Physiological and physicochemical controls on foliar volatile organic compound emissions

Area of Science:

• Biogeochemistry
• Plant Physiology
• Atmospheric Chemistry

Background:

• Plant leaves release diverse organic compounds involved in defense and tropospheric chemistry.
• Research has primarily focused on biochemical regulation of volatile emissions.
• Physicochemical properties also influence emission rates and patterns.

Purpose of the Study:

• To investigate the role of physicochemical factors in regulating plant volatile emissions.
• To understand how these factors interact with physiological limitations.
• To highlight the combined influence of physiological and physicochemical controls on emissions.

Main Methods:

• Analysis of volatile organic compound emission patterns.
• Investigation of leaf storage capacities for less volatile compounds.
• Modeling of diffusion processes through stomata.
• Assessment of emission responses to fluctuating environmental conditions.

Main Results:

• Physicochemical characteristics like low volatility and diffusion significantly control emission rates.
• Non-specific leaf storage buffers emissions against environmental fluctuations.
• Stomatal diffusion causes distinct emission bursts and alters diurnal patterns.
• Both physiological and physicochemical controls are critical in natural, fluctuating environments.

Conclusions:

• Physicochemical properties are as important as biochemical pathways in regulating plant volatile emissions.
• Understanding these dual controls is essential for predicting plant-atmosphere interactions.
• Emission regulation is a complex interplay of internal plant processes and external environmental factors.