Do soil microbes regulate citrus fruit quality through soil nutrient availability?

Area of Science:

• Agricultural Science
• Microbiology
• Soil Science

Background:

• The intricate relationship between soil microbiota and citrus fruit quality remains largely unexplored.
• Understanding these interactions is crucial for improving citrus production and quality.

Purpose of the Study:

• To investigate the influence of soil microbial communities on citrus fruit quality traits.
• To identify specific microbial taxa and soil properties associated with fruit characteristics like weight and Vitamin C content.

Main Methods:

• Collected citrus fruit and soil samples from fifteen orchards.
• Classified fruits into quality types (SL, SH, BH) using Principal Component Analysis (PCA).
• Analyzed microbial diversity (α, β-diversity), composition, and co-occurrence networks, alongside soil physicochemical properties.

Main Results:

• Significant differences in microbial abundances (Acidobacteriia, Deltaproteobacteria, Tremellomycetes) and fungal diversity (Shannon, Simpson indices) were observed across fruit quality groups.
• Fruit weight was correlated with soil pH, organic matter, nitrogen, and fungal diversity indices.
• Soil microbial taxa and phosphorus levels significantly influenced Vitamin C, titratable acidity, and soluble solids.

Conclusions:

• Soil microbial diversity, composition, and network structure collectively regulate soil nutrient availability.
• Soil nutrient availability, influenced by microbiota, is a primary determinant of citrus fruit quality.