Dose-optimized microbial inoculants reshape grape rhizosphere microbiota and enhance fruit quality

Area of Science:

• Agricultural Science
• Microbiology
• Soil Science

Background:

• Soil microbial communities are vital for plant growth, soil quality, and fruit yield.
• Understanding microbial inoculant effects is key to sustainable agriculture and crop improvement.

Purpose of the Study:

• To evaluate the impact of varying microbial inoculant doses on soil health, plant stress resistance, and grape quality.
• To identify optimal inoculant application rates for agricultural benefits.

Main Methods:

• Rhizosphere microbial communities were analyzed using high-throughput sequencing.
• Soil physicochemical properties, plant physiological parameters, and grape fruit quality were measured across five treatment groups (CK, 45, 90, 135, 180 L/ha).

Main Results:

• Inoculant application altered microbial community structure, increasing beneficial bacteria (Proteobacteria, Actinobacteria) and specific fungi (Mortierellomycota, Basidiomycota), while decreasing some fungi (Ascomycota).
• Significant improvements were observed in soil nutrient availability, enzyme activity, plant antioxidant capacity, and grape quality (soluble sugars, vitamin C) at 90 L/ha.
• Higher doses (135-180 L/ha) showed diminished effects and increased costs, indicating a dose-dependent response.

Conclusions:

• Compound microbial inoculants effectively modulate rhizosphere microbial communities.
• Optimized inoculant application enhances soil-plant system metrics, offering a sustainable approach to agriculture.