Arbuscular mycorrhiza on root-organ cultures

The study of arbuscular mycorrhizal (AM) fungi and the AM symbiosis formed with host plant roots is complicated by the biotrophic and hypogeous nature of the mycobionts involved. To overcome this, several attempts have been made during the last three decades to obtain this symbiosis in vitro. The use of root-organ cultures has proved particularly successful. In this review, we describe the method by which root-organ cultures (transformed and nontransformed) have been obtained, together with the choice of host species, inoculation techniques, and culture media. We also outline the potential use of continuous cultures and cryopreservation of in vitro produced spores for long-term germ plasm storage. Furthermore, this review highlights the considerable impact that in vitro root-organ cultures have had on studies of AM fungal morphology, taxonomy, and phylogeny and how they have improved our understanding of the processes leading to root colonization and development of the extraradical mycelium. This is supported by a summary of some of the most important findings, regarding this symbiosis, that have been made at the physiological, biochemical, and molecular levels. We also summarize results from studies between AM fungi and certain pathogenic and nonpathogenic soil microorganisms. We describe some of the limitations of this in vitro system and propose diverse avenues of AM research that can now be undertaken, including the potential use of a similar system for ectomycorrhizal research

Revue d'histoire du Bas-Saint-Laurent, vol. 17 (2)

Éditorial -- Les familles souches de Squatec -- La polyvalente de Squatec: vingt-cinq ans d'histoire 1969-1994 -- Matamajaw Salmon Club -- La pêche à l'anguille sur la Côte-du-Sud -- Saint-Narcisse-de-Rimouski, hier et aujourd'hui -- Quand les curés s'arrachaient les colons: le cas de l'abbé Antoine-Philippe Bérubé -- Le club Leblanc des Eaux Mortes -- Chroniques rimouskoises -- James-J. Jessop (1892-1939): avocat et maire de Rimouski -- Patrimoine: Une tournée historique: le patrimoine architectural de la région de Rivière-du-Loup -- Maison Hamel: la petite histoire d'une rimouskoise plus que centenaire -- La maison Gauvreau: une sauvegarde difficile -- Folklore: Naufrage du trois-mâts Amanda à Petit-Métis en 1841 -- On en fait toute une histoire au Musée du Bas-Saint-Laurent -- Paul Triquet, les 50 ans de sa croix Victoria -- En bref -- Des livres à lire