中国农业科学 ›› 2017, Vol. 50 ›› Issue (11): 2093-2103.doi: 10.3864/j.issn.0578-1752.2017.11.015

所属专题: 玉米栽培研究专刊

• 逆境生理与抗逆栽培 • 上一篇    下一篇

生育前期淹水对夏玉米冠层结构和光合特性的影响

任佰朝,张吉旺,董树亭,赵斌,刘鹏   

  1. 山东农业大学农学院/作物生物学国家重点实验室,山东泰安 271018
  • 收稿日期:2016-08-01 出版日期:2017-06-01 发布日期:2017-06-01
  • 联系方式: 任佰朝,Tel:15966019130;E-mail:renbaizhao@sina.com
  • 基金资助:
    “973”计划项目(2015CB150404)、国家现代农业产业技术体系建设项目(CARS-02-20)、山东省农业重大应用技术创新项目

Effect of Waterlogging at Early Period on Canopy Structure and Photosynthetic Characteristics of Summer Maize

REN BaiZhao, ZHANG JiWang, DONG ShuTing, ZHAO Bin, LIU Peng   

  1. College of Agronomy, Shandong Agricultural University/State Key Laboratory of Crop Biology, Taian 271018, Shandong
  • Received:2016-08-01 Published:2017-06-01 Online:2017-06-01

摘要: 【目的】本研究旨在探讨大田淹水条件下夏玉米冠层结构和光合特性的变化规律。【方法】供试夏玉米品种为登海605(DH605)和郑单958(ZD958),通过设置3叶期(V3)淹水3 d(V3-3)和6 d(V3-6),拔节期(V6)淹水3 d(V6-3)和6 d(V6-6),以不淹水处理为对照(CK),比较不同淹水时期(V3和V6)和淹水持续时间(3 d和6 d)对夏玉米光合势、叶面积指数、净光合速率、冠层透光率及其半球灰度图像和产量的影响。【结果】淹水后夏玉米叶面积指数显著下降,群体透光率提高,群体光能截获率显著降低。V3淹水后夏玉米穗位层和底层透光率的提高幅度大于V6淹水,且其提高幅度随淹水持续时间的延长而增加。DH605和ZD958的V3-6处理的穗位层透光率较CK分别提高96.0%和70.2%,底层透光率分别提高了68.9%和71.9%。在淹水胁迫条件下夏玉米光合势和叶片净光合速率随淹水持续时间的延长而显著降低,V3淹水后净光合速率和光合势的下降幅度大于V6淹水。DH605和ZD958的V3-6处理在开花期的叶片净光合速率较CK分别下降23.5%和20.3%。DH605的V3-6处理在播种—拔节期、拔节期—大喇叭口期、大喇叭口期—开花期、开花期—乳熟期和乳熟期—成熟期各生育阶段的光合势较CK分别下降68.5%、45.0%、31.6%、25.0%和37.5%,ZD958分别下降62.4%、37.1%、25.8%、21.7%和38.5%。淹水后夏玉米光合势和叶片净光合速率的下降导致夏玉米光合同化物的积累与分配受到抑制,干物质积累量显著下降,成熟期DH605的V3-3、V3-6、V6-3和V6-6处理的干物质重较CK分别下降12.4%、24.8%、9.3%和21.1%,ZD958分别下降17.3%、26.7%、12.5%和23.9%。此外,淹水后夏玉米收获指数显著下降,3叶期淹水对其影响大于V6淹水,且影响随淹水持续时间的延长而加剧,DH605和ZD958的V3-6处理的收获指数较CK分别下降13.3%和13.8%。淹水后夏玉米冠层结构劣化与光合性能降低导致夏玉米产量显著下降。DH605的V3-3、V3-6、V6-3和V6-6处理的产量较CK分别下降23.2%、35.9%、17.0%和22.7%,ZD958分别下降20.0%、35.7%、15.0%和27.1%。【结论】淹水导致夏玉米群体光合势和叶面积指数显著降低,透光率提高,进而显著降低群体光能有效截获率和净光合速率,最终导致夏玉米产量显著下降。3叶期淹水对夏玉米冠层结构和光合特性的影响大于拔节期淹水,且其影响随淹水持续时间的延长而加剧。

关键词: 夏玉米, 淹水胁迫, 透光率, 净光合速率, 籽粒产量

Abstract: 【Objective】 The objective of this study is to investigate the effects of waterlogging on canopy structure and photosynthetic characteristics of summer maize under field conditions. 【Method】 Two summer maize cultivars Denghai605 (DH605) and Zhengdan958 (ZD958) were used as experimental materials. Experimental treatments consisted of waterlogging at the third leaf stage for 3 d (V3-3) and for 6 d (V3-6), waterlogging at the sixth leaf stage for 3 d (V6-3) and for 6 d (V6-6), and no waterlogging (CK). The field experiment was performed to explore the effects of waterlogging for different durations (3 and 6 days) on photosynthetic intensity, net photosynthetic rate, canopy light transmittance and its hemispheric gray images, and grain yield of summer maize at the third leaf stage (V3) and sixth leaf stage (V6). 【Result】 Results showed that leaf area index was significantly reduced after waterlogging. Waterlogging significantly increased group light transmittance, and led to a remarkable reduction of light interception rate. Group light transmittance of summer maize was more susceptible to waterlogging damage at V3, followed by V6, and damage was increased with the increasing waterlogging duration. The light transmittances of ear layer were increased by 96.0% and 70.2% for V3-6 in DH605 and ZD958, respectively, compared to CK. That ground floor increased by 68.9% and 71.9% for V3-6 in DH605 and ZD958, respectively, compared to CK. Waterlogging significantly decreased group photosynthetic potential (LAD) and net photosynthetic rate (Pn);The most decrease of Pn of two hybrids was found at V3-6, with 23.5% and 20.3% in DH605 and ZD958, respectively. LAD of V3-6 for DH605 was decreased by 68.5%, 45.0%, 31.6%, 25.0%, and 37.5% at seedling-V6, V6-the twelfth leaf stage (V12), V12-the flowering stage (VT), VT-the milking stage (R3), and R3-the physiological maturity stage (R6), respectively. ZD958 decreased by 62.4%, 37.1%, 25.8%, 21.7%, and 38.5%, respectively. The reduction of LAD and Pn led to the decrease of photoassimilates. Dry matter weight of V3-3, V3-6, V6-3, and V6-6 for DH605 was decreased by 12.4%, 24.8%, 9.3%, and 21.1%, ZD958 decreased by 17.3%, 26.7%, 12.5%, and 23.9%, respectively. In addition, waterlogging decreased harvest index, with the most significant reduction in V3-6 with a decrease of 13.3% and 13.8% for DH605 and ZD958. The degradation of canopy structure and photosynthetic characteristics resulted in a significant reduction of maize yield after waterlogging. Grain yield of V3-3, V3-6, V6-3, and V6-6 for DH605 was decreased by 23.2%, 35.9%, 17.0%, and 22.7%, ZD958 decreased by 20.0%, 35.7%, 15.0%, and 27.1%, respectively. 【Conclusion】 Waterlogging significantly decreased leaf area index and ground photosynthetic potential, led to the reduction of light interception rate and photosynthetic performance, decreasing net photosynthetic rate, eventually resulted in a remarkable reduction of summer maize yield. Canopy structure and photosynthetic characteristics of summer maize was more susceptible to waterlogging damage at V3, followed by V6, damage was increased with the increasing waterlogging duration.

Key words: summer maize, waterlogging, light transmission, net photosynthetic rate, grain yield