Abstract
A bradyrhizobial-fungal biofilm (i.e. Bradyrhizobium elkanii SEMIA 5019-Penicillium spp.) developed in vitro was assayed for its nitrogenase activity and was evaluated for N2-fixing symbiosis with soybean under greenhouse conditions. The biofilm showed nitrogenase activity, but the bradyrhizobial strain alone did not. Shoot and root growth, nodulation and N accumulation of soybean increased significantly with an inoculum developed from the biofilm. This study concludes that such biofilmed inoculants can improve N2-fixing symbiosis in legumes, and can also directly contribute to soil N fertility in the long term. Further studies should be conducted to investigate the performance of these inoculants under field conditions.
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Acknowledgements
Microbiological studies in the project were initiated during the Sri Lankan-Belgian collaboration on biological N2 fixation (1991–1997). Resources generated through funding of Belgian Administration for Development Corporation (BADC) during that period were partially used in the present study. All members of the BNF project are acknowledged for their support during this study.
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Jayasinghearachchi, H.S., Seneviratne, G. A bradyrhizobial-Penicillium spp. biofilm with nitrogenase activity improves N2 fixing symbiosis of soybean. Biol Fertil Soils 40, 432–434 (2004). https://doi.org/10.1007/s00374-004-0796-5
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DOI: https://doi.org/10.1007/s00374-004-0796-5