The combination of Arachis pintoi green manure and natural phosphate improves maize growth, soil microbial community structure and enzymatic activities

Aims We investigated the effect of the co-composting of Arachis pintoi (AP) as green manure with different sources of rock phosphate on maize growth and soil properties. Methods Composts were prepared combining AP and different rock phosphates (simple superphosphate, apatite rock phosphate, reactive rock phosphate and thermophosphate), alone or in combination with AP. The incorporation of AP and natural phosphate was conducted in a greenhouse, and we investigated its effects on plant total dry matter, phosphorus absorption, microbial biomass carbon and phosphorus, total organic carbon, soil basal respiration, enzymatic activities (acid phosphatase, alkaline phosphatase and urease) and the soil microbial structure community. Results The application of natural thermophosphate phosphates with AP is an efficient management strategy for maize cultivation, with increases of more than 124% in maize dry matter, more than 300% in P uptake and 62% in soil microbial biomass carbon. Conclusions The use of Arachis pintoi as green manure, combined with natural phosphate sources, represents an alternative fertilisation approach for maize cultivated on Entisols, enhancing the bioavailability of P from natural rock phosphate. It is a sustainable and financially attractive option to ensure the environmental integrity of cultivation, food and soil security.