干旱胁迫对黄秋葵幼苗生长以及叶片光合特性的影响

通过PEG模拟干旱胁迫,初步研究干旱胁迫对黄秋葵幼苗生长及叶片光合特性的影响。结果显示:2个品种的叶柄长、株高、茎粗、根长、苗鲜重、苗干重、最大叶长、最大叶宽、功能叶面积以及抗旱系数均随着PEG浓度的增加而减少,表明干旱胁迫抑制了黄秋葵幼苗的生长,随着干旱胁迫程度的增加,其抗性逐渐减弱;2个品种叶片的净光合速率、气孔导度均随PEG浓度的增加而减少,说明干旱胁迫抑制了黄秋葵的光合能力。相关性分析表明,黄秋葵叶柄长、株高、茎粗、根长、苗鲜重、苗干重、最大叶宽、最大叶长、净光合速率、气孔导度均与抗旱系数极显著相关,说明相关性状及生理生化指标可作为干旱胁迫下黄秋葵幼苗的抗旱性鉴定指标。

Effect of Drought Stress on Seedling Growth and Leaf Photosynthetic Traits of Okra

Okra seedlings were treated under drought stress simulated with different concentrations of PEG-6000 solutions to observe their growth and leaf photosynthesis. The results showed that the petiole length, plant height, root diameter, root length, seedling fresh weight, dry weight, the largest leaf width, the largest leaf length, functional leaf area per plant and drought-resistance index of okra were significantly decreased with an increase in concentration of PEG-6000 solution. This implied that the growth of okra seedlings was inhibited by drought stress. The resistance of the seedlings to drought stress decreased gradually with the increase of the drought stress. The photosynthetic rate and stomatal conductance also significantly decreased with the increase of the concentration of PEG-6000 solution. This suggested that photosynthesis of the seedlings was suppressed by drought stress. Correlation analysis showed that the petiole length, plant height, root diameter, root length, fresh weight, dry weight, the largest leaf width, the largest leaf length, the photosynthetic rate and stomatal conductance were highly significantly correlated to the drought resistance coefficient. These traits and physiological and biochemical indexes can be used as the indexes to identify drought resistance of okra seedlings under drought stress.