Physiological and ecological mechanisms of response and adaptation of horticultural plant resources to compound environmental stress

在各种严重的环境胁迫下，研究了园艺植物资源对UV-B辐射和盐胁迫的响应和适应机制.通过改变UV-B的照射时间、强度、波长范围等不同的照射条件，研究了UV-B对5种蔬菜植物的生理生态响应，当UV-B到达植物表面后，将其分为短波长和长波长两个区域，300 nm及以下的紫外线与可见光的增减无关，且几乎呈固定量。对于卷心菜、菠菜、番茄、茄子和萝卜，在黑暗期或光照期照射UV-B，并将结果与对照进行比较。黑暗期高强度的UV-B使供试蔬菜叶片表面呈青铜色，叶缘向内卷曲， ...更多信息 ongland.可见光显示出减轻UV-B辐射损伤的效果。番茄对UV-B的敏感性最强，280 ~ 290 nm的UV-B对蔬菜的影响最大。经UV-B辐射处理的叶片柔韧性下降，含水量下降。对生长的影响在年轻的leg中观察到很强.通过对能在高盐环境下生长的紫菀（Aster tripolium L.）营养生长期的生理反应（生长、离子吸收和水分生理）及光合作用的研究，探讨了紫菀的耐盐机理，结果表明：水分胁迫和300 mM NaCl胁迫均使紫菀的生长受到抑制，且水分胁迫的抑制程度大于NaCl胁迫。叶片对Na^+和Cl^+的吸收量在NaCl胁迫下高于水分胁迫下，Na+/K+比值也高于水分胁迫下。在大气CO_2浓度为350 ppm的条件下，对照、水分胁迫和盐胁迫下的气孔限制率分别为对照的33%、52%和44%，无气孔限制的情况下，水分胁迫降低了光饱和光合速率，而NaCl胁迫则没有。NaCl胁迫下气孔部分关闭，限制了CO_2的供应，导致光合速率下降。光合作用的光、暗反应系统在NaCl胁迫下受到保护。同时，水分胁迫下气孔关闭，暗反应系统能力下降，光合速率降低。少

In various serious environmental stresses, we investigated mechanism of response and adaptation of the horticultural plant resources to ultraviolet-B radiation and salt stresses.1. By changing the various irradiation conditions such as exposure time, strength, and wavdength regions of UV-B, what kind of failure was generant to the plant by the UV-B irradiation, the physiological and ecological responses of five vegetable plant species to UV stress were investigated.When UV-B, which reaches the surface, was divided into shorter wavelength and longer wavelength regions than 300 nm, UV of 300nm or less was not related to increase and decrease of visible light, and it showed the almost fixed quantity.For cabbage, spinach, tomato, eggplant, and radish, UV-B was irradiated in the dark period, or light period, and the results was compared with the control. High-intense UV-B in the dark period made the surface of tested vegetable leaves into the bronze, and the leaf margin curled inside, and c … More ontracted. Visible light showed the effect that eases the damage by the UV-B irradiation. Tomato had the most UV-B sensitivity 280〜290nm of UV-B gave very intensive negative effects to the vegetables tested. Leaves that UV-B was irradiated had lacked the flexibility, and also decreased on the water content. The effect on the growth was strongly observed in younger leaves.2. Physiological response (growth, absorption of ions and water physiology) and photosynthesis in the vegetative growth stage of Aster tripolium L.Which was able to grow under the hyper saline environment, were investigated in order to clarify the salt tolerance mechanism.The growth lowered by water stress, and NaCl stress (300mM), and it decreased more in water stress than NaCl stress. Absorption of Na^+ and Cl^+ ino the leaves was higher in the NaCl stress than water stress, and the Na+/K+ ratio was also higher Water potential of the leaves in control, water stress, and NaCl stress lowered in order. Turgor pressure was almost same in control and NaCl stress, and lowered in water stress.Under the atmosphere CO_2 condition (350 ppm) the rates of stomatal limiting of photosynthesis in control, water stress, and salt stress were 33%, 52% and 44% of control respectively Without the stomatal limiting the light saturation photosynthetic rate was decreased in the water stress, but not in the NaCl stress. The photosynthetic rate was decreased because of limiting the supply of CO_2 through the partial closure of the stoma under NaCl stress. Light and dark reaction systems of photosynthesis, however, were protected in NaCl stress. In the meantime, the photosynthetic rate in water stress was lowered by closure of the stoma and decrease in the ability of the dark reaction system. Less