Comparative Transcriptome and Microscopy Analyses Provide Insights into Flat Shape Formation in Peach (Prunus...

Area of Science:

• Plant genetics
• Developmental biology
• Pomology

Background:

• Fruit shape is a key consumer trait, with flat peach cultivars gaining popularity.
• Understanding the cellular and genetic basis of flat fruit formation is crucial for breeding.

Purpose of the Study:

• To investigate the cellular and genetic mechanisms underlying flat fruit development in peaches.
• To compare cell number, cell size, and gene expression between flat and round peach cultivars.

Main Methods:

• Comparative analysis of cell division timing and fruit dimensions.
• RNA sequencing (RNA-seq) to identify differentially expressed genes (DEGs).
• Correlation analysis between cell number, vertical diameter, and fruit weight.

Main Results:

• Flat peaches exhibit significantly fewer cells along the vertical axis due to early cessation of cell division (15 days after full bloom vs. 35 days).
• A strong linear relationship exists between vertical cell number, fruit vertical diameter, and fruit weight.
• RNA-seq identified 4165 DEGs, with 28 candidate genes implicated in flat shape formation.

Conclusions:

• Peach fruit shape is primarily determined by the regulation of cell production along the vertical axis during early development.
• Identified candidate genes provide targets for marker-assisted breeding of flat peach varieties.