Sorbitol promotes the graft healing process in pears

Area of Science:

• Plant Science
• Agricultural Science
• Biochemistry

Background:

• Pear propagation relies heavily on asexual reproduction through grafting.
• The metabolic exchange during graft union healing is crucial but not fully understood, especially regarding sugar metabolism.

Purpose of the Study:

• To systematically investigate the role of sugar metabolism in pear graft union healing using multi-omics approaches.
• To identify specific sugar metabolites and their associated genes influencing the healing process.

Main Methods:

• Comparative analysis of homografts and heterografts using micrografting techniques.
• Application of metabolomics and transcriptomics to analyze metabolic and gene expression changes.
• Spatial metabolomics to pinpoint metabolite localization and exogenous sorbitol treatment for functional verification.

Main Results:

• Significant differences in sugar metabolism pathways, particularly fructose and mannose, were observed between homografts and heterografts.
• Sorbitol levels showed opposite trends in homografts versus heterografts, linked to differential gene expression of metabolic enzymes.
• Spatial metabolomics confirmed sorbitol accumulation in the scion of homografts.
• Exogenous sorbitol application enhanced tissue adhesion, accelerated callus growth, and promoted xylem and phloem differentiation.

Conclusions:

• Sorbitol plays a critical positive role in promoting pear graft union healing.
• Understanding sugar metabolism, specifically sorbitol's function, can optimize grafting techniques for improved plant propagation.