| 摘要: |
| 为探索干旱胁迫对甜菜块根膨大期叶片光合作用光响应特性的影响,以H1352、81GM26甜菜品种为材料,设置两个灌水处理,通过对叶片净光合速率与光强响应曲线的模拟得出最大净光合速率(Pnmax)、暗呼吸速率(Rd)、表观量子效率(AQY)、光补偿点 (LCP)和光饱和点(LSP)主要光合参数。结果表明,H1352、81GM26甜菜品种叶片Pn均随着PAR的增大先呈线性增加,后急速增大,最终渐趋平稳或下降,H1352干旱胁迫处理净光合速率(Pn)表现出明显光抑制现象；在不同PAR条件下,两品种Pn总是对照大于干旱胁迫处理,且随PAR的增大差异愈明显。干旱胁迫极显著降低叶片最大净光合速率和光饱和点(P<0.01)。H1352和81GM26品种在干旱胁迫条件下最大净光合速率分别为24.8μmol.m<sub><sup>-2</sup></sub>.s<sub><sup>-1</sup></sub>和21.0μmol.m<sub><sup>-2</sup></sub>.s<sub><sup>-1</sup></sub>,分别比对照低18%和26%；光补偿点分别为600μmol.m<sub><sup>-2</sup></sub>.s<sub><sup>-1</sup></sub>和601μmol.m<sub><sup>-2</sup></sub>.s<sub><sup>-1</sup></sub>,分别比对照低18.5%和16.4%,叶片光适应范围变窄,光能利用能力降低。H1352品种在干旱胁迫条件下叶片暗呼吸速率极显著降低,比对照降低40.3%,而81GM26品种处理间没有显著差异。甜菜块根膨大期遭遇干旱胁迫,将影响叶片光合生产能力,光能吸收利用效率降低,要及时补水。 |
| 关键词: 甜菜;光合作用光响应;块根膨大期;干旱胁迫 |
| DOI： |
| 分类号:S562 |
| 基金项目:：参与国家糖料产业技术体系(CARS-170723) |
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| Effects of Drought Stress on Photosynthetic Characteristics of Photosynthesis during Sugarcane Root Expansion |
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Wang Ke-zhe, DU YA MIN, Hou Li Li
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YiNing Prefecture Institute of Agricultural Sciences,Yining
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| Abstract: |
| In order to explore the effects of drought stress on photosynthesis photosynthetic characteristics of sugar beet root during expansion period, two irrigation treatments were set up with H1352 and 81GM26 sugar beet varieties, and the simulation results showed that the net photosynthetic rate and light intensity response curves of leaves were simulated. Maximum net photosynthetic rate (Pnmax), dark respiration rate (Rd), apparent quantum efficiency (AQY), light compensation point (LCP) and light saturation point (LSP) are the main photosynthetic parameters. The results showed that the Pn of leaves of H1352 and 81GM26 beeta increased linearly with the increase of PAR, then increased rapidly and eventually became stable or decreased. The net photosynthetic rate (Pn) of H1352 drought stress showed obvious photoinhibition. Under different PAR conditions, the two varieties of Pn were always treated with greater than drought stress, and the difference was more obvious with the increase of PAR. Drought stress significantly reduced the maximum net photosynthetic rate and light saturation point of the leaves (P<0.01). The maximum net photosynthetic rates of H1352 and 81GM26 under drought stress were 24.8μmol.m-2.s-1 and 21.0μmol.m-2.s-1, respectively, which were 18% and 26% lower than the control, respectively; They were 600μmol.m-2.s-1 and 601μmol.m-2.s-1, respectively, which were 18.5% and 16.4% lower than the control, respectively. The light adaptation range of the leaves was narrowed and the light energy utilization ability was reduced. Under the drought stress condition, the dark respiration rate of H1352 varieties decreased significantly, which was 40.3% lower than that of the control, while there was no significant difference between the treatments of 81GM26 varieties. The drought stress of beet roots will affect the photosynthetic capacity of the leaves, and the efficiency of light energy absorption and utilization will be reduced. |
| Key words: sugar beet; photosynthesis response; root enlargement period; drought stress |
