Interaction Between Different Amoebae and Pseudomonas sp. Impacts Rice Plant Growth and Phosphorus Dynamics

Area of Science:

• Soil microbiology
• Plant nutrition
• Ecosystem dynamics

Background:

• Microbial mineralization of soil phosphorus (P) is crucial for plant nutrition.
• The influence of interactions between phosphate-solubilizing bacteria and bacterivorous protists on P dynamics remains largely unexplored.

Purpose of the Study:

• To investigate the combined impact of phosphate-solubilizing Pseudomonas sp. and three amoebae species on soil and plant P dynamics.
• To assess the potential of these microbial interactions for enhancing plant growth and nutrient availability.

Main Methods:

• Experimental setup involving Pseudomonas sp. and three amoebae species (Vermamoeba vermiformis, Acanthamoeba lenticulata, Acanthamoeba genotype T4) in soil.
• Measurement of plant growth parameters, plant P uptake, alkaline phosphatase activity (APA), percentage of siderophore units (PSU), and soil available phosphorus (AP).

Main Results:

• Combined amoebae-Pseudomonas sp. treatments significantly enhanced plant growth compared to controls or Pseudomonas sp. alone.
• Specific combinations (A10Ps, A23Ps) showed greater plant P uptake and increased soil available phosphorus.
• Alkaline phosphatase activity and siderophore production were significantly higher in certain combined treatments.

Conclusions:

• Trophic interactions between Pseudomonas sp. and amoebae are vital for solubilizing phosphorus in soil.
• Developing combined Pseudomonas sp.-amoebae bioinoculants offers a promising strategy for enhancing nutrient mineralization, availability, and plant growth.
• Further research with broader screening is needed before field application.