6533b85cfe1ef96bd12bc008

RESEARCH PRODUCT

Changes in the physiological and agricultural characteristics of peat-based Bradyrhizobium japonicum inoculants after long-term storage

Georges SommerJean-jacques GiraudG. MeunierCécile RevellinGérard CatrouxP. Wadoux

subject

0106 biological sciencesTime FactorsField experimentMicroorganismColony Count MicrobialBiologyRhizobacteria01 natural sciencesApplied Microbiology and Biotechnology03 medical and health sciencesYeast extractBradyrhizobiumDesiccation[SDV.MP] Life Sciences [q-bio]/Microbiology and ParasitologyMicrobial inoculantSoil Microbiology2. Zero hunger0303 health sciences030306 microbiologyCrop yieldfood and beveragesSoil classificationGeneral Medicinebiology.organism_classificationHorticulture[SDV.MP]Life Sciences [q-bio]/Microbiology and ParasitologyAgronomySoybeans010606 plant biology & botanyBiotechnologyBradyrhizobium japonicum

description

International audience; Commercial soybean inoculants processed with sterilised peat and stored at 20 °C for 1–8 years were used as experimental materials to assess the changes in the physiological activity of Bradyrhizobium japonicum after storage. Viable counts decreased and physiological characteristics of the bacterium changed during storage, with an increase in the time taken for colony appearance on a medium without yeast extract, an increase in the lag time for nodule appearance on soybean grown in glass tubes and a decrease in survival on seeds. All the inoculants produced a significant increase in grain yield in a field experiment. The percentage of efficient cells in the field (relative to the plate counts) decreased as the length of storage increased. These results suggest that the physiological activity of B. japonicum cells changes after storage. Practical implications for inoculant quality control are discussed.

https://doi.org/10.1007/s002530000373