Molecular Hydrogen Improves Blueberry Main Fruit Traits via Metabolic Reprogramming

Area of Science:

• Horticultural Science
• Plant Physiology
• Proteomics

Background:

• Improving fruit yield and quality is a key challenge for growers.
• Blueberry cultivation faces limitations in fruit size, taste, and shelf-life.

Purpose of the Study:

• To investigate the effects of hydrogen (H2)-based irrigation on blueberry (Vaccinium ashei 'Bluegem') fruit traits.
• To identify molecular mechanisms underlying H2-induced improvements in fruit yield and quality.

Main Methods:

• Hydrogen (H2)-based irrigation was applied to blueberry plants.
• Fruit traits, including weight, diameter, acidity, and sugar-acid ratios, were measured.
• Proteomic analysis using weighted protein co-expression network analysis (WPCNA) was performed.
• Metabolic pathways related to organic acids, fatty acids, and phenylpropanoids were analyzed.

Main Results:

• H2 irrigation significantly increased single fruit weight (14.59%) and equatorial diameter (4.19%).
• Fruit quality improved with decreased titratable acidity, increased solid-acid and sugar-acid ratios, higher total volatiles, vitamin C, and antioxidant capacity.
• Proteomic analysis implicated serine carboxypeptidase-like proteins (SCPLs), ADP ribosylation factors (ARFs), and UDP-glucosyltransferase (UGT85A) in H2-mediated growth.
• H2 regulated enzymes in sucrose metabolism, fatty acid degradation, and phenylpropanoid pathways, impacting organic acid, aroma, and anthocyanin levels.
• Upregulated heat shock proteins correlated with enhanced antioxidant activity.

Conclusions:

• Hydrogen irrigation offers a novel strategy for enhancing blueberry yield and fruit quality.
• Molecular insights reveal H2's role in regulating key metabolic and stress-response pathways.
• This approach holds promise for broader applications in horticultural crop improvement.