首页关于本刊影响因子及获奖投稿须知订阅及广告专辑与专题学术会议绿色发表通道优秀论文 
说明:
此论文已被《生态学报》录用,现已优先出版,可查看文章PDF版本!
冯晓钰,周广胜.夏玉米叶片水分变化与光合作用和土壤水分的关系.生态学报,2018,(1).http://dx.doi.org/10.5846/stxb201612092534  
夏玉米叶片水分变化与光合作用和土壤水分的关系
Relationship of leaf water content with photosynthesis and soil water content in summer maize
投稿时间:2016-12-09  修订日期:2017-07-30
DOI: 10.5846/stxb201612092534
关键词夏玉米  净光合速率  叶片含水量  土壤含水量
Key Wordssummer maize  net photosynthetic rate  leaf water content  soil water content
基金项目国家自然科学基金项目(重点项目)公益性行业(气象)科研专项(重大专项)
作者单位E-mail
冯晓钰 中国气象科学研究院 zjpjfxy@163.com 
周广胜 中国气象科学研究院 gszhou@camcma.cn 
摘要点击次数 154
全文下载次数 31
摘要:
叶片是光合作用的重要器官,其含水量的变化必将影响光合作用,但关于叶片水分变化对光合作用的影响报道较少。以华北夏玉米为研究对象,利用三叶期不同水分梯度的持续干旱模拟试验资料,分析夏玉米叶片水分变化及其与叶片净光合速率和土壤水分的关系。结果表明:夏玉米叶片净光合速率对叶片水分变化的响应显著且呈二次曲线关系,叶片含水量约为70.30%时,叶片净光合速率为零;叶片含水量与土壤相对湿度呈非直角双曲线关系,叶片最大含水量约为85.14%。研究结果可为准确描述叶片水分变化对光合作用的影响及客观辨识夏玉米干旱的发生发展及监测预警提供参考。
Abstract:
Because leaves are the chief organs of photosynthesis, changes in leaf water content affect photosynthesis. Leaf water content can directly reflect crop growth and development, and indirectly reflect the degree of atmospheric drying, ability of soil to supply water, and drought tolerance of crops. Until now, soil water content and its effects on plant photosynthetic parameters have been investigated in numerous studies, but the influence of leaf water content on photosynthesis has not yet been reported. Estimation of this influence is essential for accurate simulation of photosynthesis. In this study, summer maize from north China, which suffers from frequent droughts, was used to determine the relationship of leaf water content with net photosynthetic rate (P_n) and soil water content, by performing water manipulation experiments using 3-leaf stage plants. On the basis of the average monthly natural precipitation for July, over 30 years from 1981 to 2010, in Baoding, Hebei Province, six watering treatments (7%, 20%, 40%, 60%, 80%and 100%) were used, with three replicates per treatment. The watering treatments with disposable irrigation were used to simulate the effects of consecutive droughts of different intensities on the photosynthetic characteristics of summer maize. The plants were not watered after July 2. The soil water content, fresh weight and dry weight of leaves, and net photosynthetic rate (on the same leaf on the same plant) were measured under sunny weather conditions every 1 to 2 weeks. The different watering intensities strongly affected the crop index of summer maize. The results indicated that the leaf water content of summer maize significantly affected the net photosynthetic rate, the two factors showed a quadratic curve relation under all weather conditions or developmental stages of plant growth, but with different curve coefficients. On an average, P_n reduced to zero when the leaf water content reached approximately 70.3%, this was considered as an important threshold in the photosynthetic physiological activity of leaves. It can provide the basis for dynamic monitoring of large-scale drought development and accurate assessment of drought degree in crops. Moreover, leaf water content showed a non-rectangular hyperbolic relationship with soil moisture, which differs from the linear relationship reported in the previous studies, because of the narrow water gradient. The leaf water content increased with increasing relative soil water content and then tended to plateau, which is called the leaf water holding capacity. According to the Michaelis-Menten equation, the maximum leaf water content was estimated to be 85.14%, using the double reciprocal Lineweaver-Burk plot. The leaf water holding capacity and the critical leaf water content are different for different crops; however, a consistency in the research methods and laws of response may provide a reference for understanding the effect of changes in leaf water content on photosynthesis. These results could contribute to objective identification of the occurrence and development of drought events in summer maize.
HTML 查看全文   查看/发表评论  下载PDF阅读器

您是本站第 65583341 位访问者

Copyright © 2005-2019   京ICP备06018880号
地址:北京海淀区双清路18号
  邮编:100085    电话:010-62941099
  E-mail : shengtaixuebao@rcees.ac.cn
本系统由北京勤云科技发展有限公司提供技术支持