| 摘要: |
| 通过盆栽试验，以抗旱性强弱不同的两个种源地文冠果为试验材料，对干旱胁迫下文冠果的光合生理指标进行较为系统的研究，结果表明：① 干旱胁迫条件下两个种源地文冠果叶片净光合速率（Pn）、气孔导度（Cond）、蒸腾速率（Tr）、叶绿素含量（Chl）都有不同幅度的下降。抗旱性强的文冠果（新疆喀什）随着干旱胁迫的加剧，净光合速率、气孔导度和叶绿素含量下降较慢。② 轻度干旱胁迫下气孔限制是影响两个种源地文冠果Pn下降的主要因素；中度和重度干旱胁迫下，非气孔限制是两个种源地文冠果Pn下降的主要因素。③ 叶绿素荧光参数研究表明：干旱胁迫条件下两个种源地文冠果PSⅡ反应中心光化学效率（Fv/Fm）、PSⅡ潜在活性（Fv/Fo）均降低；PSⅡ光化学淬灭系数（qP）均降低，而PSⅡ非光化学淬灭系数（qNP）则增大。总体上，与抗旱性弱的文冠果相比，抗旱性强的文冠果的i>Fv/Fm和Fv/Fo下降幅度较小，PSⅡ的光化学能力和PSⅡ潜在活性均较强；PSⅡ光化学淬灭系数（qP）降低的幅度较小且PSⅡ非光化学淬灭系数（qNP）降低幅度较大。 |
| 关键词: 文冠果 干旱胁迫 光合作用 荧光参数 |
| DOI： |
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| 基金项目:陕西省自然科学基础研究计划项目（2009JM3001） |
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| Photosynthetic physiological response of Xanthoceras sorbifolia under drought stress |
| WU Jia-bao1, MA Ming-ke2, ZHANG Gang1, WEI Dian-dian1, LIU Shu-ming1 |
| () |
| Abstract: |
| A pot-cultivation experiment was performed to investigate the photosynthetic physiology of X.sorbifolia under the drought stress. Two varieties of X.sorbifolia from different provenances were used to systematically study the phtotosynthetic physiology under the drought stress. The results showed that: (1) Under the drought stress, the net photosynthetic rate, stomatal conductance, transpiration rate and chlorophyll content decreased in varying degrees both in the leaves of X.sorbifolia Compared to X.sorbifolia from Yan′an, Shaanxi with the low drought-resistance, the net photosynthetic rate, stomatal conductance, transpiration rate and chlorophyll content decreased more slowly. In the leaves of X.sorbifolia from Kaishi, Xinjiang with high drought-resistance. (2) Under the light drought stress, stomatal restriction was the main factor for the Pn’s decreased in the leaves of both the two varieties of X.sorbifolia, while the non-stomatal restriction was the main factor for the Pn’decrease under the medium and severe drought stress. (3) The result of fluorescence experiment of PSⅡ Reaction Center indicated Fv/Fm and Fv/Fo decreased in both X.sorbifolia under the drought stress, the quenching of chlorophyll fluorescence (qP) decreased, and non-photochemical quenching of chlorophyll fluorescence(qNP) increased for both X.sorbifolia under the drought stress. In general, compared to X.sorbifolia with the low drought-resistance, Fv/Fm and Fv/Fo had a smaller decrease, qP had a smaller decrease and qNP had a bigger increase in the leaves of X.sorbifolia under the drought stress. |
| Key words: Xanthoceras sorbifolia drought-stress photosynthesis fluorescence parameter |
