水分胁迫对金露梅叶片水势、光合特性和水分利用效率的影响  

Impact of water stress on leaf water potential,photosynthetic parameters and water use efficiency of Potentilla fruticosa

作　　者：刘颖[1] 贺康宁[1] 徐特[1] 王辉[1] 刘玉娟[1] 

机构地区：[1]北京林业大学水土保持与荒漠化防治教育部重点试验室,北京100083

出　　处：《中国水土保持科学》2016年第1期106-113,共8页Science of Soil and Water Conservation

基　　金：2014年青海省重大科技专项"柴达木盆地盐碱地造林技术研究与示范"(2014-NK-A4-4)

摘　　要：为解决青海高寒区绿化植物的栽培驯化问题,并为金露梅栽植的科学管理及高寒区水资源有效利用提供理论基础,以2年生金露梅幼苗为研究对象,通过盆栽方法人为控制土壤水分条件,测定不同土壤水分条件下金露梅苗木的光合生理特征,研究金露梅光合生理特性及其与土壤水分的相互关系。结果显示：1）金露梅凋萎系数为4.02%左右;2）土壤水分对金露梅叶水势及光合作用的影响具有阈值现象,净光合速率最大时土壤含水量为20.83%,水合补偿点为4.38%,水分利用效率最大时土壤含水量为13.82%;3）在砂壤土条件下,金露梅生长最适宜的土壤水分环境为8.33%~12.71%,此范围内既可以维持植物基本的生长所需,又可以最大程度提高水分利用效率;4）青海地区在金露梅盛花期（7月）,在无降雨的情况下,每2~3周补充一次水分能维持金露梅较好生长。2~3周的持续干旱所造成的伤害在灌水后可逐渐恢复,但连续1个月无任何供水会使金露梅死亡。[Background] The rapid development of urbanization have put forward higher requirements on the country road greening and landscape. But the high latitudes, low temperature and drought problem restrain the growth and breeding of many kinds of flowers in the cold and arid Qinghai Province. So a number of scholars began to study the advantages of the local wild species, trying to pick out plant species domesticated from local flowers for landscaping and road greening.[ Methods] In order to solve the problem of the cultivation and domestication of greening plants in the cold and arid Qaidam regions, Qinghai Province, explore the photosynthetic physiological characteristics of Potentilla fruticosa and its quantitative relations with soil moistures, provide a scientific basis to the scientific irrigation management of P. fruticosa, and improve the water use efficiency of alpine and arid regions in addition, 17 P. fruticosa seedlings （2 years old） were taken as the research object under a pot experiment to study its rules of response to drought stress and rewatering. Leaf water potential, photosynthetic parameters and photosynthetic diurnal variation process were investigated. Quantitative relations between net photosynthetic rate, transpiration rate, water use efficiency and soil water content were explored to determine the suitable soil moisture thresholds of photosynthesis and water use efficiency of P. fruticosa. [ Results ＆ Conclusions] The main results are as follows： 1 ） With the lowering of soil moisture to 5.97% , more than half of the leaves dried up, and the wilting moisture content of P. fruticosa was about 4.02%. 2） The effects of soil moisture content on leaf water potential and photosynthetic parameters had threshold, too high and too low soil moisture content would inhibit the physiological activity of P. fruticosa. The morning leaf water potential, net photosynthetic rate, and transpiration rate of P. fruticosa had obvious threshold response to the changes of soil moisture. The morning leaf

关 键 词：水分胁迫 叶片水势 光合作用 水分利用效率 土壤含水量 

分 类 号：S714[农业科学—林学]