# Impacts of Soil Properties and Microbial Community on Fruit Quality and Yield in Ponkan Orchards with Different Comprehensive Performance

## TL;DR

This study explores how soil properties and microbes affect fruit quality and yield in citrus orchards, finding that better soil health and microbial diversity lead to improved outcomes.

## Contribution

The study integrates soil, microbial, and plant factors to identify key indicators for high-performance citrus orchards.

## Key findings

- Higher-performing orchards had better soil pH, organic matter, nutrients, and enzyme activities.
- Soil microbial diversity and Proteobacteria abundance were positively linked to fruit quality and yield.
- Leaf photosynthetic indexes were significantly higher in high-performing orchards.

## Abstract

Fruit quality and yield of citrus orchards are co-regulated by complex interactions among soil properties, microbial communities, and plant physiological processes. However, systematic studies that integrate the soil–microbe–plant–fruit continuum remain limited. This study selected four representative ponkan orchards based on yield and fruit quality performance, and systematically determined and correlated key indicators in the soil–plant–fruit continuum. The results showed that the orchards with higher comprehensive performance exhibited more suitable soil pH, higher contents of soil organic matter and available nutrients, as well as higher activities of soil enzymes including urease and acid phosphatase. Compared with the orchards with lower comprehensive performance, soil bacterial and fungal Chao1, Shannon, and Simpson indices were higher in the orchards with higher comprehensive performance. Among the dominant phyla, the relative abundance of Proteobacteria was significantly higher, while that of Actinobacteria was significantly lower. Leaf photosynthetic indexes (chlorophyll content, net photosynthetic rate, Rubisco activity) of the higher-performing orchards were also significantly higher. Correlation analysis showed that soil microbial diversity and Proteobacteria were significantly positively correlated with soil nutrients, enzyme activities, leaf photosynthesis, fruit quality and yield, while Actinobacteria showed the opposite trend. These results provide a theoretical basis for soil management and high-quality cultivation of ponkan orchards.