在快速和慢速车道之间转换光合作用:选择性CAM和缺水压力
Klaus Winter1, Joseph A M Holtum2
1Smithsonian Tropical Research Institute, PO Box 0843-03092, Panama City, Panama.
Journal of plant physiology
|February 19, 2024
概括
植物可以在C3和Crassulacean酸代谢 (CAM) 光合作用之间切换,以应对环境压力. 这个可选的CAM提供了一种灵活的干旱耐受性策略,有可能被转化为作物.
科学领域:
- 植物生理学 植物生理学
- 光合作用研究研究 光合作用研究
- 压力生物学 压力生物学
背景情况:
- 在 * Mesembryanthemum crystallinum * 中发现环境触发的酸代谢 (CAM) 引入了 fakultative CAM 的概念.
- 选择性CAM描述了CAM在应对压力的可逆诱导,将其与发育变化区分开来.
- 了解选择性CAM对于植物适应和农业应用至关重要.
研究的目的:
- 审查教学CAM的发展和当前的理解.
- 评估多年生物种中C3-CAM转移的可逆性.
- 突出工程选择性CAM对作物干旱耐受性的潜力.
主要方法:
- 评论历史和当前的文献在选修CAM.
- 在循环湿干条件下的Clusia pratensis*中可逆C3-CAM切换的实验证明.
- 对环境触发因素的分析和CAM转移的本体遗传独立性.
主要成果:
- 选择性CAM是一种专门的环境响应,不仅仅与植物发展有关.
- *Clusia pratensis*表现出重复的C3到CAM切换,以应对湿-干-湿周期.
- 在选择性CAM物种中证实了CAM的可逆性.
结论:
- 选择性CAM为植物提供了一种灵活的机制,以应对波动的环境条件,特别是干旱.
- 像Clusia pratensis这样的多年生物种能够反复切换光合作用途径的能力强调了它的适应意义.
- 在C3作物中引入工程学科CAM为提高农业对干旱的抵御能力提供了一个有希望的途径.
更多相关视频
相关概念视频
01:57Adaptations that Reduce Water Loss
25.6K
Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and other cellular processes, evolutionary pressures on plants in different environments have driven the acquisition of adaptations that reduce water loss.
25.6K
01:27C4 Pathway and CAM
45.5K
Most plants use the C3 pathway for carbon fixation. However, some plants, such as sugar cane, corn, and cacti that grow in hot conditions, use alternative pathways to fix carbon and conserve energy loss due to photorespiration. Photorespiration is the process that occurs when the oxygen concentration is high. Under such conditions, the rubisco enzyme in the Calvin cycle binds O2 instead of CO2, which halts photosynthesis and consumes energy.
C4 Pathway
The C4 pathway is used by plants such as...
C4 Pathway
The C4 pathway is used by plants such as...
45.5K
01:46The Calvin Benson Cycle
4.5K
Ribulose 1,5- bisphosphate carboxylase/oxygenase (RuBisCo) is a critical enzyme that catalyzes carbon dioxide assimilation during photosynthesis. However, it is an inefficient enzyme, having an extremely slow catalytic rate. A typical enzyme can process about a thousand molecules per second; however, RuBisCo fixes only around three-carbon dioxides per second. Photosynthetic cells compensate for this slow rate by synthesizing very high amounts of RuBisCo, making it the most abundant single...
4.5K
02:41Responses to Drought and Flooding
10.7K
Water plays a significant role in the life cycle of plants. However, insufficient or excess of water can be detrimental and pose a serious threat to plants.
10.7K
02:02Responses to Salt Stress
13.1K
Salt stress—which can be triggered by high salt concentrations in a plant’s environment—can significantly affect plant growth and crop production by influencing photosynthesis and the absorption of water and nutrients.
13.1K
02:04Regulation of Transpiration by Stomata
28.3K
During photosynthesis, plants acquire the necessary carbon dioxide and release the produced oxygen back into the atmosphere. Openings in the epidermis of plant leaves is the site of this exchange of gasses. A single opening is called a stoma—derived from the Greek word for “mouth.” Stomata open and close in response to a variety of environmental cues.
28.3K