[Microbial metabolism in typical flooded paddy soils ].

Area of Science:

• Environmental microbiology
• Soil science
• Metagenomics

Background:

• Long-term fertilization impacts soil microbial communities and functions.
• Understanding microbial activity in paddy soils is crucial for agricultural sustainability.

Purpose of the Study:

• To investigate the composition and metabolic activities of active microorganisms in long-term fertilized (NPK) and unfertilized (CK) flooded paddy soils using environmental transcriptomics.

Main Methods:

• Soil microcosms were incubated, followed by total RNA extraction and transcriptome sequencing.
• Metagenomic analysis was performed using the MG-RAST server for taxonomic and functional classification.

Main Results:

• Bacteria constituted over 95% of transcripts, with Proteobacteria and Thaumarchaeota being dominant in both treatments.
• Transcriptional activity of Acidobacteria was significantly higher in NPK-treated soils.
• Microbial metabolism focused on energy production, carbohydrate, protein, and amino acid metabolism, with ABC transporters being the most highly expressed genes.

Conclusions:

• Microbial composition was largely similar between NPK and CK treatments, with notable differences in Acidobacteria activity.
• Dominant metabolic activities, including energy and protein metabolism, remained consistent across treatments.
• Long-term inorganic fertilization did not significantly alter the dominant microbial metabolic activities in these flooded paddy soils.