Molecular identification and in vitro propagation of arbuscular mycorrhiza from tea plant rhizosphere

Abstract

The purpose of this research was to identify arbuscular mycorrhiza spores colonizing the rhizosphere of tea plants and attempt to propagate those spores in vitro. Soil samples from the tea plant rhizosphere were sieved, and arbuscular mycorrhizal spores were isolated and identified based on a morphological and molecular approach. Five species of arbuscular mycorrhiza were identified: Acaulospora mellea, Acaulospora spinosa, Glomus ambisporum, Glomus multicaule, and Scutellospora cerradensis. Eleven arbuscular mycorrhizal sequences were obtained, the phylogenetic analysis grouped the 11 sequences into five clades, belonging to the Acaulosporaceae, Gigasporaceae, and Glomeraceae genera. Among the five species identified in this study, only two were able to germinate during co-cultivation with an Arabidopsis root organ culture host. Scutellospora cerradensis and Glomus clarum germinated after three and seven days of incubation, respectively. However, the germ tube did not develop any further and was thus unable to infect the Arabidopsis root. Nevertheless, these results provided an overview of arbuscular mycorrhizal fungal species colonizing the tea rhizosphere as well as challenges for arbuscular mycorrhiza in vitro propagation using Arabidopsis root culture.