叶片发育过程中苹果的光合特性变化。

Changes in photosynthetic characteristics during leaf development in apple.

机构信息

Department of Horticulture and Landseape Architecture, Washington State University, 99164, Pullman, Washington, USA.

出版信息

Photosynth Res. 1981 Sep;2(3):213-23. doi: 10.1007/BF00032360.

Abstract

A comprehensive developmental survey of leaf area, chlorophyll, photosynthetic rate, leaf resistance, transpiration ratio, CO2 compensation point and photorespiration was conducted in apple. The largest changes in each of the photosynthetic characteristics studied took place during the earliest stages of leaf development, coinciding with the period of greatest leaf expansion and chlorophyll synthesis. During early development, photosynthesis increased 5-fold, reaching a maximum rate of 40 mg CO2 dm(-2) hr(-1) at a leaf plastochron index (LPI) of 10. During this same period, leaf resistance, transpiration ratio, CO2 compensation point and mesophyll resistance decreased, while carboxylation efficiency increased. Two especially interesting aspects of the data discussed are simultaneous changes that occur at a LPI of 10 and 12 in all of the photosynthetic characteristics examined and an apparent decrease in photorespiration as leaves age. From our results it is clear that stage of leaf development is an important factor affecting the rate of photosynthesis and photorespiration.

摘要

对苹果的叶面积、叶绿素、光合速率、叶片阻力、蒸腾比、CO2 补偿点和光呼吸进行了全面的发育调查。研究中每一种光合特性的最大变化都发生在叶片发育的最早阶段，与叶片扩展和叶绿素合成的最大时期相吻合。在早期发育过程中，光合作用增加了 5 倍，在叶龄指数（LPI）为 10 时达到 40mgCO2dm(-2)hr(-1)的最大速率。在同一时期，叶片阻力、蒸腾比、CO2 补偿点和叶肉阻力降低，而羧化效率增加。讨论数据的两个特别有趣的方面是，在所有检查的光合特性中，LPI 为 10 和 12 时同时发生的变化，以及叶片衰老时光呼吸明显减少。从我们的结果可以清楚地看出，叶片发育阶段是影响光合作用和光呼吸速率的一个重要因素。