NODULATION OF OILSEED RAPE (BRASSICA-NAPUS) BY RHIZOBIA

Nodules were induced on the non-legume oilseed rape, following enzyme treatment of seedling roots and inoculation with Rhizobium leguminosarum, Bradyrhizobium 32H1 or a mixture of R. loti with Bradyrhizobium 32H1 in the presence of PEG. A Nod+ strain of R. leguminosarum also induced nodules, but a Nod- strain failed to elicit this response. Nodules induced on oilseed rape were morphologically similar, when examined by light microscopy and cryo-scanning electron microscopy, to those induced on roots of white clover by R. trifolii. Transmission electron microscopy showed rhizobia within cells of the nodules. These observations are discussed with respect to the extension of Rhizobium symbiosis to non-legumes.