Research on biosynthesis of UV absorbing substances in epidermis of plant leaves and their function to protect the plants from injury by UV radiation.

植物叶片表皮紫外线吸收物质的生物合成及其保护植物免受紫外线伤害的功能研究。

• 批准号: 63540543
• 负责人: KONDO Noriaki
• 金额: $ 1.41万
• 依托单位: The National Institute for Environmental Studies
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63540543/
• 关键词: Pea; Cucumber; Chlorosis; Glutathione reductase; UV absorbing substances; Growth retardation; UV-A; UVーB; 紫外線感受性; ス-パ-オキシドジスムタ-ゼ; Argenteum; クロロフィルa__-蛍光; 紫外線防御; ソラマメ; フラボノイド; UV-C; Pea; Cucumber; Chlorosis; Glutathione reductase; UV absorbing substances; Growth retardation; UV-A; UVーB; 紫外線感受性; ス-パ-オキシドジスムタ-ゼ; Argenteum; クロロフィルa__-蛍光; 紫外線防御; ソラマメ; フラボノイド; UV-C

Radiation of ultraviolet-B (UV-B) region (280-320nm) causes growth retardation of plants and visible injury such as chlorosis on leaf surface. These damages seem to be under the control of the environmental conditions during plant growth. The extent of damage is thought to depend on the differences of content of ultraviolet (UV) absorbing substances in the epidermis of plant leaves. In the present studies, the content of UV absorbing substances in leaf epidermis of pea mutant and broad bean was compared with resistance of these plants to ultraviolet-C (UV-C). In the next experiments, effects of UV-B radiation on first leaves of cucumber plants and effects of environmental conditions on the sensitivity of plant to UV-B were examined. Effects of UV-B radiation on enzymic properties of glutathione reductase (GR), rate-limiting enzyme in metabolic pathway to detoxify hydrogen peroxide, were also examined. Outline of the results obtained are as follows.(1)Epidermis of pea leaves has flavono … More id-like substances, which have absorbance peaks at 260 and 320 ns and little absorbance in visible region. The content of these substances showed a parallelism with resistance to UV-B radiation.(2)UV-B irradiation caused the growth retardation of cotyledons and first leaves of cucumber seedlings and chlorosis on first leaves at 20ﾟC. But, the growth retardation could not be found on the irradiation at 25ﾟC, though chlorosis was observed.(3)high intensity of ultraviolet-A (UV-A) restored the retardation of growth of first leaves when it was given together with UV-B. But, chlorosis caused by UV-B was not restored by UV-A radiation.(4)UV-B radiation lowered the affinity of GR in cotyledons to substrates. It was clarified in the present work that the sensitivity of cucumber plants to UV-B was dependent on temperature and light condition at the time of UV-B radiation. Mechanism of plant damage caused by UV-B radiation, defense mechanism to UV-B and, in addition, effects of environmental conditions on biosynthesis of UV absorbing substances must be more investigated. Less

紫外线-B（UV-B）区域（280-320nm）的辐射会导致植物的生长迟缓和可见损伤，例如叶片表面的氯化。这些损害似乎在植物生长过程中的环境条件下控制。损害的程度被认为取决于植物叶表皮中紫外线（UV）吸收物质的含量差异。在本研究中，将紫外吸收物质的含量与这些植物对紫外线C（UV-C）的抗性进行了比较。在下一个实验中，检查了UV-B辐射对黄瓜植物第一叶的影响，以及环境条件对植物对UV-B的敏感性的影响。还检查了UV-B辐射对谷胱甘肽还原（GR）的酶特性的影响，在代谢途径中限速酶限制过氧化氢。所获得的结果的轮廓如下。（1）豌豆叶的表皮具有黄酮……更多类似ID的物质，它们的吸光度为260和320 ns，并且在可见区域的吸光度很小。这些物质的含量显示出对UV-B辐射的抗性的平行性。（2）UV-B辐射导致子叶的生长迟缓，以及在20°C上的第一叶的黄瓜幼苗和氯化量的第一叶。但是，尽管观察到氯化量，但在25°C的照射下仍找不到生长迟缓。（3）高强度紫外线A（UV-A）恢复了与UV-B一起给出的第一叶的生长的延迟。但是，UV-B辐射没有恢复由UV-B引起的氯化。（4）UV-B辐射降低了子叶中GR的亲和力与底物的亲和力。在目前的工作中，澄清了黄瓜植物对UV-B的敏感性依赖于UV-B辐射时的温度和光条件。必须更研究由UV-B辐射，防御机制引起的植物损伤机制，此外，还必须更研究环境条件对紫外线吸收物质的生物合成的影响。较少的