Arbuscular mycorrhizal fungal-induced alteration to root architecture in strawberry and induced resistance to the root pathogenPhytophthora fragariae

Abstract

Three strawberry cultivars Elsanta, Cambridge Favourite and Rhapsody were inoculated with either Glomus fasciculatum or GIomus etunicatum and their growth compared with non-inoculated plants. The roots of all inoculated plants were 55 to 70% colonised after 98 days. Increases in both root and shoot dry weights were measured. Root architecture was atso determined and increases in branching were evident in AMF colonised root systems. The remaining plants were then inoculated with the root pathogen Phytophthorafragariae and allowed to grow for a further 58 days before harvest. In two of the cultivars, Cambridge Favourite and Elsanta, AMF reduced root necrosis by approximately 60 and 30% respectively. Only in the least susceptible cultivar, Rhapsody, was no reduction measured in AMF colonised plants. There were differences in the control conferred by the two arbuscular mycorrhizal fungi and this suggests there may be practical benefits of inoculation. Relationships between the presence of roots of different orders, on inoculation with the pathogen, and subsequent necrosis provided a mechanism for identifying root-architecture driven alteration to susceptibility. Root system necrosis was positively correlated with the proportion of the root system made up of higher order roots (3 ° to 4 °) in non-colonised plants and negatively correlated in AMF colonised plants. These data suggest that root-architecture changes are not important per se but factors expressed concurrently may be.

The Influence of Bioproducts on Mycorrhizal Occurrence and Diversity in the Rhizosphere of Strawberry Plants under Controlled Conditions

“…Norman et al [65] observed that strawberry plants cv. "Elsanta", "Cambridge favourite" and "Rhapsody" inoculated with AMF increased root weight, and root colonisation, three months after inoculation.…”

Alterations in Root Morphology of Rootstock Peach Trees Caused by Mycorrhizal Fungi

“…The species G. fasciculatum and G. etunicatum induced modification in the roots of the Elsanta and Cambridge Favorite strawberry cultivars, but did not cause any alteration in the morphology of the roots of the Rhapsody cultivar, shedding the variable effect of these AMF species on different cultivars of the same plant species (Norman et al, 1996).…”

“…However, the relationships involved in the formation of this symbiosis, since the signaling between the phytobionts, the early stages of the colonization process, as well as possible alterations in the morphological structure of the roots (Berta et al, 1995), in order to be considered a complete understanding relations between the symbionts There is little information about such relationships, as well as morphological changes produced by mycorrhizal infection in plant tissues . Some authors report that the AMF does not cause major morphological changes in roots (Cooper, 1984), but studies showed that the AMF induces changes in the architecture (Berta et al, 1995;Norman et al, 1996), especially in the increase of the root ramification, in the morphology (Berta et al, 1995;Bressan & Vasconcelos, 2002;Kothari et al, 1990;Norman et al, 1996,) and the anatomy (Berta et al, 1995) the roots of different plant species.…”

Effect of an Endomycorrhizal Inoculum on the Growth of Argan Tree Plants

“…(Norman et al, 1996). Caravaca et al (2003) showed that the root mass of Dorycnium pentaphyllum plants inoculated with Glomus intraradices increased by 116% compared to that observed in non-mycorrhizal plants.…”