# The Molecular Mechanism and Effects of Root Pruning Treatment on Blueberry Tree Growth

## TL;DR

Root pruning promotes blueberry growth by enhancing above-ground biomass and activating key metabolic pathways, offering a strategy to improve plant yield.

## Contribution

This study reveals the molecular mechanisms linking root pruning to enhanced blueberry growth through transcriptomics and physiological analyses.

## Key findings

- Appropriate root pruning (CT4) significantly increased above-ground and leaf biomass within 42 days.
- Transcriptomics showed activation of cellulose and starch metabolism pathways and upregulation of vascular development transcription factors.
- Enhanced photosynthesis and vascular transport supported coordinated aboveground and belowground growth.

## Abstract

Root pruning can promote the transplanting of young green plants, but the overall impact of pruning on root growth, morphology, and physiological functions remains unclear. This study integrated transcriptomics and physiological analyses to elucidate the effects of root pruning on blueberry growth. Appropriate pruning (CT4) significantly promoted plant growth, with above-ground biomass and leaf biomass significantly increasing compared to the control group within 42 days. Photosynthesis temporarily decreased at 7 days but recovered at 21 and 42 days. Transcriptomics analysis showed that the cellulose metabolism pathway was rapidly activated and influenced multiple key genes in the starch metabolism pathway. Importantly, transcription factors associated with vascular development were also significantly increased at 7, 21, and 42 days after root pruning, indicating their role in regulating vascular differentiation. Enhanced aboveground growth was positively correlated with the expression of photosynthesis-related genes, and the transport of photosynthetic products via vascular tissues provided a carbon source for root development. Thus, root development is closely related to leaf photosynthesis, and changes in gene expression associated with vascular tissue development directly influence root development, ultimately ensuring coordinated growth between aboveground and belowground parts. These findings provide a theoretical basis for optimizing root pruning strategies to enhance blueberry growth and yield.