Rhizobium japonicum Serogroup and Hydrogenase Phenotype Distribution in 12 States

H H Keyser1, D F Weber, S L Uratsu

  • 1Nitrogen Fixation and Soybean Genetics Laboratory, U.S. Department of Agriculture Agricultural Research Service, Beltsville, Maryland 20705, and Plant Growth Laboratory and Department of Agronomy and Range Sciences, University of California, Davis, California 95616.

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