在C3和C4草中,叶子深呼吸的变化与使用不同的基板有关
Yuzhen Fan1,2, Guillaume Tcherkez2,3, Andrew P Scafaro1,2
1ARC Centre of Excellence in Plant Energy Biology, Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia.
Plant physiology
|February 7, 2024
概括
在C3和C4草中,在中午和午夜之间,叶子深呼吸 (Rdark) 率和呼吸系数 (RQ) 显著变化. 植物呼吸中的这些日间差异受到各种代谢途径的影响,而不仅仅是碳水化合物使用.
科学领域:
- 植物生理学 植物生理学
- 生物化学 生物化学
- 代谢学 代谢学 代谢学
背景情况:
- 了解植物呼吸的日间变化对于准确建模光合作用和光呼吸至关重要.
- 以前的研究经常在单个时间点测量呼吸系统特性,忽略了昼夜周期的影响.
研究的目的:
- 为了研究C3和C4草中中午和午夜之间的叶子深呼吸 (Rdark) 和呼吸系数 (RQ) 的差异.
- 探索Rdark,RQ和叶子代谢组之间的关系.
主要方法:
- 在八种C3和C4草种中,在中午和午夜测量了叶子深呼吸 (Rdark) 的CO2和O2交换率.
- 呼吸系数 (RQ) 被计算为CO2释放与O2吸收的比率.
- 进行了叶片样本的代谢分析,以评估与Rdark和RQ的相关性.
主要成果:
- 叶子深呼吸 (Rdark) 在中午比午夜更高,特别是在C4草中.
- 在二氧化碳的基础上,Rdark的日间差异比在O2的基础上更明显.
- 呼吸系数 (RQ) 在所有物种中午通常高于午夜,但有显著的例外.
- 代谢分析显示Rdark/RQ与各种代谢物之间存在强烈的多变量关系,不仅仅是简单的碳水化合物.
结论:
- 叶子深呼吸 (Rdark) 和呼吸系数 (RQ) 在草中呈现显著的日间变化,受白天时间和物种类型 (C3/C4) 的影响.
- 这些变异是由多种代谢途径驱动的,包括三酸循环,酸途径,银河糖代谢和二次代谢,利用各种基质.
- 植物呼吸是一个动态的过程,取决于时间,物种和基质的可用性.
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