乙矮合剂对不同密度夏玉米花粒期叶片氮素同化与早衰的影响

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卢霖, 董志强, 董学瑞, 焦浏, 李光彦, 高娇. . 乙矮合剂对不同密度夏玉米花粒期叶片氮素同化与早衰的影响. 作物学报, 2015, 41(12): 1870-1879
LU Lin, DONG Zhi-Qiang, DONG Xue-Rui, JIAO Liu, LI Guang-Yan, GAO Jiao. . Effects of Ethylene-Chlormequat-Potassium on Leaf Nitrogen Assimilation after Anthesis and Early Senescence under Different Planting Densities. ACTA AGRONOMICA SINICA, 2015, 41(12): 1870-1879 复制到剪切板

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作物学报编辑部

乙矮合剂对不同密度夏玉米花粒期叶片氮素同化与早衰的影响

卢霖¹, 董志强^1,^*, 董学瑞¹, 焦浏¹, 李光彦¹, 高娇^1,²

¹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

²北京市农业机械试验鉴定推广站, 北京100079

^*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:2015-03-30 接受日期:2015-07-20 网络出版日期:2015-08-12

基金:本研究由国家自然科学基金项目(31470087)和国家科技支撑计划(粮食丰产科技工程)项目(2011BAD16B14)资助

摘要

为探讨乙矮合剂调控夏玉米氮素同化和防止后期早衰的生理机制, 为建立华北夏玉米区密植高产稳产化学调控技术提供理论依据, 2013—2014年在中国农业科学院新乡试验站, 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, 研究密度梯度对花后玉米穗位叶氮同化特征和早衰的影响, 以及ECK的化学调控效应。结果表明, 灌浆期(花后0~40 d), 穗位叶硝酸还原酶(NR)活性和谷氨酰胺合成酶(GS)活性随密度增加而显著下降; 灌浆后期(花后30~40 d), 谷草转氨酶(GOT)和谷丙转氨酶(GPT)活性随种植密度增加而显著降低。穗位叶叶绿素相对含量、可溶性蛋白含量和游离氨基酸含量在灌浆中后期(花后20~40 d)随种植密度增加而显著降低; 两品种产量在7.5万株 hm^-2密度达最大值, 7.5~10.5万株 hm^-2密度群体产量下降, 高密群体易发生早衰。ECK处理显著提高了各密度群体灌浆中后期(花后20~40 d)穗位叶NR活性、GS活性、游离氨基酸含量、可溶性蛋白含量和叶绿素含量; 显著提高了高密群体(7.5~10.5万株 hm^-2) GOT活性和GPT活性; 较高密群体下(7.5~10.5万株 hm^-2), 中单909和浚单20较各自对照的增产幅度分别为5.59%~6.63%和6.73%~8.10%。ECK处理提高了高密群体夏玉米穗位叶片氮代谢关键酶活性及其产物含量, 保证密植群体氮代谢正常进行, 有效防止早衰及提高产量。综上所述, 采用合理的种植密度并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; 叶片氮同化; 早衰

Effects of Ethylene-Chlormequat-Potassium on Leaf Nitrogen Assimilation after Anthesis and Early Senescence under Different Planting Densities

LU Lin¹, DONG Zhi-Qiang^1,^*, DONG Xue-Rui¹, JIAO Liu¹, LI Guang-Yan¹, GAO Jiao^1,²

¹ Institute of Crop Science, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Beijing 100081, China

² Beijing Agricultural Machinery Testing & Extension Station, Beijing 100079, 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)

Abstract

To explore the effects of ethylene-chlormequat-potassium (ECK) on the physiological mechanisms of nitrogen assimilation and early senescence in summer maize, and provide a theoretical basis for high and stable yields of summer maize under high plant density by chemical regulation technology in North China Plain, we conducted a field experiment using two varieties of Zhongdan 909 and Xundan 20 with different planting densities in 2013 and 2014. The results showed that increasing plant density significantly decreased the activities of nitrate reductase (NR) and glutamine synthetase (GS) after anthesis, glutamate oxaloacetic transaminase (GOT) activity at anthesis, and glutamate pyruvate transaminase (GPT) activity at 30 days after anthesis. The soluble protein and free amino acid contents at 20 days after anthesis, and the SPAD value at 10 days after anthesis were significantly decreased with increasing plant density. For both varieties, grain yield reached the highest under 7.5×10⁴ plants ha^-1, while decreased under the density of ≥ 7.5×10⁴ plants ha^-1. The higher density resulted in early senescence. ECK treatment significantly increased the activities of NR, GS, and contents of free amino acid, soluble protein and SPAD value during middle and late grain filling stages. ECK treatment also significantly improved the GOT and GPT activities under 7.5×10⁴-10.5×10⁴ plants ha^-1. Under the density ≥ 7.5×10⁴ plant ha^-1, the yields of Zhongdan 909 and Xundan 20 compared with their own control were respectively increased by 5.59%-6.63% and 6.73%-8.10%. ECK treatment significantly increased the nitrogen assimilation key enzyme activity of ear leaf and its product content under different planting densities, promoted normal nitrogen assimilation and prevented early senescence under higher planting densities, therefore increased yield. Thus, an appropriate planting density combined with ECK application could be an important technique for achieving high grain yield for summer maize production in North China Plain.

Keyword: Summer maize; Ethylene-Chlormequat-Potassium; Planting density; Leaf nitrogen assimilation; Early senescence

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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, 增加密度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导致个体生长发育差, 根系活力低, 地上部叶片功能期缩短, 最终导致群体早衰, 限制了产量的提高^{[3, 4]}。玉米群体早衰与生育后期氮素代谢状况密切相关。已有研究表明, 增加种植密度会影响植株对氮素的吸收、同化、转运和分配, 群体发育不良, 最终影响产量^[5]。从氮素同化过程分析, 增加密度可以导致夏玉米生育后期叶片硝酸还原酶(NR)、谷氨酰胺合成酶(GS)活性显著降低^[6], 其中, 花粒期叶NR活性可调控可溶性蛋白的合成^[7], 而可溶性蛋白含量与植株体内生理代谢的强度密切相关^[8], 进一步影响叶片的功能与衰老, 影响光合产物在籽粒中的积累和最终产量。在叶片衰老过程中, 有关玉米氮代谢关键酶活性变化的研究尚未见报道, 但是, 花生叶片衰老过程中, 氮素代谢关键酶NR活性最先下降^[9]; 以烟草为材料的研究结果表明, 氮低效型烤烟衰老时间早, 且NR、GS活性降低, 与氮高效型烟草相比差异显著^[10]。

为了缓解增加密度给玉米氮素同化带来的负效应, 将适宜的种植密度和种植方式相结合^[6], 采用分次施氮肥, 且适当增加花粒肥比例^[11]等栽培措施, 在一定程度上, 提高了玉米密植群体叶片中氮代谢相关酶活性, 促进了氮素的吸收利用, 延缓了植株衰老, 在一定密度范围内, 提高了籽粒产量。应用化学调控技术也可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, 最终影响作物的产量形成^{[12, 13, 14]}。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^{[15, 16]}。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^{[17, 18, 19]}。在干旱逆境条件下, 叶面喷施乙烯利可以提高叶片NR和GS活性, 提高玉米总叶绿素含量^[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、抗倒伏和抗逆境胁迫方面效果显著^{[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氮素同化过程及抗早衰效果的研究, 尤其是调控氮素代谢关键酶活性变化以及氮素同化效果方面的研究, 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氮同化关键酶活性及其同化产物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氮素同化和防止后期早衰的生理机制, 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 (以下简称ZD, 由中国农业科学院作物科学研究所选育, 耐密性较强)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, 大部分集中在6月至9月份, 约占全年降雨量的75%。试验地土壤为黏壤两合土, 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5个密度水平, 即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, 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。基肥施复合肥(N∶ P₂O₅∶ K₂O=15∶ 15∶ 15, 总养分≥ 45%) 375 kg hm^-2, 追肥施尿素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(穗位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。硝酸还原酶样品于9:00取样, 现取现测。

1.2.1 氮代谢关键酶活性

参考李合生^[23]的磺胺比色法测定硝酸还原酶(NR)活性; 参照王学奎^[24]的方法测定谷氨酰胺合成酶(GS)活性, 以540 nm处吸光度的上升值间接表示酶活性。参考吴良欢等^[25]的方法测定谷草转氨酶(GOT)、谷丙转氨酶(GPT)活性, 以每克植物鲜样在30 min内反应生成的丙酮酸量(µ g)表示。

1.2.2 可溶性蛋白含量

采用考马斯亮蓝G-250染色法测定^[26]。

1.2.3 游离氨基酸含量

采用茚三酮比色法测定^[27]。

1.2.4 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叶绿素相对含量(SPAD值)。

1.2.5 产量

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 试验数据处理

采用Microsoft Excel 2007整理数据和作图, SPSS 17.0进行统计分析, 以LSD检验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穗位叶NR活性的影响

NR催化硝酸盐还原成亚硝酸盐, 调控氮素同化的第一步。花粒期穗位叶NR活性的变化如图1所示, 两品种NR活性均随密度增加而降低, 且花后0~40 d随叶龄增大呈降低趋势; 两品种各处理NR活性与种植密度均呈显著或极显著负相关(r₀= -0.782^{* *}; r₁₀= -0.796^{* *}; r₂₀= -0.649^*; r₃₀= -0.809^{* *}; r₄₀= -0.911^{* *})。

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	图1 乙矮合剂对不同密度夏玉米穗位叶NR活性的影响Fig. 1 Effect of ECK on NR activity of ear leaves of two maize lines under different plant densities

ECK处理, 花后0~40 d, 高密度群体(D₃、D₄、D₅) ZD和XD的NR活性显著高于CK。与CK相比, ZD-TR在D₃、D₄、D₅密度条件下的NR活性分别增加2.06%~57.21%、2.42%~67.86%、14.54%~70.97%。XD-TR在D₃、D₄、D₅密度条件下的NR活性分别增加7.89%~34.60%、4.11%~38.83%、21.74%~83.88%。低密度下(D₁、D₂) XD-TR高于CK但未达显著水平, 增幅为2.37%~10.10%。

2.2 乙矮合剂对不同密度夏玉米花粒期穗位叶GS活性的影响

GS主要催化谷氨酸转化为谷氨酰胺。花粒期穗位叶GS活性的变化如图2所示, 两品种GS活性随密度增加而降低, 且花后0~40 d内随叶龄增加呈单峰曲线变化, 最大值出现在花后10 d, 之后大幅度下降; 品种间表现为ZD高于XD。相关分析表明, 两品种各处理GS活性与种植密度均呈显著或极显著负相关 (r₀= -0.838^{* *}; r₁₀= -0.661^{* *}; r₂₀= -0.714^*; r₃₀= -0.906^{* *}; r₄₀=-0.836^{* *})。

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	图2 乙矮合剂对不同密度夏玉米穗位叶GS活性的影响 Fig. 2 Effect of ECK on GS activity of ear leaves of two maize lines under different plant densities

ECK处理, 花后0~40 d, 各密度梯度ZD和XD穗位叶GS活性均显著高于CK。与CK相比, D₁~D₅密度下, ZD-TR GS活性分别增加5.65%~31.33%、2.92%~33.68%、7.91%~56.18%、7.95%~64.54%、20.60%~ 61.49%; XD-TR的GS活性分别增加6.27%~26.70%、4.43%~22.40%、1.63%~42.02%、8.83%~133.56%、3.89%~ 35.7%。

2.3 乙矮合剂对不同密度夏玉米花粒期穗位叶GOT和GPT活性的影响

GOT和GPT活性的变化如图3所示, 随着种植密度的增加而下降, 且花后0~40 d内随叶龄增加均呈下降趋势; 但高密度群体(D₄、D₅) GPT活性呈单峰曲线, 峰值分别出现在10 d和20 d; 品种间表现为ZD的GOT和GPT活性高于XD的。相关分析表明, GOT活性和GPT活性均在花后0 d、30 d、40 d与种植密度呈显著或极显著负相关(r_GOT-0= -0.753^{* *}; r_GOT-30= -0.808^{* *}; r_GOT-40= -0.754^*; r_GPT-0= -0.819^{* *}; r_GPT-30= -0.701^*; r_GPT-40= -0.814^*)。

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	图3 乙矮合剂对不同密度夏玉米穗位叶GOT活性和GPT活性的影响Fig. 3 Effect of ECK on GOT activity and GPT activity of ear leaves of two maize lines under different plant densities

ECK处理, 花后0~40 d, 各密度条件下, ZD和XD的GOT和GPT活性高于CK。在D₁~D₅密度下, ZD-TR的GOT活性比CK高0.81%~38.3%; XD-TR比CK高0.63%~29.98%, 低密度群体(D₁、D₂)两品种TR增加不显著。在D₁~D₅密度下, ZD-TR的GPT活性较CK均显著增加, 增幅为0.81%~38.80%; XD-TR的GPT活性较CK增加2.74%~43.23%, D₁密度下增加不显著。

2.4 乙矮合剂对不同密度夏玉米花粒期穗位叶可溶性蛋白含量的影响

可溶性蛋白是氮素同化的最终产物, 是叶片功能和早衰状况的直观指示指标。花粒期ZD和XD穗位叶可溶性蛋白含量的变化如图4所示, 随密度增加而降低, 且花后0~40 d内随叶龄增加呈下降趋势, 其中, 花后20 d起, 低密度群体(D₁、D₂)可溶性蛋白含量平缓下降, 高密度(D₃、D₄、D₅)则下降迅速。品种间表现为ZD高于XD。相关分析表明, 在花后20~ 40 d, 两品种穗位叶可溶性蛋白含量与种植密度均呈显著负相关(r₂₀=-0.774^*; r₃₀=-0.692^*; r₄₀= -0.792^*)。

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	图4 乙矮合剂对不同密度夏玉米穗位叶可溶性蛋白含量的影响Fig. 4 Effect of ECK on soluble protein content of ear leaves of two maize lines under different plant densities

花后20~40 d, 与CK相比, ECK处理显著提高了ZD和XD各密度群体穗位叶可溶性蛋白含量。D₁~D₅ ZD-TR的可溶性蛋白含量较CK分别高3.21%~ 17.56%、9.23%~37.90%、8.84%~24.84%、2.21%~66.32%、20.68%~65.06%。D₁~D₅ XD-TR可溶性蛋白含量较CK分别高2.72%~29.56%、11.37%~50.78%、14.84%~ 29.89%、28.07%~53.09%、14.19%~115.68%。

2.5 乙矮合剂对不同密度夏玉米花粒期穗位叶游离氨基酸含量的影响

如图5所示, ZD和XD花粒期穗位叶游离氨基酸含量随密度增加而降低; 花后0~40 d内随叶龄增加呈单峰曲线变化趋势, 两玉米品种D₁、D₂密度在花后20 d达峰值, D₄、D₅密度下在花后10 d达峰值; 而D₃密度下, 两品种峰值期不同, ZD峰值出现在花后20 d, XD则出现在花后10 d。ZD的可溶性蛋白含量显著高于XD。相关分析结果表明, 在花后20~ 40 d游离氨基酸含量与种植密度呈显著或极显著负相关(r₂₀= -0.887^{* *}; r₃₀= -0.711^*; r₄₀= -0.841^*)。

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	图5 乙矮合剂对不同密度夏玉米穗位叶游离氨基酸含量的影响 Fig. 5 Effect of ECK on free amino acid content of ear leaves of two maize lines under different plant densities

ECK处理后, 花后0~40 d, 各密度条件下, ZD和XD穗位叶游离氨基酸含量TR均显著高于CK。其中, ZD-TR的游离氨基酸含量较CK增加3.59%~ 26.39%。XD-TR的游离氨基酸含量较CK增加2.67%~ 37.50%。

2.6 乙矮合剂对不同密度夏玉米花粒期穗位叶SPAD值的影响

SPAD值的变化如图6所示, 在D₁、D₂、D₃密度下, 花后20 d起开始下降, 在D₄、D₅密度下则在花后10 d开始迅速下降; 品种间差异不显著。相关分析表明, SPAD值在花后10~40 d与种植密度呈显著或极显著负相关(r₁₀= -0.759^*; r₂₀= -0.936^{* *}; r₃₀= -0.843^{* *}; r₄₀= -0.843^{* *})。

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	图6 乙矮合剂对不同密度夏玉米穗位叶叶绿素相对含量的影响 Fig. 6 Effect of ECK on SPAD value of ear leaves of two maize lines under different plant densities

ECK处理后, 显著提高D₁、D₂密度下花后30~40 d的SPAD值, ZD-TR和XD-TR的SPAD值较CK分别高5.14%~3.90%、3.27%~7.07%。显著提高D₃、D₄、D₅密度下花后20~40 d SPAD值, ZD-TR和XD-TR的SPAD值较CK分别高5.62%~13.89%和6.60%~27.19%。

2.7 乙矮合剂对不同密度夏玉米产量的影响

由图7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, 差异均达到显著水平(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密度下分别增产7.51%、8.10%和6.73%。

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	图7 乙矮合剂对不同密度夏玉米产量的影响 Fig. 7 Effect of ECK on yield of two maize lines under different plant densities

3 讨论

叶片是氮素同化的主要场所, 在叶片中, 硝态氮还原成氨态氮, 进一步通过转氨基作用形成氨基酸和酰胺, 之后以氨基酸、酰胺的形式运往籽粒或幼嫩器官, 参与多肽和蛋白质的合成。研究发现, 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, 诱导叶片早衰。目前, 有关密度与氮素代谢方面的研究较少。研究发现, 增加种植密度显著影响冬小麦、黑小麦和大豆氮素吸收、同化和分配^{[28, 29, 30]}。李洪岐等^[6]研究发现, 玉米叶片NR活性随种植密度增加呈下降趋势, 本研究结果表明, 花粒期穗位叶NR活性在花后0~40 d与种植密度呈显著或极显著负相关, 进一步证明叶片NR活性受密度影响显著。NR催化硝酸盐还原成亚硝酸盐, 调控氮素同化的第一步, 是植物氮代谢的限速酶, 其活性高低是氮代谢水平的直接反映^[31]。由此, 我们推测, 增加种植密度导致的后期叶片早衰, 与NR活性下降密切相关。

在氮素同化过程中, 转氨基作用决定着多种氨基酸的合成, 其中, GS催化无机氮(氨态和硝态氮)转化为有机氮(氨基酸和酰胺); GS/GOGAT循环催化谷氨酰胺和α -酮戊二酸之间的氨基转移, 调节谷氨酸的生成; 该过程所生成的谷氨酸则在GOT和GPT等催化下转化为天门冬氨酸、丙氨酸等其他氨基酸, 为籽粒蛋白合成代谢提供各种氨基酸供体^{[32, 33, 34]}。前人研究发现, 玉米叶片GS活性随种植密度增加呈下降趋势^[6], 本研究结果表明, 花粒期穗位叶GS、GOT和GPT活性均随密度增加而显著降低, 并且, 在灌浆中后期(花后30~40 d)随密度的增加而下降的幅度最为显著。由此可见, 增加密度导致灌浆中后期叶片GS、GOT和GPT等转氨酶活性下降, 直接诱导叶片早衰。游离氨基酸含量、可溶性蛋白含量和叶绿素含量是指示叶片早衰的直接指标, 且各项指标之间密切相关^[35]。研究表明, 增加种植密度导致叶片可溶性蛋白含量和叶绿素含量下降^[36], 本研究结果发现, 游离氨基酸、可溶性蛋白和叶绿素含量与密度在灌浆前期(花后0~10 d)相关性较小; 在灌浆中后期(花后20~40 d), 呈极显著负相关, 即随种植密度增加显著降低, 从而加速了叶片的衰老进程。这可能与灌浆中后期高密群体叶片NR^[37]、GS、GOT和GPT活性降低, 营养器官中的含氮物质降解, 以游离氨基酸的形式向籽粒中迅速转移有关。本研究发现, NR、GS、GOT及GPT活性、游离氨基酸含量、可溶性蛋白含量和叶绿素含量均随密度的增加而下降。但是, 在各密度群体, 所有取样时期NR和GS活性下降均与种植密度呈显著或极显著负相关, 而其他指标则呈阶段性显著或极显著负相关。因此, NR和GS活性可作为评价高密群体玉米叶片早衰的氮素代谢关键生理指标。

ECK处理后, 玉米叶片NR活性、GS活性、游离氨基酸含量提高; 高密群体GOT活性(D₃~D₅密度)、GPT活性(D₂~D₅密度)显著提高; 灌浆后期(花后20~40 d)叶片可溶性蛋白含量和SPAD值显著增加。进一步分析发现, ECK处理能够提高密植群体下玉米抗氧化系统酶活, 降低活性氧产生速率, 提高叶绿素含量, 提高玉米抗逆性^{[21, 22, 23]}。乙烯利具有提高玉米叶片NR活性作用^[20], 而ECK主成分是乙烯利, 因而ECK处理后提高了NR活性和GS活性, 促进氮素同化作用, 进而提高了叶片中叶绿素、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。

产量与种植密度呈二次曲线关系^[38], 当超过适宜密度时, 光温水肥竞争导致群体恶化, 叶片早衰直接影响着籽粒灌浆过程, 最终影响产量和品质^[37]。本研究发现, 增加种植密度导致叶片NR、GS、GOT和GPT活性降低, 导致叶片叶绿素和可溶性蛋白含量降低^[36], 诱导叶片早衰, 最终导致产量下降^{[13, 40]}。因此, 提高氮素代谢相关酶活性, 可以提高叶绿素与可溶性蛋白含量, 调节碳氮代谢平衡, 延缓植株衰老, 最终提高籽粒产量。本研究发现, ECK处理可提高叶片NR和GS活性, 提高高密群体叶片GOT和GPT活性, 促进氮素吸收和同化, 提高玉米叶片叶绿素、可溶性蛋白和游离氨基酸含量, 增强玉米后期氮素代谢能力, 促进碳化物、氮化物等营养体物质向籽粒的转移, 最终提高产量。

4 结论

中单909和浚单20不同密度群体, 灌浆期(花后0~40 d)穗位叶NR活性和GS活性随密度增加而显著下降; 灌浆后期(花后30~40 d) GOT和GPT活性随种植密度增加而显著降低。穗位叶叶绿素相对含量、可溶性蛋白含量和游离氨基酸含量在灌浆中后期(花后20~40 d)随种植密度增加而显著降低。NR和GS活性可作为评价高密群体玉米叶片早衰的氮素代谢关键生理指标。ECK处理可显著提高各密度群体灌浆中后期(花后20~40 d)穗位叶NR活性、GS活性、游离氨基酸含量、可溶性蛋白含量和叶绿素含量; 显著提高高密群体(7.5~10.5万株 hm^-2)GOT和GPT活性; 改善产量构成因素, 提高产量; 中单909和浚单20高密群体(7.5~10.5万株 hm^-2)分别增产5.59%~6.63%和6.73%~8.10%。ECK处理提高了高密群体夏玉米穗位叶片氮代谢关键酶活性及其产物含量, 保证密植群体氮代谢正常进行, 有效防止早衰, 提高了产量。

The authors have declared that no competing interests exist.

作者已声明无竞争性利益关系。The authors have declared that no competing interests exist.

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[26]	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: South China University of Technology Press, 2002. pp 35-128(in Chinese) [本文引用:1]
[27]	何照范. 粮油籽粒品质及其分析技术. 北京: 农业出版社, 1985. pp 57-59 He Z F. Grain Quality and Its Analysis Technology. Beijing: Agriculture Press, 1985. pp 57-59(in Chinese) [本文引用:1]
[28]	沈学善, 李金才, 屈会娟, 魏凤珍, 王成雨. 种植密度对晚播冬小麦氮素同化积累分配及利用效率的影响. 中国农业大学学报, 2009, 14: 41-46 Shen X S, Li J C, Qu H J, Wei F Z, Wang C Y. Effects of planting density on assimilation, accumulation, distribution and use efficiency of nitrogen in late sowing winter wheat. J Chin Agric Univ, 2009, 14: 41-46 (in Chinese with English abstract) [本文引用:1]
[29]	张晓艳, 郑殿峰, 冯乃杰, 李建英, 杜吉到. 密度对大豆群体碳氮代谢相关指标及产量、品质的影响. 干旱地区农业研究, 2011, 29: 128-132 Zhang X Y, Zheng D F, Feng N J, Li J Y, Du J D. Effect of plant density on soybean carbon and nitrogen metabolism, yield and quality. Agric Res Arid Areas, 2011, 29: 128-132 (in Chinese with English abstract) [本文引用:1]
[30]	李晶, 吉彪, 商文楠, 陈龙涛, 魏玲, 魏湜. 密度和氮素水平对小黑麦氮代谢相关酶活性和子粒营养品质的影响. 植物营养与肥料学报, 2010, 16: 1063-1068 Li J, Ji B, Shang W N, Chen L T, Wei L, Wei S. Effects of density and nitrogen on relevant enzyme activity of nitrogen metabolism and nutritional quality of grain in triticale. Plant Nutr Fert Sci, 2010, 16: 1063-1068 (in Chinese with English abstract) [本文引用:1]
[31]	Xu G H, Fan X R, Anthony J. Plant nitrogen assimilation and use efficiency. Annu Rev Plant Biol, 2012, 63: 153-82 [本文引用:1]
[32]	Miflin B, Habash D. The role of glutamine synthetase and gluta-mate dehydrogenase in nitrogen assimilation and possibilities for improvement in the nitrogen utilization of crops. J Exp Bot, 2002, 53: 979-987 [本文引用:1]
[33]	Daubresse C M, Carrayol E, Valadier M H. The two nitrogen mobilisation and senescence-associated GS1 and GDH genes are controlled by C and N metabolites. Planta, 2005, 221: 580-588 [本文引用:1]
[34]	Stéphanie M, Bernard, Dimah Z. The importance of cytosolic glutamine synthetase in nitrogen assimilation and recycling. New Phytol, 2009, 182: 608-620 [本文引用:1]
[35]	肖启银, 任万军, 杨文钰, 卢庭启, 刘代银. 免耕留茬抛秧栽培模式对水稻生育后期叶片衰老特性的影响. 作物学报, 2009, 35: 1562-1567 Xiao Q Y, Ren W J, Yang W Y, Lu T Q, Liu D Y. Effect of cultivation method of broadcasting rice seedlings in the field with stand ing-stubbles under no-tillage condition on senescence characteristics of leaves during late stages of rice development. Acta Agron Sin, 2009, 35: 1562-1567 (in Chinese with English abstract) [本文引用:1]
[36]	马超, 黄晓书, 李鹏坤, 卫丽. 种植密度对夏玉米果穗叶生理功能衰退的影响. 玉米科学, 2010, 18(2): 50-53 Ma C, Huang X S, Li P K, Wei L. Effects of planting density on physiological decline on ear leaf of summer maize. J Maize Sci, 2010, 18(2): 50-53 (in Chinese with English abstract) [本文引用:2]
[37]	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:2]
[38]	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]
[39]	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:1]
[40]	杨亮, 赵宏伟, 刘锦红. 氮素用量对春玉米功能叶片谷氨酰胺合成酶活性及产量的影响. 东北农业大学学报, 2007, 38: 320-324 Yang L, Zhao H W, Liu J H. Effects of different nitrogen application on GS activity and yield in different quality spring maize varieties. J Northeast Agric Univ, 2007, 38: 320-324 (in Chinese with English abstract) [本文引用:1]

2005

0.0

... 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 rras 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导致个体生长发育差, 根系活力低, 地上部叶片功能期缩短, 最终导致群体早衰, 限制了产量的提高^[3,4] ...

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。

2008

0.0

吕丽华, 陶洪斌, 王璞, 刘明, 赵明, 王润正. 种植密度对夏玉米碳氮代谢和氮利用率的影响. 作物学报, 2008, 34: 718-723

Lü L

, Tao H

, Wang

, Liu

, Zhao

, Wang R

. Carbon and nitrogen metabolism and nitrogen use efficiency in summer maize under different planting densities. Acta Agron Sin, 2008, 34: 718-723 (in Chinese with English abstract)

We conducted a field experiment to obtain high yield and high recovery of N fertilizer simultaneously through regulating carbon and nitrogen metabolism under suitable planting density in 2006. The main results showed that plants grew well under low or medium densities [9.75×104 (D 1-1 ) and 11.25×104 (D 1-2 ) plants ha-1 for CF008; 8.25×10 4 (D 2-1 ) and 9.75×10 4 (D 2-2 ) plants ha -1 for Zhengdan 958; and 6.75×10 4 (D 3-1 ) and 8.25×10 4 (D 3-2 ) plants ha -1 for Jinhai 5]. Although C and N accumulation in stem/sheath and leaf at silking stage and C and N translocation rate were higher under medium or high density than under low density, grain yield, N uptake efficiency, N use efficiency, and recovery of N fertilizer were significantly higher under low or medium densities. N accumulation in shoots before silking was higher under medium or high density than under low density, N in shoot accumulation at maturity and N in grain were higher under low or medium density. Hence N accumulation in shoot after silking stage was important for grain N accumulation. We also obtained some quantitative criteria based on the research in Wuqiao area: for the three varieties of maize, grain yield was 10 262–11 461 kg ha -1 , recovery of N fertilizer was 23.00%–34.11% under low or medium densities.

研究了低、中、高3个种植密度对夏播玉米CF008、郑单958和金海5号碳氮积累、运转及氮肥利用的影响, 以期通过密度调控碳氮代谢, 实现产量与氮肥效率协同提高。结果表明, 吐丝期茎叶总糖和全氮积累量和茎叶总糖和全氮的运转率均以中或高密度下较高, 而籽粒产量、氮素吸收效率、氮素利用效率和氮肥利用率均以中或低密度显著高于高密度。吐丝前地上部氮素积累量以中高密度下较高, 但成熟期地上部总氮量及籽粒氮量均以中低密度较高, 表明吐丝期后植株氮素积累量对玉米籽粒氮贡献较大。在中低密度下, 3个品种夏玉米产量达10 262~11 461 kg hm -2 , 氮肥利用率达23.00%~34.11%。

... 已有研究表明, 增加种植密度会影响植株对氮素的吸收、同化、转运和分配, 群体发育不良, 最终影响产量^[5] ...

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。

... 从氮素同化过程分析, 增加密度可以导致夏玉米生育后期叶片硝酸还原酶(NR)、谷氨酰胺合成酶(GS)活性显著降低^[6], 其中, 花粒期叶NR活性可调控可溶性蛋白的合成^[7], 而可溶性蛋白含量与植株体内生理代谢的强度密切相关^[8], 进一步影响叶片的功能与衰老, 影响光合产物在籽粒中的积累和最终产量 ...

... 为了缓解增加密度给玉米氮素同化带来的负效应, 将适宜的种植密度和种植方式相结合^[6], 采用分次施氮肥, 且适当增加花粒肥比例^[11]等栽培措施, 在一定程度上, 提高了玉米密植群体叶片中氮代谢相关酶活性, 促进了氮素的吸收利用, 延缓了植株衰老, 在一定密度范围内, 提高了籽粒产量 ...

... 李洪岐等^[6]研究发现, 玉米叶片NR活性随种植密度增加呈下降趋势, 本研究结果表明, 花粒期穗位叶NR活性在花后0~40 d与种植密度呈显著或极显著负相关, 进一步证明叶片NR活性受密度影响显著 ...

... 前人研究发现, 玉米叶片GS活性随种植密度增加呈下降趋势^[6], 本研究结果表明, 花粒期穗位叶GS、GOT和GPT活性均随密度增加而显著降低, 并且, 在灌浆中后期(花后30~40 d)随密度的增加而下降的幅度最为显著 ...

2005

0.0

王小燕, 于振文. 不同小麦品种主要品质性状及相关酶活性研究. 中国农业科学, 2005, 38: 1980-1988

Wang X

, Yu Z

. Differences in characteristics of quality and related enzymes activity of different wheat cultivars. Sci Agric Sin, 2005, 38: 1980-1988 (in Chinese with English abstract)

Nine wheat cultivars with different protein contents, GMP content, wet gluten content, SDS sedimentation, and dough stability time at maturity were classified into three groups: high GMP content and high dough stability time, low GMP content and low dough stability time, and medium GMP content and medium dough stability time. The dynamic changes in the content of soluble protein and the activity of the enzymes in relation to protein synthesis and degradation and their relationships to characteristics of processing quality were studied during grain filling. The results showed that protein content was not related to wet GMP content, SDS sedimentation, and dough stability time but GMP content was significantly related to the said indices, implying that GMP content was more representative to processing quality than protein content. During the early period of grain filling NR and GS activities had significants effect on soluble protein content and during the later period EP, CP and AP activities has significant effects. The group with high GMP content had higher soluble protein content than other groups. The above results indicated that during grain filling, higher soluble protein level, namely high NR and GS activities during the prophase and metaphase, and high EP, CP, and AP activities during the metaphase and anaphase, was the physiological basis for high GMP content.

根据小麦成熟期籽粒的蛋白质、谷蛋白大聚合体(GMP)、湿面筋含量及沉降值、面团稳定时间等蛋白质品质指标的差异，用聚类分析的方法将供试的9个小麦品种分为3组：高GMP含量、高面团稳定时间组；低GMP含量、低面团稳定时间组；中GMP含量、中面团稳定时间组。研究在籽粒灌浆过程中，可溶性蛋白含量、蛋白质合成与分解过程相关酶活性的变化动态，及与蛋白质品质指标的关系。结果表明，蛋白质含量与GMP含量、沉降值、面团稳定时间之间无显著相关性，GMP含量与诸品质指标呈显著正相关，表明GMP含量更能代表加工品质的优劣；灌浆前中期硝酸还原酶（NR）、谷氨酰胺合成酶（GS）活性对可溶性蛋白（SB）含量有显著影响，灌浆中后期内肽酶（EP）、羧肽酶（CP）、氨肽酶（AP）活性对可溶性蛋白含量有显著影响；高GMP组旗叶可溶性蛋白含量显著高于中GMP组和低GMP组。以上结果表明，在灌浆过程中，较高的可溶性蛋白质代谢水平，即灌浆前中期具有较高的NR、GS活性和灌浆中后期具有较高的EP、CP、AP活性，是具有较高的GMP含量的生理基础。

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. 山西师范大学学报, 1997, 11(1): 46-49

Yin L

, Chai X

, Li

, Zhang C

, Hong J

, Liu X

, Zhao W

. Changes of glutamine synthesis and proteolyase indifferent wheat speicies during the leaves nature senescence. J Shanxi Norm Univ, 1997, 11(1): 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.

2001

0.0

李向东, 万勇善, 于振文, 陈雨海, 张高英. 花生叶片衰老过程中氮素代谢指标变化. 植物生态学报, 2001, 25: 549-552

Li X

, Wan Y

, Yu Z

, Chen Y

, Zhang G

. Changes in nitrogen metabolism indices of arachis hypogeal leaf senescence. Acta Phytoecol Sin, 2001, 25: 549-552 (in Chinese with English abstract)

摘　要：以鲁花11和辐8707两个花生（Arachis hypogea L.)品种为材料，对大田条件下花生叶片衰老过程中N素代谢指标变化进行了研究，结果表明，花生叶叶片展开至衰老过程中，蛋白酶活性逐渐升高，叶中N含量逐渐降低；硝酸还原酶（NR）活性、叶绿素、游离氨基酸和可溶性蛋白质含量呈抛物线型变化，最先开始降低的是NR活性，其次是叶绿素含量，最后是游离氨基酸和可溶性蛋白质含量。

... 在叶片衰老过程中, 有关玉米氮代谢关键酶活性变化的研究尚未见报道, 但是, 花生叶片衰老过程中, 氮素代谢关键酶NR活性最先下降^[9] ...

2013

0.0

武云杰, 张小全, 段旺军, 杨铁钊. 不同氮素利用效率基因型烤烟叶片衰老期间氮素代谢差异研究. 中国烟草学报, 2013, 18(5): 23-28

Wu Y

, Zhang X

, Duan W

, Yang T

. N metabolism difference between flue-cured tobacco genotypes with different N efficiency during leaf senescence. Acta Tab Sin, 2013, 18(5): 23-28 (in Chinese with English abstract)

选用氮素利用效率差异较大的两个烤烟基因型中烟100和 K326,采用喷施谷氨酰胺合成酶(GS)抑制剂(Glufosinate)和质外体提取等方法分别测定叶片衰老过程中叶片的氮素代谢产物和相关酶活性的变化,并计算气孔氨气补偿点,研究了烤烟叶片衰老期间氮素的转移和再利用特性与氮素利用效率的关系.结果表明,氮低效基因型烤烟中烟100衰老时间早、速度快,GS和NR活性低,GDH活性高,氨气挥发量大,对叶片NH4+的积累反应速度快,再转移量大,与氮高效基因型烤烟K326相比差异显著.说明烤烟叶片衰老期氮素的再转移和再利用,与叶片衰老程度和速度密切相关.

... 以烟草为材料的研究结果表明, 氮低效型烤烟衰老时间早, 且NR、GS活性降低, 与氮高效型烟草相比差异显著^[10] ...

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.

2009

0.0

... 应用化学调控技术也可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, 最终影响作物的产量形成^[12,13,14] ...

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。

... 本研究发现, 增加种植密度导致叶片NR、GS、GOT和GPT活性降低, 导致叶片叶绿素和可溶性蛋白含量降低^[36], 诱导叶片早衰, 最终导致产量下降^[13,40] ...

2013

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张佳蕾, 王媛媛, 孙莲强, 魏彤彤, 顾学花, 高芳, 李向东. 多效唑对不同品质类型花生产量、品质及相关酶活性的影响. 应用生态学报, 2013, 24: 2850-2856

Zhang J

, Wang Y

, Sun L

, Wei T

, Gu X

, Gao

, Li X

. Effects of paclobutrazol on the yield, quality, and related enzyme activities of different quality type peanut cultivars. Chin J Appl Ecol, 2013, 24: 2850-2856 (in Chinese with English abstract)

Selecting high-protein peanut cultivar KB008, high-fat cultivar Hua17, and high O/L cultivar Nongda818 as test materials, a field experiment was conducted in 2011 and 2012 to study the effects of foliar spraying paclobutrazol (PBZ) at late flowering stage on the kernel yield and quality and the activities of leaf carbon and nitrogen metabolism enzymes of the cultivars. Spraying PBZ increased the pod yield of the cultivars significantly via increasing the pod number per plant, decreasing the pod number per kilogram, and increasing the percentage of double kernel. Spraying PBZ also increased the kernel fat and soluble sugar contents but decreased the kernel protein content to varying degrees, and increased the O/L ratio of high-fat cultivar Hua17 significantly. PBZ increased the kernel fat content while decreased the kernel protein content of Nongda818 significantly, but had little effects on the kernel protein or fat content of the other two cultivars. Spraying PBZ decreased the leaf nitrate reductase activity of the three cultivars at their pod setting stage, and the leaf glutamine synthetase and glutamate dehydrogenase activities at pod setting and filling stages, with the largest decrement for Nongda818 and the smaller one for KB008 and H17. Spraying PBZ decreased the leaf glutamate oxaloacetic transaminase and glutamate pyruvate transaminase activities of the three cultivars at their pod setting and filling stages, illustrating that the decrease of the nitrogen metabolism enzyme activities after spraying PBZ was the main reason of the decreased kernel protein content of the cultivars. PBZ increased the leaf sucrose synthase and sucrose phosphate synthase activities at pod setting and filling stages, being significant for Nongda818. PBZ improved the leaf phosphoenolpyruvate carboxylase and ribulose bisphosphate carboxylase activities of the three cultivars at their pod setting and filling stages, being most significant for Nongda818. It was suggested that the increase of the carbon metabolism enzyme activities was the physiological basis of the improvement of kernel fat content after spraying PBZ.

选用高蛋白品种KB008（KB008）、高脂肪品种花17(H17)和高油酸/亚油酸（O/L）品种农大818（818），在大田栽培条件下，研究了盛花后期叶面喷施多效唑(PBZ)对不同品质类型花生产量、品质及相关碳、氮代谢酶活性的影响.结果表明：喷施PBZ显著增加了3种品质类型花生荚果产量，原因是增加了单株结果数，降低了千克果数而提高了双仁果率.喷施PBZ不同程度地提高了3种类型花生籽仁脂肪和可溶性糖含量，降低了蛋白质含量，显著增加了高脂肪品种H17的O/L值.PBZ使高O/L值品种818的脂肪含量增加显著，同时其蛋白质含量显著降低，而对其他两品种的蛋白质和脂肪含量影响较小.喷施PBZ均降低了3种类型花生结荚期叶片硝酸还原酶（NR）活性及结荚期和饱果期叶片谷氨酰胺合成酶和谷氨酸脱氢酶活性，818的3种酶活性降低幅度最大，KB008和H17的酶活性降幅较小；喷施PBZ均降低了3种类型花生结荚期和饱果期叶片谷草转氨酶和谷丙转氨酶活性.说明氮代谢酶活性的降低是喷施PBZ降低3种类型花生籽仁蛋白质含量的主要原因.喷施PBZ均提高了3品种结荚期和饱果期叶片蔗糖合成酶和磷酸蔗糖合成酶活性，其中显著提高了818的2种酶活性，而对KB008和H17的活性提高不显著；喷施PBZ提高了3品种结荚期和饱果期的磷酸烯醇式丙酮酸羧化酶和1,5-二磷酸核酮糖羧化酶活性，其中对818在结荚期的活性提高最显著，对H17活性提高较小.碳代谢酶活性的增强是喷施PBZ提高花生籽仁脂肪含量的生理基础.

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^[15,16] ...

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^[15,16] ...

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^[17,18,19] ...

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^[17,18,19] ...

2004

0.0

吴凯朝, 叶燕萍, 李杨瑞, 李永健, 杨丽涛. 喷施乙烯利对甘蔗群体冠层结构及一些抗旱性生理指标的影响. 西南农业学报, 2004, 17: 724-729

Wu K

, Ye Y

, Li Y

, Yang L

. Effects of spraying ethephon on the canopy structure and the physiological indexes for drought resistance in sugarcane. Southwest China J Agric Sci, 2004, 17: 724-729 (in Chinese with English abstract)

选用GT11和ROC20两个甘蔗品种为供试材料,在甘蔗伸长初期喷施100 mg/ L乙烯利,着重研究乙烯利对两个甘蔗品种一些抗旱性生理指标及工艺成熟期群体冠层结构的影响.结果表明,在干旱胁迫下乙烯利处理有利于优化工艺成熟期甘蔗群体冠层结构;提高甘蔗叶片束缚水含量和束缚水/ 自由水比值及维持其稳定性,提高了两个甘蔗品种的脯氨酸含量及综合抗旱能力;保持甘蔗叶片叶绿素含量的相对稳定性,改善GT11甘蔗品质.

... 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^[17,18,19] ...

2009

0.0

刘剑锋, 程云清, 陈智文. 乙烯对旱后复水玉米某些生理特性的影响. 热带亚热带植物学报, 2009, 17: 146-151

Liu J

, Cheng Y

, Chen Z

. Effects of Ethylene on some physiological characteristics of maize at rehydration after drought dress. J Trop Subtrop Bot, 2009, 17: 146-151 (in Chinese with English abstract)

The effects of ethylene on some physiological characteristics of maize (Zea mays L.) ‘Zhengdan 958’ cultured in pot at rehydration after drought stress were studied. The results showed that the biomass, relative water content, contents of chlorophyll and soluble protein, activities of nitrate reductase (NR) and glutamine synthetase (GS) in leaves enhanced treated with ethephon before rehydration, while the biomass, relative water content, soluble protein content, activities of NR and GS in seedlings reduced treated with AgNO3 significantly. After rehydration, the biomass, contents of chlorophyll and soluble protein in seedlings treated with ethephon were significantly higher than that of control treatment, while relative water content, NR and GS activities were closer to control treatment. But the biomass, soluble protein content decreased treated by AgNO3, and there were little effects on relative water content, NR and GS activities. So, spraying ethephon could promote maize seedlings resistant to drought.

研究了在不同水分条件下盆栽的玉米(Zea mays L.)品种‘郑单958’幼苗，经乙烯利和AgNO3处理，其对复水前后某些生理特征的变化。结果表明：复水前，在不同程度干旱胁迫下施用乙烯利有利于增加玉米的生物量、叶片相对含水量、总叶绿素含量、可溶性蛋白质含量、叶片硝酸还原酶(NR)活性和谷氨酰胺合成酶(GS)活性；而AgNO3处理明显降低生物量、叶片相对含水量、可溶性蛋白质含量、NR活性和GS活性。复水后，乙烯利处理的玉米生物量、总叶绿素含量、可溶性蛋白质含量明显高于对照，叶片相对含水量、NR和GS活性与对照相近；经轻度与重度干旱后复水，AgNO3处理明显降低玉米生物量和可溶性蛋白含量，对叶片相对含水量、NR、GS活性影响不明显。因此，施用乙烯利有利于提高干旱后复水条件下苗期玉米对干旱的抗性。

... 在干旱逆境条件下, 叶面喷施乙烯利可以提高叶片NR和GS活性, 提高玉米总叶绿素含量^[20] ...

... 乙烯利具有提高玉米叶片NR活性作用^[20], 而ECK主成分是乙烯利, 因而ECK处理后提高了NR活性和GS活性, 促进氮素同化作用, 进而提高了叶片中叶绿素、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 ...

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(2): 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(2): 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、抗倒伏和抗逆境胁迫方面效果显著^[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氮素同化过程及抗早衰效果的研究, 尤其是调控氮素代谢关键酶活性变化以及氮素同化效果方面的研究, 尚未见报道 ...

... 进一步分析发现, ECK处理能够提高密植群体下玉米抗氧化系统酶活, 降低活性氧产生速率, 提高叶绿素含量, 提高玉米抗逆性^[21,22,23] ...

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。

... 进一步分析发现, ECK处理能够提高密植群体下玉米抗氧化系统酶活, 降低活性氧产生速率, 提高叶绿素含量, 提高玉米抗逆性^[21,22,23] ...

2000

0.0

... 参考李合生^[23]的磺胺比色法测定硝酸还原酶(NR)活性 ...

... 进一步分析发现, ECK处理能够提高密植群体下玉米抗氧化系统酶活, 降低活性氧产生速率, 提高叶绿素含量, 提高玉米抗逆性^[21,22,23] ...

0.0

... 参照王学奎^[24]的方法测定谷氨酰胺合成酶(GS)活性, 以540 nm处吸光度的上升值间接表示酶活性 ...

1998

0.0

... 参考吴良欢等^[25]的方法测定谷草转氨酶(GOT)、谷丙转氨酶(GPT)活性, 以每克植物鲜样在30 min内反应生成的丙酮酸量(#cod#x000b5 ...

2002

0.0

... 采用考马斯亮蓝G-250染色法测定^[26] ...

1985

0.0

... 采用茚三酮比色法测定^[27] ...

2009

0.0

沈学善, 李金才, 屈会娟, 魏凤珍, 王成雨. 种植密度对晚播冬小麦氮素同化积累分配及利用效率的影响. 中国农业大学学报, 2009, 14: 41-46

Shen X

, Li J

, Qu H

, Wei F

, Wang C

. Effects of planting density on assimilation, accumulation, distribution and use efficiency of nitrogen in late sowing winter wheat. J Chin Agric Univ, 2009, 14: 41-46 (in Chinese with English abstract)

研究了种植密度对晚播小麦氮素同化积累分配及氮素利用效率的影响.以重穗型冬小麦品种兰考矮早八为材料,在晚播期(10-24-10一26)设低(150 万株/hm2)、中(225万株/hm2)、高(300万株/hm2)3个种植密度进行了2年大田试验.传统播期(10-10-10-12)为对照.结果表明,晚播小麦旗叶的硝酸还原酶活性和可溶性蛋白含量显著提高,单茎氮素积累量、营养器官转移氮素对籽粒氮素积累的贡献率以及植株的氮素收获指数和氮素吸收效率均提高,而氮素利用效率和籽粒产量降低.对照播期的低、中密度处理的氮代谢酶活性、氮素积累量和氮素利用效率及籽粒产量较高,而晚播处理则以中、高密度处理较高.不同播期的中密度处理的蛋白质含量和籽粒产量高于其他2个密度处理.因此,晚播条件下兰考矮早八兼顾高产和高效利用氮素的适宜播种密度为 225~300万株/hm2.

... 研究发现, 增加种植密度显著影响冬小麦、黑小麦和大豆氮素吸收、同化和分配^[28,29,30] ...

2011

0.0

张晓艳, 郑殿峰, 冯乃杰, 李建英, 杜吉到. 密度对大豆群体碳氮代谢相关指标及产量、品质的影响. 干旱地区农业研究, 2011, 29: 128-132

Zhang X

, Zheng D

, Feng N

, Li J

, Du J

. Effect of plant density on soybean carbon and nitrogen metabolism, yield and quality. Agric Res Arid Areas, 2011, 29: 128-132 (in Chinese with English abstract)

以垦农4号大豆为试验材料,在大田条件下,研究了密度对大豆群体碳氮代谢相关指标及产量品质的影响.结果表明,群体单株叶片氮素、可溶性蛋白、淀粉及蔗糖积累量均随着密度的增加而下降,低密度与高密度群体间差距显著;随着种植密度的增加,大豆子粒中蛋白质的含量有所上升,脂肪的含量有所下降;各生育时期氮素、可溶性蛋白、淀粉和蔗糖积累量与子粒蛋白质含量呈负相关,与脂肪含量呈正相关;随着种植密度的增加,群体内单株的荚数、粒数、粒重逐渐减少.在密度36万株/hm 时,群体产量最高.

... 研究发现, 增加种植密度显著影响冬小麦、黑小麦和大豆氮素吸收、同化和分配^[28,29,30] ...

2010

0.0

李晶, 吉彪, 商文楠, 陈龙涛, 魏玲, 魏湜. 密度和氮素水平对小黑麦氮代谢相关酶活性和子粒营养品质的影响. 植物营养与肥料学报, 2010, 16: 1063-1068

, Ji

, Shang W

, Chen L

, Wei

. Effects of density and nitrogen on relevant enzyme activity of nitrogen metabolism and nutritional quality of grain in triticale. Plant Nutr Fert Sci, 2010, 16: 1063-1068 (in Chinese with English abstract)

Effects of different densities and nitrogen levels on activities of nitrogen metabolism enzymes in flag leaf and grain quality were studied using triticale variety cv. Dongnong 5305. The results showed that the activities of nitrate reducase(NR) and glutamine synthetase(GS) of flag leaves increased, while endopeptidase and aminopeptidase of flag leaves decreased, and the soluble protein contents of flag leaves increased with the decreasing of density and increase of nitrogen fertilizer. Grain yield under density of 3 million/ha and N 75 kg/ha was higher than other treatments. Under density of 3 million/ha and N 150 kg/ha, contents of protein, amino acid and lysine of grain were the most. There was significant positive correlation between grain protein content and GS activities of flag leaves, while there was negative correlation with grain protein content and proteolytic activities. By reducing the density and increasing nitrogen fertilizer, the nitrogen assimilation of leaf after flowering was improved, the ability of leaf protein degradation was depressed, and leaf senescence was delayed. To the effect, we concluded that soluble protein content of flag leaves could be used as a physiological index for protein metabolism.

以小黑麦品种东农5305为试材，研究了不同密度和施氮水平对旗叶氮代谢相关酶活性和子粒品质的影响。结果表明，随着密度的降低、氮肥的施用，旗叶硝酸还原酶活性和谷氨酰胺合成酶活性提高，内肽酶和氨肽酶活性降低，可溶性蛋白含量增加; 密度300×104株/hm 2 、施氮75 kg/hm 2 处理子粒产量显著高于其它处理，密度300×10 4 株/hm 2 、施氮150 kg/hm 2 处理子粒蛋白质含量、氨基酸含量、赖氨酸含量最高。成熟期子粒蛋白质含量与生育期间旗叶谷氨酰胺合成酶活性显著正相关，与蛋白水解酶活性呈负相关。降低密度和增施氮肥，花后叶片的氮素同化能力增强，叶片蛋白质的降解能力减弱，延缓了叶片早衰。表明小黑麦旗叶可溶性蛋白含量可作为衡量蛋白质代谢的生理指标。

... 研究发现, 增加种植密度显著影响冬小麦、黑小麦和大豆氮素吸收、同化和分配^[28,29,30] ...

2012

0.0

... NR催化硝酸盐还原成亚硝酸盐, 调控氮素同化的第一步, 是植物氮代谢的限速酶, 其活性高低是氮代谢水平的直接反映^[31] ...

2002

0.0

... 该过程所生成的谷氨酸则在GOT和GPT等催化下转化为天门冬氨酸、丙氨酸等其他氨基酸, 为籽粒蛋白合成代谢提供各种氨基酸供体^[32,33,34] ...

2005

0.0

... 该过程所生成的谷氨酸则在GOT和GPT等催化下转化为天门冬氨酸、丙氨酸等其他氨基酸, 为籽粒蛋白合成代谢提供各种氨基酸供体^[32,33,34] ...

2009

0.0

... 该过程所生成的谷氨酸则在GOT和GPT等催化下转化为天门冬氨酸、丙氨酸等其他氨基酸, 为籽粒蛋白合成代谢提供各种氨基酸供体^[32,33,34] ...

2009

0.0

肖启银, 任万军, 杨文钰, 卢庭启, 刘代银. 免耕留茬抛秧栽培模式对水稻生育后期叶片衰老特性的影响. 作物学报, 2009, 35: 1562-1567

Xiao Q

, Ren W

, Yang W

, Lu T

, Liu D

. Effect of cultivation method of broadcasting rice seedlings in the field with stand ing-stubbles under no-tillage condition on senescence characteristics of leaves during late stages of rice development. Acta Agron Sin, 2009, 35: 1562-1567 (in Chinese with English abstract)

Three panicle types of hybrid rice combinations Fuyou I, D you 527, and Gangyou 881 were used to investigate the effects of different tillage and cultivation methods on the senescence characteristics and mechanism in middle and latter periods of rice. The results showed that, the SPAD value and soluble protein content (SPC) of leaf after heading were increased by the treatment of broadcasting rice seedlings in the field with standing-stubbles under no-tillage condition (BSNT). Activity of peroxidase (POD) was decreased, but activities of superoxide dismutase (SOD) and catalase (CAT) in the late growth duration (21 days after heading) were enhanced by the treatment of BSNT. For BSNT, rate of reactive oxygen free radical (O 2 ? ) production speed and malondialdehyde (MDA) content were lower than those for other treatments. Therefore, treatment of BSNT effectively delayed senescence of plant.

以穗型差异较大的 3 个杂交稻组合富优 I 号、 D 优 527 、冈优 881 为材料，研究了不同栽培方式下水稻生育中后期叶片的衰老特性及机制。结果表明，免耕留茬抛秧提高了水稻抽穗后叶片的 SPAD 值和可溶性蛋白含量，降低了叶片的 POD( 过氧化物酶 ) 活性，提高了生育后期 ( 抽穗 21 d 后 ) 叶片的 SOD( 超氧化物歧化酶 ) 和 CAT( 过氧化氢酶 ) 活性， 3 种酶协同作用，降低了活性氧自由基产生速率和 MDA( 丙二醛 ) 含量，从而延缓了植株衰老。

... 游离氨基酸含量、可溶性蛋白含量和叶绿素含量是指示叶片早衰的直接指标, 且各项指标之间密切相关^[35] ...

2010

0.0

马超, 黄晓书, 李鹏坤, 卫丽. 种植密度对夏玉米果穗叶生理功能衰退的影响. 玉米科学, 2010, 18(2): 50-53

, Huang X

, Li P

, Wei

. Effects of planting density on physiological decline on ear leaf of summer maize. J Maize Sci, 2010, 18(2): 50-53 (in Chinese with English abstract)

以郑单958为供试品种,在大田条件下研究不同种植密度对夏玉米果穗叶生理功能衰退特性的影响.结果表明:果穗叶叶绿素a+b含量、原初光化学效率(F_v/F_m)、光系统Ⅱ(PSⅡ)潜在活性(F_v/F_o)、可溶性蛋白、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性均随果穗叶功能期的推进呈下降趋势,且随密度的增大下降趋势明显,吐丝后39d下降最显著;果穗叶叶绿素a/b、丙二醛(MDA)含量呈逐渐上升趋势.随着种植密度的增大,果穗叶光能转化和自身保护酶系活性下降,光合生产能力减弱,造成果穗叶生理功能早衰,缩短了叶片功能期. Abstract： Taking Zhengdan958 as material, six density levels were designed to investigate the effects of different planting density on physiological decline on ear leaf of summer maize.The results showed that with ear leaf functional stage developing, Chl(a+b), maximum photo-chemical efficeiency(F_v/F_m), PS Ⅱ potential activity(F_v/F_o), light-saturated photosynthetic rate(Pnmax), apparent quantum yield(AQY), soluble protein content, SOD activity,CAT activity all took on decline tendency, and they were decreased with density increasing, especially after silking 39 days.Chl(a/b), MDA content showed a gradually increase tendency.The increasing of cultivation density leaded to the decline of ear leaf physiological function and self-guard enzyme activity and eventually shortening leaf functional stage, decreasing its photosynthesis.

... 研究表明, 增加种植密度导致叶片可溶性蛋白含量和叶绿素含量下降^[36], 本研究结果发现, 游离氨基酸、可溶性蛋白和叶绿素含量与密度在灌浆前期(花后0~10 d)相关性较小 ...

... 本研究发现, 增加种植密度导致叶片NR、GS、GOT和GPT活性降低, 导致叶片叶绿素和可溶性蛋白含量降低^[36], 诱导叶片早衰, 最终导致产量下降^[13,40] ...

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。

... 这可能与灌浆中后期高密群体叶片NR^[37]、GS、GOT和GPT活性降低, 营养器官中的含氮物质降解, 以游离氨基酸的形式向籽粒中迅速转移有关 ...

... 产量与种植密度呈二次曲线关系^[38], 当超过适宜密度时, 光温水肥竞争导致群体恶化, 叶片早衰直接影响着籽粒灌浆过程, 最终影响产量和品质^[37] ...

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)

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.

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。

2007

0.0

杨亮, 赵宏伟, 刘锦红. 氮素用量对春玉米功能叶片谷氨酰胺合成酶活性及产量的影响. 东北农业大学学报, 2007, 38: 320-324

Yang

, Zhao H

, Liu J

. Effects of different nitrogen application on GS activity and yield in different quality spring maize varieties. J Northeast Agric Univ, 2007, 38: 320-324 (in Chinese with English abstract)

试验以东农250、四单19、丰禾10为材料,研究了不同氮素用量对黑龙江省春玉米谷氨酰胺合成酶活性影响,揭示了不同氮素用量对春玉米氮代谢及产量的影响.结果表明,①玉米功能叶片谷氨酰胺合成酶活性峰值出现在孕穗期或抽雄期;②三个品种整个生育过程中各处理功能叶片谷氨酰胺合成酶活性均以N200处理较高,对三个品种来说,N200处理是最佳的氮素处理;③在拔节后各处理谷氨酰胺合成酶活性快速升高并相继达到峰值,拔节前追肥可促进后期谷氨酰胺合成酶活性提高;④七叶期和成熟期叶片谷氨酰合成酶活性与子粒产量呈显著正相关.

... 本研究发现, 增加种植密度导致叶片NR、GS、GOT和GPT活性降低, 导致叶片叶绿素和可溶性蛋白含量降低^[36], 诱导叶片早衰, 最终导致产量下降^[13,40] ...