Far-red light modulates grapevine growth by increasing leaf photosynthesis efficiency and triggering organ-specific...

Area of Science:

• Plant Physiology
• Molecular Biology
• Agricultural Science

Background:

• Far-red light, combined with shorter wavelengths, enhances photosynthesis in many plants.
• The impact of far-red light on sink organs and source-sink relationships in grapes remains largely unexplored.

Purpose of the Study:

• Investigate the effects of far-red light supplementation on grapevine growth and carbon allocation.
• Elucidate the underlying physiological and molecular mechanisms of far-red light action in grapes.

Main Methods:

• Grape plantlets were grown under natural light supplemented with either white or far-red light at equal intensities.
• Physiological measurements (photosynthesis rate, growth parameters) and transcriptomic analysis were conducted.
• Gene expression related to light signaling and carbon metabolism was analyzed.

Main Results:

• Far-red light increased stem length and carbohydrate content but reduced leaf area and weight.
• Net photosynthetic rate increased by 31.72% under far-red light, indicating enhanced efficiency.
• Transcriptome analysis revealed differential gene expression in leaves and sink organs, with key genes in light signaling and carbon transport upregulated.

Conclusions:

• Far-red light synergizes with white light to improve grape photosystem activity.
• Far-red light differentially influences the growth of sink organs in grapevines.
• Findings support the potential inclusion of far-red light within photosynthetically active radiation (PAR).