Effective and Ineffective Strains of Legume Nodule Bacteria

PROF. A. I. VIRTANEN, in a recent article in Nature1, gave a brief summary of the work carried out in his laboratory on legume nodule bacteria. We await with interest the publication of these results in detailed form. It is already clear, however, that some of our investigations at Rothamsted have been on lines parallel to his, and that our results are complementary to some that he describes. A summary of our work where it touches on that at Helsinki may therefore be of interest.