Isolation and characterization of Paenibacillus sp. SY6, a novel associative diazotroph with high nitrogenase activity from the white clover rhizosphere

In this study, we report the discovery of a novel Paenibacillus strain (SY6) exhibiting exceptionally high nitrogenase activity and moderate indole-3-acetic acid production, along with the capacity to colonize maize roots and significantly enhance nitrogen acquisition under nitrogen-limited conditions. These findings highlight both the mechanistic basis and agricultural potential of associative diazotrophs, providing a promising candidate for microbial biofertilizer development.