Snyder F W
Agriculture Research Service, United States Department of Agriculture, Michigan State University, East Lansing, Michigan 48823.
Plant Physiol. 1974 Mar;53(3):514-5. doi: 10.1104/pp.53.3.514.
Amount and products of photosynthesis during 10 minutes were measured at different (14)CO(2) concentrations in air. With tobacco (Nicotiana tabacum L. cv. Maryland Mammoth) leaves the percentage of (14)C in glycine plus serine was highest (42%) at 0.005% CO(2), and decreased with increasing CO(2) concentration to 7% of the total at 1% CO(2) in air. However, above 0.03% CO(2) the total amount of (14)C incorporated into the glycine and serine pool was about constant. At 0.005% or 0.03% CO(2) the percentage and amount of (14)C in sucrose was small but increased greatly at higher CO(2) levels as sucrose accumulated as an end product. Relatively similar data were obtained with sugar beet (Beta vulgaris L. cv. US H20) leaves. The results suggest that photorespiration at high CO(2) concentration is not inhibited but that CO(2) loss from it becomes less significant.
在空气中不同浓度的(14)CO₂条件下,测定了10分钟内光合作用的量和产物。对于烟草(Nicotiana tabacum L. cv. Maryland Mammoth)叶片,在CO₂浓度为0.005%时,甘氨酸和丝氨酸中(14)C的百分比最高(42%),随着CO₂浓度增加至空气中1%,该百分比降至总量的7%。然而,在CO₂浓度高于0.03%时,掺入甘氨酸和丝氨酸库中的(14)C总量大致恒定。在CO₂浓度为0.005%或0.03%时,蔗糖中(14)C的百分比和量较小,但随着蔗糖作为最终产物积累,在较高CO₂水平下大幅增加。用甜菜(Beta vulgaris L. cv. US H20)叶片获得了相对相似的数据。结果表明,高CO₂浓度下的光呼吸并未受到抑制,但其CO₂损失变得不那么显著。