Mächler F, Nösberger J, Erismann K H
Institut für Pflanzenbau, Eidgenössische Technische Hochschule, Universitätsstr. 2, CH-8092, Zürich, Switzerland.
Pflanzenphysiologisches Institut der Universität Bern, Altenbergrain 21, CH-3013, Bern, Switzerland.
Oecologia. 1977 Jan;31(1):79-84. doi: 10.1007/BF00348711.
Two Trifolium repens clones from natural meadows at 600 m and 2030 m above sea level, and with differing dependence on temperature of their rate of apparent photosynthesis, were grown under controlled environments. Radioactive products in detached leaves were examined after 20 and 40 s periods of steady state photosynthesis in CO at 3° C and 24° C. Glycine and serine were hardly labeled at 3° C. At 24° C, the leaves of the alpine clone showed significantly, (P<0.025) more activity in these amino acids than those from the low altitude clone. It is suggested that the alpine clone has a higher photorespiration. This is supported by the labeling pattern of glucose, fructose, sucrose, and glucose-6-phosphate.The high altitude clone requires lower temperatures for photosynthesis than the low altitude clone. It is suggested, that this is caused by its higher photorespiration, which reduces net photosynthesis at high temperatures. The lower photorespiration activity of the low altitude clone can be interpreted as an adaptation to its warmer habitat.
从海拔600米和2030米的天然草甸中选取了两个白三叶草克隆体，它们的表观光合速率对温度的依赖程度不同，在可控环境下进行培养。在3℃和24℃的CO₂环境中，经过20秒和40秒的稳态光合作用后，对离体叶片中的放射性产物进行了检测。在3℃时，甘氨酸和丝氨酸几乎没有被标记。在24℃时，高山克隆体的叶片在这些氨基酸中的活性明显（P<0.025）高于低海拔克隆体的叶片。这表明高山克隆体具有较高的光呼吸作用。葡萄糖、果糖、蔗糖和葡萄糖-6-磷酸的标记模式支持了这一点。高海拔克隆体进行光合作用所需的温度低于低海拔克隆体。有人认为，这是由于其较高的光呼吸作用导致的，光呼吸作用在高温下会降低净光合作用。低海拔克隆体较低的光呼吸活性可以解释为对其较温暖栖息地的一种适应。
