mg L - 1 abscisic acid (ABA) and 6-benzyladenine (6-BA) for four days.Compared with Jimai 20, Wennong 6 had longer grain-filling duration (t 3 ) and the active growth phase ( D ), higher mean grain-filling rate ( G mean ) and maximum grain-filling rate ( G max ), larger thousand-grain weight (TGW), and greater grain yield (GY). All parameters for grain filling were higher in superior grain than in inferior grain. G mean , G max , TGW, and GY were promoted by ABA or 6-BA treatment in both cultivars. However, the effects of exogenous hormones on t 3 and D were interacted with grain position in a panicle and genotype. Exogenous ABA and 6-BA treatment obviously increased protein content at 35 days after anthesis (DAA). The glutenin contents in ABA-treated and 6-BA-treated Wennong 6 significantly increased at 35 DAA; however, those in Jimai 20 decreased at 35 DAA. Exogenous ABA increased endogenous zeatin (ZR) content from 7 DAA to 21 DAA. In Wennong 6, GA 3 content in superior grain was significantly decreased from 7 DAA to 21 DAA by 6-BA treatment, however, its content in inferior grain was enhanced. In both cultivars, application of ABA and 6-BA resulted in significant increases of endogenous auxin (IAA) and ABA contents from 7 DAA to 21 DAA, along with significant enhancement of glutamine synthetase (GS) activity.

本文旨在揭示持绿型小麦品种的灌浆特性和籽粒蛋白质含量对外源激素的响应，认识植物激素调控籽粒灌浆和蛋白质合成的作用机制。自盛花期开始，连续 4 d 喷施 10 mg L - 1 脱落酸 (ABA) 和 6- 苄基腺嘌呤 (6-BA) ，持绿型品种汶农 6 号的灌浆期 (t 3 ) 、活跃生长期 ( D ) 、平均灌浆速率 ( G mean ) 、最大灌浆速率 ( G max ) 、千粒重 (TGW) 和产量 (GY) 均大于非持绿型济麦 20 ，且强势粒的各项灌浆参数均大于弱势粒。喷施两种外源激素显著提高两品种的 G mean 、 G max 、 TGW 和 GY ，对 t 3 和 D 的影响存在粒位及品种效应。喷施 ABA 和 6-BA 均显著提高花后 35 d 的籽粒蛋白质含量，显著提高汶农 6 号强、弱势粒的麦谷蛋白含量，但济麦 20 强、弱势粒的麦谷蛋白含量显著降低。喷施 ABA 后，汶农 6 号强势粒花后 7~21 d 的玉米素核苷 (ZR) 含量显著升高；喷施 6-BA 后，济麦 20 弱势粒花后 14~35 d 的 ZR 含量显著升高，而汶农 6 号强势粒 7~21 d 的赤霉素 (GA 3 ) 含量显著降低，弱势粒花后 7~28 d 的 GA 3 含量显著提高。喷施外源 ABA 和 6-BA 显著提高两品种强势粒花后 7~21 d 的生长素 (IAA) 和 ABA 含量。 ABA 和 6-BA 处理显著提高花后 7~21 d 谷氨酰胺合成酶 (GS) 活性。可见，喷施外源 ABA 和 6-BA 使小麦内源激素水平变化，促进籽粒灌浆，增加粒重和产量，提高籽粒 GS 活性和蛋白质含量，改变蛋白质组分。

2010

0.0

... 研究表明, 外施矮壮素可以提高作物保护酶活性和可溶性蛋白含量, 进而提高作物的抗逆性^[17,18] ...

... 第一, ECK主成分之一矮壮素能够提高作物抗氧化系统酶活性和可溶性蛋白含量, 降低活性氧产生速率, 保持膜完整性, 提高抗逆性^[17,18], 主成分之二乙烯利可以促进根系生长, 并调控株型结构, 增加玉米产量^[19,20] ...

2009

0.0

冯斗, 张涛, 禤维言, 胡蔚东. 3种生长延缓剂对甜高粱幼苗生长和生理特性的影响. 热带作物学报, 2009, 30: 1468-1472

Feng

, Zhang

, Xuan W

, Hu W

Effects of three retardants on growth and physiological properties of sweet sorghum seedlings.

Chin J Trop Crops, 2009, 30: 1468-1472 (in Chinese with English abstract)

Seeds of sweet sorghum［Sorghum hicolor (L.) Moench］ were soaked with 3 growth retardants, Paclobutrazol, CCC and Daminozide, at different concentrations for 24 h to observe the growth of sweet sorghum seedlings. Results showed that Paclobutrazol had the highest inhibitory effect on the growth of the seedlings among all the retardants. The sweet sorghum seeds treated with Paclobutrazol at 0.1l～0.2 g/L had a higher germination vigor and rate, but the growth of the sweet sorghum seedlings was highly inhibited and showed abnormality. The treatments with 5 g/L or 10 g/L of CCC and Daminozide retarded the growth of the sweet sorghum seedlings, shortened and thicken their leaves, increased leaf contents of chlorophyll and soluble sugars and protein in sweet sorghum seedlings, and improved synthesis and accumulation of dry matter of the seedlings. These 2 retardants were good for raising strong seedlings, of which the CCC treatment at 10 g/L was found the best for improving growth and physiological property of sweet sorghum seedlings.

采用不同浓度的多效唑、矮壮素、比久对甜高粱种子进行浸种处理，结果表明，3种生长延缓剂中，多效唑对甜高粱幼苗生长的抑制作用最强；0.1～0.2 g/L的多效唑浸种处理可以提高种子的发芽势和发芽率，但幼苗生长受到过度抑制而表现不正常；5 g/L和10 g/L的矮壮素和比九处理可以延缓甜高粱幼苗生长，使叶片缩短、厚度增加，具有提高幼苗可溶性糖、可溶性蛋白质和叶绿素含量的作用，促进了幼苗对干物质的合成和积累，使幼苗干物质重显著提高，有利于培育壮苗。其中，10 g/L矮壮素浸种处理效果最佳。

... 研究表明, 外施矮壮素可以提高作物保护酶活性和可溶性蛋白含量, 进而提高作物的抗逆性^[17,18] ...

2008

0.0

葛建军, 朱林, 张国良, 韩文节, 殷玉宏, 李勇. 乙烯利对花生氮代谢和光合特性的影响. 花生学报, 2008, 37: 22-27

Ge J

, Zhu

, Zhang G

, Han W

, Yin Y

, Li

Effects of ethephon on nitrogen metabolism and photosynthesis characters of peanut.

J Peanut Sci, 2008, 37: 22-27 (in Chinese with English abstract)

采用田间小区试验探讨了不同乙烯利浓度对花生氮代谢和光合特性的调控效果.试验结果表明,不同浓度的乙烯利能够明显提高花生功能叶叶绿素含量和光合速率,有利于功能叶光合产物的合成和累积以及籽粒产量和品质的提高;有利于花生功能叶中的氮素向籽粒等库的转运,不同浓度的各处理功能叶中全氮、蛋白氮含量的减少量均高于对照;且能够明显提高花生结荚前期功能叶硝酸还原酶、谷氨酰胺合成酶和转化酶活性及结荚中、后期功能叶中蛋白水解酶活性;能明显提高花生籽粒全氮、蛋白氮的含量,且以150 mg/L浓度最合理.

... 适宜浓度的乙烯利可以促进根系生长, 并调控株型结构, 增加玉米产量^[19,20] ...

2011

0.0

卫晓轶, 张明才, 李召虎, 段留生. 不同基因型玉米对乙烯利调控反应敏感性的差异. 作物学报, 2011, 37: 1819-1827

Wei X

, Zhang M

, Li Z

, Duan L

Differences in responding sensitivity to ethephon among different maize genotypes.

Acta Agron Sin, 2011, 37: 1819-1827 (in Chinese with English abstract)

Lodging is one of the key limiting factors causing serious yield decline in maize cultivation, the plant growth regulator ethephon and its complex formulation are applied to improve quality and lodging-resistance ability of stalks, which is an effective way to prevent stalk lodging . The responses in plant-type, physiological and biochemical characteristics of maize hybrid Nongda 108, Ludan 981 and their corresponding parents Xu 178, Huang-C, Qi 319, and lx9801 varieties, were studied in field condition, with 200 mg L -1 ethephon foliage spray at jointing stage. The results showed that ethephon significantly inhibited the elongation of the first to sixth basal internodes for Nongda 108 and Ludan 981, the plant height and the ear height of Nongda 108 and Ludan 981 were significantly reduced. Ethephon remarkably increased the activities of phenylalanine ammonia lyase (PAL) and indole acetic acid oxidase (IAAO) and content of abscisic acid (ABA) in elongating internodes, and decreased contents of auxin (IAA) and gibberellin (GA 4 ). The genetic traits were analyzed, the plant height and the ear height of Xu 178, Huang-C, Qi 319, and lx9801 were significantly reduced after ethephon treating, and the length of basal internodes was shortened significantly. The PAL and IAAO activities in elongating internodes were significantly increased after ethephon treating. The endogenous IAA content of elongating internodes was significantly decreased, ABA content was significantly increased, but GA 4 /ABA ratio was significantly decreased. It is indicated that the response differences to ethephon among different hybrids may be attributed to the different sensitivities of the parents lines, showing corresponding performance in plant height , ear height, PAL, IAAO activities and endogenous hormone levels.

倒伏是玉米高产栽培中导致产量严重下降的关键性限制因素之一，应用植物生长调节剂乙烯利或复配剂改善玉米茎秆质量、提高抗倒能力，是解决玉米倒伏的有效途径。本研究以玉米杂交种农大108、鲁单981及其相应亲本许178、黄C、齐319和lx9801为材料，在拔节期叶面喷施200 mg L -1 乙烯利药液，研究了乙烯利对不同基因型玉米株型及其生理生化特征的影响。结果表明，乙烯利处理显著降低了农大108、鲁单981的株高和穗位高，特别是显著抑制了基部第1至6节间伸长；乙烯利处理显著提高了基部伸长节间中的苯丙氨酸解氨酶(PAL)和吲哚乙酸氧化酶(IAAO)活性，降低了基部伸长节间中生长素(IAA)和赤霉素(GA 4 )含量，增加了脱落酸(ABA)的积累。乙烯利处理显著降低了亲本许178、黄C、齐319和lx9801的株高和穗位高，显著缩短了基部节间长度；乙烯利处理后显著提高了基部伸长节间PAL和IAAO活性，显著降低了节间IAA和GA 4 含量，提高了脱落酸含量，降低了GA 4 /ABA比值。结合植株性状和生理生化特征分析，杂交种对乙烯利调控反应敏感性差异是由其双亲对乙烯利反应差异造成的，表现在乙烯利处理父母本间株高、穗位高、PAL和IAAO活性以及内源激素含量变化上存在显著差异。

... 适宜浓度的乙烯利可以促进根系生长, 并调控株型结构, 增加玉米产量^[19,20] ...

2009

0.0

薛金涛, 张保明, 董志强, 赵明, 黄长玲. 化学调控对玉米抗倒性及产量的影响. 玉米科学, 2009, 17: 91-98

Xue J

, Zhang B

, Dong Z

, Zhao

, Huang C

Effects of chemical regulation on lodging and yield of maize.

J Maize Sci, 2009, 17: 91-98 (in Chinese with English abstract)

以高秆大穗型品种中单808为试验材料,研究不同种植密度下化学调控对玉米植株抗倒性及产量的影响.结果表明,在60000株/hm2的密度下不发生倒伏;超过75 000株/hm2发生倒伏,倒伏率随种植密度的增加而增加.化学调控显著提高了玉米的抗倒伏能力,与对照相比,化学调控处理降低了拔节期至抽雄期玉米的株高,增加了地上部第3节间的粗度,显著增强了茎秆的抗拉弯强度和穿刺强度,降低了倒伏率.在密度为75 000株/hm2以上时,化学调控处理显著增加了玉米的产量.

... 3, 含量为28%)应用面积较大, 在密植群体矮化株高、抗倒伏等方面效果显著^[21,22], 但是, 上述研究均限于夏玉米生育前期, 即六展叶期处理对株型建构、茎秆质量形成和根系建构等方面的影响, 而有关乙矮合剂对生育后期(花粒期— ...

... 第二, ECK处理能够改善玉米密植群体的株型结构, 提高茎秆抗倒伏能力, 提高耐密性, 使其更适于密植^[21,22] ...

2015

0.0

卢霖, 董志强, 董雪瑞, 焦浏, 李光彦, 高娇. 乙矮合剂对不同密度夏玉米茎秆抗倒伏能力及产量的影响. 作物杂志, 2015, (2): 70-77

, Dong Z

, Dong X

, Jiao

, Li G

, Gao

Effects of Ethylene-Chlormequat-Potassiumon stem lodging-resistance and yield of summer maize under different sowing densities.

Crops, 2015, (2): 70-77 (in Chinese with English abstract)

以中单909和浚单20为试验材料,研究乙矮合剂对不同密度夏玉米茎秆形态建成、抗折力、抗倒伏指数及产量的影响。结果表明,随密度增加,株高、穗位高、重心高度、节间长度、倒伏率呈升高趋势,而节间粗度、单位长度节间干重、抗折力及抗倒伏指数呈降低趋势,这些变化品种间存在差异。乙矮合剂处理显著降低株高、穗位高、重心高度,缩短节间长度、增加节间直径和单位长度节间干重,抗折力和抗倒伏指数提高,倒伏率降低;较高密度下(≥7.5万株/hm2),中单909和浚单20较各自对照增产幅度分别为3.77%~8.15%和6.73%~68.94%。综上所述,采用合理的种植密度并结合喷施乙矮合剂,能够提高抗倒伏能力和产量,可作为华北夏玉米区高产栽培的重要技术措施。

... 第二, ECK处理能够改善玉米密植群体的株型结构, 提高茎秆抗倒伏能力, 提高耐密性, 使其更适于密植^[21,22] ...

1978

0.0

... 参考Tollenaar等^[23]方法, 用2次测得的绿叶面积相对减少的比例来描述叶片衰老程度, 即LA降幅(%) = (LAt2 - LAt1)/ LAt1 × ...

2002

0.0

... L, 加入考马斯亮蓝G-250溶液3 mL, 混匀, 在室温下静置2 min, 595 nm处比色^[24] ...

1990

0.0

王爱国, 罗广华. 植物的超氧物自由基与羟胺反应的定量关系. 植物生理学通讯, 1990, (6): 55-57

Wang A

, Luo G

Quantitative relation between the reaction of hydroxylamine and superoxide anion radicals in plants.

Plant Physiol Commun, 1990, (6): 55-57 (in Chinese)

摘　要：

... 参照王爱国等^[25]的方法测定SOD活性, 吸取20 μ ...

2002

0.0

李忠光, 李江鸿, 杜朝昆, 黄号栋, 龚明. 在单一提取系统中同时测定五种植物抗氧化酶. 云南师范大学学报(自然科学版), 2002, 22(6): 44-48

Li Z

, Li J

, Du C

, Huang H

, Gong

Simultaneous measurement of five antioxidant enzyme activities using a single extraction system.

J Yunnan Norm Univ (Nat Sci Edn), 2002, 22(6): 44-48 (in Chinese with English abstract)

摘　要：文章介绍了在一个单一酶提取系统中同时提取并测定五种抗氧化酶.通过对酶测定反应的动力学分析,确定了各个酶测定的适宜参数.这一提取和测定系统使多种抗氧化酶的提取变得简便快速,并使酶活性测定结果有较好的准确性、重复性和可比性.

... 参照李忠光等^[26]的方法测定POD活性, 吸取20 μ ...

1984

0.0

林植芳, 李双顺, 林桂珠, 孙谷畴, 郭俊彦. 水稻叶片的衰老与超氧物歧化酶活性及脂质过氧化作用的关系. 植物学报, 1984, 26: 605-615

Lin Z

, Li S

, Lin G

, Sun G

, Guo J

Superoxide dismutase activity and lipidperoxidation in relation to senescence of rice leaves.

Acta Bot Sin, 1984, 26: 605-615 (in Chinese)

研究了从抽穗开花到籽粒成熟过程中,水稻植株顶部三片叶子的超氧物歧化酶(SOD),脂质过氧化产物丙二醛(MDA)含量及二磷酸核酮糖羧化酶活性的变化。实验结果表明:叶片的衰老伴随着 SOD 活性、RuBP 羧化酶活性及叶绿素含量的降低、丙二醛含量显著增高。分离了三个 SOD 的同工酶,证明为 Cu—Zn SOD。观察了 SOD 同工酶在叶片老化及酶液存放不同时间中的变化。讨论了叶片衰老过程中氧自由基对酶及质膜的损伤影响。

... 参照林植芳等^[27]的方法测定CAT活性, 吸取50 μ ...

... 参照林植芳^[27]的方法测定 ...

2000

0.0

... 叶片失绿速率、持绿时间和绿叶面积等可作为评价衰老进程和程度的指标^[7,28,29] ...

2007

0.0

... 叶片失绿速率、持绿时间和绿叶面积等可作为评价衰老进程和程度的指标^[7,28,29] ...

2010

0.0

胡秀丽, 李艳辉, 杨海荣, 刘全军, 李潮海. HSP70可提高干旱高温复合胁迫诱导的玉米叶片抗氧化防护能力. 作物学报, 2010, 36: 636-644

Hu X

, Li Y

, Yang H

, Liu Q

, Li C

Heat shock protein 70 may improve the ability of antioxidant defense induced by the combination of drought and heat in maize leaves.

Acta Agron Sin, 2010, 36: 636-644 (in Chinese with English abstract)

In order to determine the mechanism of heat shock protein (HSP70) increasing crops endurance to the combination of drought and heat, we investigated the physiological characteristics of four maize varieties with different responses to drought and heat stresses. The results are as follows: (1) Under drought, heat, the combination of drought and heat, the increase of malondialdelehyde (MDA) content in leaf was the lowest in Zhuyu 309 without endurance to three stresses and the highest in Longyu 602 with endurance to three stresses; under drought, leaf MDA increase in Zhengdan958 with drought-endurance was less than that in Xundan 20 leaves with heat-endurance; under heat, leaf MDA increase was more in Zhengdan 958 than in Xundan20. (2) In Zhengdan958, Xundan20, Longyu602 leaves, the increase of ascorbate peroxidese (APX), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT) activities was more than that in Zhuyu 309 leaves under drought, heat, the combination of drought and heat; under drought, APX, GR, SOD, CAT activities of Zhengdan 958 leaves increased significantly more than those of Xundan 20’, but those were contrary under heat; under the combination of drought and heat, APX, GR, SOD activities of Longyu 602 leaves increased significantly more than those of Zhengdan 958 and Xundan 20. (3) The pretreatment with HSP70 inhibitor quercetin (Q) significantly inhibited the increase of antioxidant enzymes activities in leaves of 4 maize varieties exposed to the three stresses. These results suggested that HSP70 involved in the increase of antioxidant enzyme activity in leaves of 4 maize varieties exposed to drought, heat and their combination, and APX, GR, SOD activities could be used as chemical and biological indicators to evaluate the crop endurance to drought, heat, and the combination of drought and heat stresses.

为确定热休克蛋白 70 (HSP70) 提高作物耐干旱高温复合胁迫的机制，对干旱、高温反应不同的 4 个玉米品种的生理特性进行了研究。结果显示： (1) 在干旱、高温、干旱高温复合胁迫条件下，叶片丙二醛 (MDA) 增加量以隆玉 602 最低，驻玉 309 最高；在干旱胁迫条件下，郑单 958 叶片 MDA 含量低于浚单 20 ，而在高温胁迫条件下，浚单 20 叶片 MDA 含量低于郑单 958 。 (2) 在干旱、高温、干旱高温复合胁迫条件下，隆玉 602 、郑单 958 、浚单 20 三个品种叶片抗氧化防护系统如抗坏血酸过氧化物酶 (APX) 、谷胱苷肽还原酶 (GR) 、超氧化物歧化酶 (SOD) 、过氧化氢酶 (CAT) 活性增加量均高于驻玉 309 ；在干旱条件下，郑单 958 叶片 APX 、 GR 、 SOD 、 CAT 活性增加量显著高于浚单 20 ，在高温条件下，两个品种的表现则相反；在干旱高温复合胁迫条件下，隆玉 602 叶片 APX 、 GR 、 SOD 活性增加量显著高于郑单 958 和浚单 20 。 (3) HSP70 抑制剂斛皮素 (Quercetin, Q) 预处理显著抑制了 3 种胁迫诱导的 4 个品种叶片抗氧化酶活性的增加。这些研究结果暗示 HSP70 提高了干旱、高温、干旱高温复合胁迫诱导的抗氧化防护酶活性，且 APX 、 GR 、 SOD 这 3 个抗氧化防护酶活性可以作为评价作物耐干旱、高温和干旱高温复合胁迫的生化指标。

... 水分、温度和养分亏缺等逆境胁迫条件以及增加种植密度, 均导致玉米叶片的保护酶活性提高, 从而有效减轻膜脂过氧化程度^[12,14,30] ...

2012

0.0

宋振伟, 齐华, 张振平, 钱春荣, 郭金瑞, 邓艾兴, 张卫建. 春玉米中单909农艺性状和产量对密植的响应及其在东北不同区域的差异. 作物学报, 2012, 38: 2267-2277

Song Z

, Qi

, Zhang Z

, Qian C

, Guo J

, Deng A

, Zhang W

Effects of plant density on agronomic traits and yield in spring maize Zhongdan 909 and their regional differences in northeast China.

Acta Agron Sin, 2012, 38: 2267-2277 (in Chinese with English abstract)

It is well evidenced that higher plant density will give higher grain yields, and the ecological situations of precipitation, air temperature and soil conditions are the key factors of plant density decision. Given the great regional variations of precipitation and temperature, to learn the integrated responses of crop growth to plant density and regional ecological situation will play an important role in designing optimal density with higher yield in Northeast China. Field experiments were conducted in Shenyang, Gongzhuling, Harbin, Huadian, and Taonan using spring maize cultivar Zhongdan 909 to determine the comprehensive effects of plant densities and regional ecological conditions on crop agronomic characters and grain yield. The results showed that, higher plant density significantly increased the plant height and ear height, and decreased the stem diameter. Regional ecological conditions had significant effect on plant height but less effect on ear height and stem diameter. With the increase of plant density, the population leaf area index (LAI) increased significantly. Meanwhile, the increment of heat and precipitation increased the LAI. The increase of population dry matter accumulation under higher plant density offset the decrease of dry matter accumulation per plant which ensured the higher grain yield. Under the plant density of 9.00 × 10 4 plant ha -1 , the potential productivity for cultivar Zhongdan 909 was fully developed in the experiments. But regional differences of precipitation, air temperature and soil characters influenced the appropriate plant density. The optimum plant density should be from 8.6 to9.6×10 4 plant ha -1 under different ecological conditions in Northeast China.

增密是实现东北春玉米大面积增产的关键技术，水热和土壤等区域生态条件是决定作物密度高低的关键因素。东北的区域生态条件差异显著 , 阐明作物对密度和区域生态条件的综合响应对东北春玉米增密增产具有重要的理论与实践指导意义。本研究以中单 909 为供试品种 , 在代表东北不同生态条件的辽宁沈阳、吉林公主岭、黑龙江哈尔滨、吉林桦甸和吉林洮南等 5 个试验点设置密度试验 , 研究春玉米农艺性状与产量对密度和区域生态条件的综合响应。结果表明 , 密植导致株高与穗位高增加 , 茎粗降低。区域生态条件主要影响玉米株高 , 对茎粗和穗位高的影响不显著。随密度增加 , 群体叶面积指数 (LAI) 显著增加 , 尤其是随热量条件改善 , 群体 LAI 呈显著增加趋势。在一定范围内 , 密植可以通过提高群体干物质生产力弥补单株生产力的下降 , 从而获得高产 ; 本试验条件下 , 中单 909 在 9.00 万株 hm -2 左右密度下的密植增产潜力得到充分发挥 , 而区域间因生态条件不同 , 高产种植密度存在显著差异 , 其适宜密植范围在 8.6~ 9.6 万株 hm -2 之间。

... 产量与种植密度呈二次曲线关系^[31], 当密度超过适宜密度时, 对光温水肥的竞争导致群体恶化, 叶片早衰直接影响着籽粒灌浆的进程, 最终影响产量和品质^[32] ...

1999

0.0

丰明乾, 孙俊荣, 郭蔼光. 小麦灌浆期旗叶蛋白质运转与籽粒蛋白质积累的关系. 陕西农业科学, 1999, (2): 1-3

Feng M

, Sun J

, Guo A

The relation of wheat flag leaf protein operation and grain protein accumulation during the grain-filling period.

Shaanxi J Agric Sci, 1999, (2): 1-3 (in Chinese with English abstract)

探讨了籽粒蛋白含量差异较大的２个小麦品种———小偃６号（蛋白含量为１６％）和小偃１０７（蛋白含量为１２％）灌浆期旗叶蛋白质运转的规律与差异及其对于籽粒蛋白质积累的影响。结果发现：①灌浆前期（开花～花后１０ｄ）旗叶总蛋白含量、可溶性蛋白含量、游离氨基酸含量下降缓慢，花后１４ｄ起迅速下降；籽粒蛋白质积累（以每粒总蛋白量计）呈慢－快－慢的变化趋势，灌浆中后期（花后１７～２７ｄ）积累非常迅速。②开花期小偃６号旗叶总蛋白含量、可溶性蛋白含量、游离氨基酸含量与小偃１０７差别不大，花后１４ｄ起由于水解酶活性的升高开始明显低于后者；籽粒总蛋白量在开花期差别也不大，花后１７ｄ起开始明显高于后者。这说明灌浆中后期是籽粒蛋白质积累的关键时期；小偃６号能更好地启动自身的降解机制，能将旗叶同化的氮素更充分地再运转到籽粒中去，最终使得籽粒蛋白含量高于小偃１０７。

1999

0.0

王空军, 胡昌浩, 董树亭, 刘开昌, 孙庆泉. 我国不同年代玉米品种开花后叶片保护酶活性及膜脂过氧化作用的演进. 作物学报, 1999, 25: 700-706

Wang K

, Hu C

, Dong S

, Liu K

, Sun Q

Changes of the protective enzyme activities and lipid peroxidation after anthesis among maize varieties planted in different years.

Acta Agron Sin, 1999, 25: 700-706

The main maize varieties planted popularly in 1950’s to 1990’s in China were chosento analysis the changes of activity of enzymes protected against active oxygen in leaves after anthesis. The result indicated that activities of superoxide dismutase (SOD)，catalase (CAT)，and peroxidase (POD) inc

通过比较研究我国50年代、70年代和90年代的几个主栽玉米((Zea mays L.)品种开花后叶片中抗氧化保护酶活性的变化得出：随品种更替叶片SOD、CAT和POD活性增加，膜脂过氧化产物MDA含量降低，在生育后期这种趋势愈加明显，不同叶位间以中下部叶片尤为显著。这些特征可能是近代玉米品种高产抗逆的有利因素之一。

... 前人研究表明, 玉米中下部叶片保护酶活性高和膜脂过氧化程度低是近代玉米品种高产抗逆的内在因素^[33], 而ECK处理提高了穗位叶和基部叶片SOD、POD和CAT活性, 提高了可溶性蛋白含量和叶绿素含量, 降低了膜脂过氧化程度, 提高了作物的抗逆性, 延缓了叶片的衰老进程, 最终提高了产量 ...