摘要: |
应用CIRAS-2型光合测定系统,在人为浇水至土壤饱和后的自然耗水干旱过程中,测定了2年生盆栽蔷薇Rosa multiflora 光合作用的CO2响应过程,采用指数改进模型对其响应过程进行拟合。结果表明:维持蔷薇光合作用较高水平的土壤相对含水量(RWC)范围在43.8%~84.9%之间,最适宜的RWC在64.4%左右,维持蔷薇光合作用最低RWC在18.3%左右。蔷薇平均净光合速率(Pn)、羧化效率(CE)、光合能力(Pnmax)随RWC增加呈“升缓降陡”的抛物线形变化趋势,几项参数受淹涝胁迫时的下降趋势要快于受干旱胁迫时的下降趋势,表明蔷薇具有耐旱不耐涝的光合生理特征。 |
关键词: 土壤水分 蔷薇 光合作用 CO2响应 |
DOI: |
分类号: |
基金项目: |
|
CO2 Response Process of Rosa multiflora Photosynthesis in the Process of Gradual Soil Water Loss |
CHEN Jian1,2, XING Xianshuang1,2, DONG Mingming1,2, ZHANG Mingquan1,2
|
1.Shandong Hydrology Bureau,Jinan,250002;2.china.
|
Abstract: |
Using CIRAS-2 photosynthetic system, the CO2 response of 2-year-old Rosa multiflora photosynthesis was measured during natural water consumption drought from artificial watering to soil saturation. The CO2 response process of R. multiflora were fitted by modified exponential model. The results showed that the RWC range of maintaining the higher level of photosynthesis of R. multiflora was between 43.8% and 84.9%, the most suitable RWC was about 64.4%, and the lowest RWC of maintaining photosynthesis of R. multiflora was about 18.3%. The average net photosynthetic rate (Pn), carboxylation efficiency (CE) and photosynthetic capacity (Pnmax) of R. multiflora showed a parabolic trend of “Slow rise and steep fall” with the increase of RWC. The downward trend of physiological parameters under waterlogging stress was faster than that under drought stress, indicating that rose had the photosynthetic physiology characteristics of drought tolerance but not waterlogging tolerance. |
Key words: soil water content Rosa multiflora photosynthesis CO2 response |