Nodulation of annual medicago by strains ofR. Meliloti in a commercial inoculant as influenced by soil phosphorus and pH


Four species of annual medics showed poor growth and little or no nodulation in an inoculated, acid soil low in available phosphorus. Nodulation was significantly increased by adding phosphorus to the soil. The number of nodules found on the roots of each species was approximately the same for soil at pH 5.5 or 6.8.

A commercial inoculant ofRhizobium meliloti was adequate for nodulation of all four species and two strains of rhizobia predominated in the nodules which were assayed by immunodiffusion.

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Wagner, G.H., Kassim, G.M. & Martyniuk, S. Nodulation of annual medicago by strains ofR. Meliloti in a commercial inoculant as influenced by soil phosphorus and pH. Plant Soil 50, 81–89 (1978).

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  • Nodule
  • Phosphorus
  • Plant Physiology
  • Rhizobium
  • Acid Soil