Project description:Many of the microorganisms that are normally present in the soil, actually inhabit the rhizosphere and interact with plants. Those plant–microorganisms interactions may be beneficial or harmful. Among the first are the arbuscular mycorrhizal fungi (AMF). These soil fungi have been reported to improve plant resistance/tolerance to pests and diseases. On the other hand, soilborne pathogens represent a threat to agriculture generating important yield losses, depending upon the pathogen and the crop. One example is the “Sudden Death Syndrome” (SDS), a severe disease in soybean (Glycine max (L.) Merr) caused by a complex of at least four species of Fusarium sp., among which Fusarium virguliforme and F. tuccumaniae are the most prevalent in Argentina. This study provides, under strict in vitro culture conditions, a global analysis of transcript modifications in mycorrhizal and non-mycorrhizal soybean root associated with F. virguliforme inoculation. Microarray results showed qualitative and quantitative changes in the expression of defense-related genes in mycorrhizal soybean, suggesting that AMF are good candidates for sustainable plant protection against F. virguliforme.
Project description:Macrophomina phaseolina, a soil borne pathogen with a wide host range, causes the charcoal rot in soybean (Glycine max (L.) Merr). In Argentina, soybean is the most important crop as far as sowing surface cultivation concerns, and for this reason it is important to assess integrated disease management strategies in order to minimize the incidence of this disease and the consequent loss of performance culture. Previous studies have demonstrated the protective effect that arbuscular mycorrhizal can promote on their hosts against various pathogens invasion, especially against soil borne fungi. Therefore, the goal of this study was to analyze the phenomenon of mycorrhizae mediated protection by characterizing transcriptional changes using cDNA microarrays as a tool. The objective of the present study was to investigate, under strict in vitro culture conditions, the global transcriptional change in the roots of pre-mycorrhized soybean plantlets challenged by M. phaseolina as compared to non-mycorrhizal soybean plantlets. The MapMan software was used to distinguish transcriptional change under these conditions, with special emphasis on plant defence response.
Project description:Most land plants form beneficial associations with arbuscular mycorrhizal (AM) fungi which improves mineral nutrition, mainly phosphorus and nitrogen in the host plant in exchange for photosynthetically fixed carbon. Most of our knowledge on the AM symbiosis derives from dicotyledonous species. We show that inoculation with the AM fungus Funneliformis mossease stimulates growth and increases Pi content in leaves of the rice cultivar Loto (O. sativa ssp japonica). Although rice is a host for AM fungi, the molecular mechanism underlying the AM symbiosis, in particular the systemic transcriptional responses of shoots to AM inoculation, remain largely elusive. Transcript profiling of the shoots indicated the systemic induction of genes involved in the biosynthesis of phospholipids (phosphoinositides, inositol polyphosphates) and down-regulation of non-phosphorus lipids (galactolipids, sulfolipids) in leaves of mycorrhizal rice. Regulation of phospholipid biosynthesis genes appears to be coordinated with a reduced expression of genes involved in jasmonic acid and ethylene biosynthesis and signaling. Genes involved in phosphate starvation responses and remobilization of Pi were also found to be down-regulated in leaves of mycorrhizal rice. These results demonstrated that the AM symbiosis is accompanied by complex alterations in gene expression in shoots which are potentially important to maintain a stable symbiotic relationship in rice plants.
Project description:Analysis of cell specific gene expression in mycorrhizal rice roots. Described in Roth, Chiapello et al. 2019 We used LCM to harvest arbusculated and adjacent systemic cells from mycorrhizal rice roots, along with cortical cells from mock inoculated plants