Project description:Rings or arcs of fungus-stimulated plant growth occur often on the floor of woodlands which are commonly called “fairy rings”. We purified a plant growth-stimulating compound, 2-azahypoxanthine (AHX), from the fairy ring-forming fungus Lepista sordida, and the detection of AHX in the fungus-infected soil near the growth-stimulated turfgrass roots. The growth-promoting activity of AHX towards rice was further analyzed by oligo DNA microarrays.
Project description:Piriformospora indica, an endophytic fungus of Sebacinales, colonizes the roots of many plant species including Arabidopsis thaliana. The symbiotic interaction promotes plant per-formance, growth and resistance/tolerance against abiotic and biotic stress. We demonstrate that exudated compounds from the fungus activate stress and defense responses in the Arabidopsis roots and shoots before the two partners are in physical contact. They induce stomata closure, stimulate reactive oxygen species (ROS) production, stress-related phytohormone accumulation and activate defense and stress genes in the roots and/or shoots. Once a physical contact is established, the stomata re-open, ROS and phytohormone levels decline, and the gene expression pattern indicates a shift from defense to mutualistic interaction. We propose that exudated compounds from P. indica induce stress and defense responses in the host. Root colonization results in the downregulation of defense responses and the activation of genes involved in promoting plant growth, metabolism and performance.
Project description:Possitive effects of plant growth promoting bacteria (PGPB) inoculation on plant growth and development are dependent on interaction between bacterial strains and plant roots, which are usually the bacterial niche. Furthermore, phytohormones are key regulators of plant physiology. Ethylene is essential in plant growth and development and in response to drought. Plant sensibility to ethylene is involved in plant response to PGPB strain inoculation and plant growth promotion. We used microarrays to detail the global programme of gene expression underlying plant interaction with two different PGPB strains (isolated from arid soils in southern Spain) regarding to plant sentitivity to ethylene by tomato ethylene receptor 3 (SlETR3).
Project description:Piriformospora indica, an endophytic fungus of Sebacinales, colonizes the roots of many plant species including Arabidopsis thaliana. The symbiotic interaction promotes plant per-formance, growth and resistance/tolerance against abiotic and biotic stress. We demonstrate that exudated compounds from the fungus activate stress and defense responses in the Arabidopsis roots and shoots before the two partners are in physical contact. They induce stomata closure, stimulate reactive oxygen species (ROS) production, stress-related phytohormone accumulation and activate defense and stress genes in the roots and/or shoots. Once a physical contact is established, the stomata re-open, ROS and phytohormone levels decline, and the gene expression pattern indicates a shift from defense to mutualistic interaction. We propose that exudated compounds from P. indica induce stress and defense responses in the host. Root colonization results in the downregulation of defense responses and the activation of genes involved in promoting plant growth, metabolism and performance. Twelve day-old (48 h cold treatment and 10 days of illumination) Arabidopsis seedlings of equal sizes were selected for co-cultivation experiments. They were transferred to PNM plates with a nylone membrane on the top (Johnson et al. 2011) and exposed to a fungal plug 5 mm in diameter or a KM plug of the same size without fungal hyphae (control). The plugs were placed 3 cm away from the closest root part . The light intensity (80 ± 5 μmol m-2 sec-1) was checked every third day to ensure that both P. indica- and mock-treated seedlings receive equal amounts of light.
Project description:Fairy rings are zones of stimulated grass growth by the interaction between the fungi and the plant. In the previous research, we reported the identification of the “fairy”, 2-azahypoxanthine (AHX), produced by the fairy ring-forming fungus and the mechanism of its growth-promoting activity using DNA microarray. We discovered AOH, a common metabolite of AHX in plants. We investigate expression profiling of rice seedlings treated with AHX or AOH for the mechanism of their growth-promoting activity.
Project description:Fairy rings are zones of stimulated grass growth by the interaction between the fungi and the plant. In the previous research, we reported the identification of the M-bM-^@M-^\fairyM-bM-^@M-^], 2-azahypoxanthine (AHX), produced by the fairy ring-forming fungus and the mechanism of its growth-promoting activity using DNA microarray. We discovered AOH, a common metabolite of AHX in plants. We investigate expression profiling of rice seedlings treated with AHX or AOH for the mechanism of their growth-promoting activity. Three-condition experiment, control vs. AHX-treated rice (50 and 200 mM) and AOH-treated rice (50 and 200 mM).