黄土旱塬冬小麦水分利用效率及相关生理特性研究  

Study on Water Use Efficiency and Related Physiological Characteristics of Winter Wheat on Dryland of Loess Plateau

作　　者：戚龙海[1,2] 党廷辉[1] 陈璐[3] 

机构地区：[1]中国科学院水利部水土保持研究所,陕西杨凌712100 [2]中国科学院研究生院,北京100049 [3]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《中国农学通报》2009年第6期107-112,共6页Chinese Agricultural Science Bulletin

基　　金：中国科学院知识创新工程重要方向项目"旱作农田生态系统水氮耦合过程及碳库变化"(KZCX2-YW-424-2)

摘　　要：采用Li-6400便携式光合测定系统在模拟光照条件下,通过对冬小麦叶片生理指标及其相应环境因子的测定,研究了小麦的生理指标和叶片水分利用效率的动态变化规律及其对环境因子的响应。结果表明:净光合速率日变化呈不明显的双峰曲线,蒸腾速率日变化呈明显的倒"U"型曲线,且不同生育期两者峰值出现的时间不同。拔节期环境因子对生理指标的影响要比灌浆期明显的多。光合有效辐射和CO2浓度是对净光合速率和叶片蒸腾速率影响最强烈的环境因子。在小麦整个生长过程中,温湿度对气孔导度的影响在逐渐增大,对胞间CO2浓度的影响也比较明显。小麦叶片水分利用效率的日变化呈不明显的双峰曲线,其峰值出现的时间早于净光合速率和蒸腾速率峰值出现的时间。灌浆期日平均WUE比拔节期低30.5%。小麦净光合速率、蒸腾速率和气孔导度三者之间极显著相关,叶片温度与气孔导度显著负相关。With the aid of Licor-6400 portable photosynthesis system, the pnyslological indexes and related environmental factors were measured and influence of environmental factors on photosynthetic physiologic indexes and leaf water use efficiency of winter wheat was studied on dryland of Loess Plateau. The result showed that diurnal fluctuation of physiological rate（Pn） of leaf was a not obvious two-hump curve and that of transpiration rate（Tr） was a typical resupinate ＂U＂ . the Pn and Tr in a.m. were distinctly higher than in p.m., but the time at which the maxium appeared was different in different growth stage. The time of maxium appeared of Tr and Pn was same in elongation stage and the time of maxium appeared of Tr was later than that of Pn in grain filling stage. The effects of environmental factors on physiologic indexes in elongation stage was more obvious than that in grain filling stage. The most important environmental factors on Pn and Tr were photosynthetic active radiation（PAR） and CO2 concentration. The influence of Temperature （T） and relative humidity（RH） on stomatal conductance（Gs） was progressively increased and the influence on Intercellular CO2 concentration was obvious. The diurnal fluctuation of water use efficiency was a not obvious two-hump curve and the time of maxium appeared was earlier than those of Pn and Tr. The daily mean WUE in filling stage was lower than that in elongation stage to 30.5%. The correlations among Pn,Tr and Gs reached 1% significant level and there was a significant negative correlation between temperature of leaf and Gs.

关 键 词：黄土高原 冬小麦 光合 水分利用效率 环境因子 

分 类 号：S181[农业科学—农业基础科学]