Protocols for growing plant symbioses; rhizobia

Agrobacterium rhizogenes-mediated transformation of Pisum sativum L. roots as a tool for studying the mycorrhizal and root nodule symbioses

In this study, we demonstrated the successful transformation of two pea (Pisum sativum L.) cultivars using Agrobacterium rhizogenes, whereby transgenic roots in the resulting composite plants showed expression of the gene encoding the green fluorescent protein. Subsequent to infection with A. rhizogenes, approximately 70%–80% of pea seedlings developed transgenic hairy roots. We found out that the transgenic roots can be efficiently nodulated by Rhizobium leguminosarum bv. viciae and infected by the arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis. The morphology of nodules in the transgenic roots was found to be identical to that of nodules observed in wild-type roots, and we also observed the effective induction of markers typical of the symbiotic association with AM fungi. The convenient protocol for highly efficient A. rhizogenes-mediated transformation developed in this study would be a rapid and effective tool for investigating those genes involved in the development of the two types of symbioses found in pea plants.

Medicago truncatula: Genetic and Genomic Resources

Medicago truncatula was chosen by the legume community, along with Lotus japonicus, as a model plant to study legume biology. Since then, numerous resources and tools have been developed for M. truncatula. These include, for example, its genome sequence, core ecotype collections, transformation/regeneration methods, extensive mutant collections, and a gene expression atlas. This review aims to describe the different genetic and genomic tools and resources currently available for M. truncatula. We also describe how these resources were generated and provide all the information necessary to access these resources and use them from a practical point of view. © 2017 by John Wiley & Sons, Inc.