Browsing by Autor "Mayra Claros"

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Diversity of cultivable microorganisms associated with Quinoa (Chenopodium quinoa) and their potential for plant growth-promotion
(Universidad Católica de Oriente, 2022) José A. Castillo; Giovanna Conde; Mayra Claros; Noel Ortuño
Quinoa (Chenopodium quinoa) has grown since ancestral times in the Andean mountains and Altiplano, which are the center of origin of this pseudo-cereal. The interaction of Quinoa with native microorganisms may have contributed to the success of this plant in very adverse climatic and soil conditions. This study addressed the microbial diversity associated with Quinoa plants growing in traditional lands. We employed a cultivable-dependent approach to characterize the communities and identify bacterial strains with potential application in agriculture. We identified bacterial isolates belonging to phyla Firmicutes, Actinobacteria, Bacteroidetes, and Proteobacteria. The genera Bacillus and Rhizobium/Agrobacterium were the predominant groups in the Quinoa bacterial communities, while various Trichoderma species were also found in the fungi group. The plant growth-promoting ability of selected bacterial strains was assessed by culturing them on media and the in planta test. We used different assays to test the capabilities of the isolates for nitrogen fixation, phosphorus solubilization, and production of the phytohormone indole-3-acetic acid. We inoculated Quinoa seeds with some Bacillus strains and then evaluated plant growth and grain production. Plants inoculated with bacterial strains usually show increased growth parameters and grain yield. Altogether, this work reveals that Quinoa harbors many diverse cultivable bacteria and fungi, which could be used as biological amendments to promote plant growth in a chemical-free way. Avoiding chemical fertilizers helps reduce environmental pollution and maintains the organic character of Quinoa production. International Quinoa markets highly appreciate the organic quality of Quinoa. Keywords. Plant growth-promoting bacteria, Microbial diversity, Rhizosphere bacteria, Andean Altiplano, Trichoderma
Enhancing the Sustainability of Quinoa Production and Soil Resilience by Using Bioproducts Made with Native Microorganisms
(Multidisciplinary Digital Publishing Institute, 2013) Noel Ortuño; José A. Castillo; Mayra Claros; O. Navia; Marlene Angulo; Daniel Barja; Claudia Gutiérrez; Violeta C. Angulo
Microorganisms are involved in a network of interactions with plants, promoting growth and acting as biocontrol agents against diseases. In this work, we studied native microorganisms associated with quinoa plants (Chenopodium quinoa) and the application of these organisms to the organic production of quinoa in the Andean Altiplano. Quinoa is a non-cereal grain native to the Andean highlands and is highly nutritious and gluten-free. As such, the international demand for quinoa has increased substantially in recent years. We isolated native endophytic bacteria that are able to fix nitrogen, solubilize phosphate and synthesize a phytohormone and native strains of Trichoderma, a fungus typically used for increasing plant growth and tolerance to biotic and abiotic stresses. Greenhouse assays and field trials allowed for selecting promissory bacterial isolates, mostly belonging to Bacillus and Paenibacillus genera, that increased plant length, panicle weight and grain yield. Selected microbial isolates were large-scale multiplied in simple and inexpensive culture media and then formulated to obtain bioproducts that were distributed among local farmers. Thus, we developed a technology for the exploitation of beneficial microbes, offering promising and environmentally friendly strategies for the organic production of quinoa without perturbing the native microbial diversity of Andean soils and making them more resilient to the adverse effects of climatic change and the over-production of quinoa.
Selección de cepas de Trichoderma spp. generadoras de metabolitos secundarios de interés para su uso como promotor de crecimiento en plantas cultivadas
(Selva Andina Research Society, 2013) Noel Ortuño; Cláudia G. Miranda; Mayra Claros
secundarios de inters para
Selección de cepas de Trichoderma spp. generadoras de metabolitos secundarios de interés para su uso como promotor de crecimiento en plantas cultivadas
(Universidad Internacional de La Rioja, 2013) Ortuño Noel; Miranda Claudia; Mayra Claros
The Trichoderma Trichoderma interaction of 35 strains was studied becau\nse of the fungal potential to synthesize\nSecondary Metabolites (MS), such as the 3-indoleacetic acid (IAA), by using dual confrontations in solid crop of\npotato-dextrose-agar (PDA) as a selecting method for forming strains of "defense\nbarrier" between 0.5-0.7cm with an\noptimum width selection. 20\ndual confrontations were identified. These\nwere replicated in liquid culture potato-\ndextrose broth (PDB) under constant stirring. After 9 days\nof growth, the filtration was performed to separate the\nmetabolites synthesized by the fungus mycelium formed. Th\nis substance of interest, containing the MS, was\ninoculated into two crops:\nLactuca sativa\nand Raphanus sativus. \nIt was found that the best treatments for testing are the\nLactuca sativa 3(BP-T0001-BPT0029), 4(BP-T0006-BPT0028),7(BP-\nT0007-BPT0024) confrontations and the\nindividual crop I (BP- T0028) as the best inducer strain\ns of growth and involving weight, length , root volume and\nleaf weight . For testing of\nRaphanus sativus, the best treatments are the confrontation 10 (BP- T0015 - BPT0025)\nand the individual K crop (BP-T0031) as inducers of root\nlength, diameter and bulb\nweight. The individual G crop\n(BP-T0024) and the chemical fertilizer\nQUI, inducers of leaf weight and the confrontation 3(BP- T0001-BPT0029) as inducer of root weight. Therefore, the MS synthesized by\nTrichodermaspp. MS during dual confrontations act as Growth Promoters in Plants (PGP)
Symbiotic Native Microorganisms of Quinoa in the Bolivian Altiplano
(2021) Noel Ortuño; José A. Castillo; Mayra Claros
The use of secondary metabolites extracted from <i>Trichoderma</i> for plant growth promotion in the Andean highlands
(Cambridge University Press, 2016) Noel Ortuño; José A. Castillo; Miranda Claudia; Mayra Claros; Ximena Soto
Abstract Agriculture in the Altiplano and Andean Mountains is experiencing threats to sustainability mainly due to intensive cultivation of quinoa driven by international markets. This recent export-oriented production system is causing the degradation of soils and reducing productivity, therefore, agro-technological innovations are necessary to sustain cropping systems while maintaining organic quality (mostly quinoa). In this work, we searched for native Trichoderma species associated with plants from the Andean highlands to obtain an environmentally friendly and organic alternative to chemical fertilizers. We obtained different Trichoderma isolates from quinoa, potato and maize roots and soil, which were identified as Trichoderma harzianum , as well as other species. Twelve of the isolates were cultured in pairs to stimulate the production and secretion of compounds of diverse chemical nature that we called collectively ‘secondary metabolites’ (SMs). Crude extracts of SMs were used to inoculate selected crops to determine their plant growth promoting potential compared with two commercially available controls, chemical fertilizer and a bio-fertilizer. Results showed that SMs significantly promoted lettuce and radish growth and increased quinoa grain yield. Indole acetic acid was detected in all SM extracts that promoted plant growth, suggesting that this plant regulator might be responsible for the plant growth promoting activity. In conclusion, the Trichoderma -derived SMs approach appears to be a promising, simple and accessible technology for small-scale farmers in order to insure the sustainability, affordability and accessibility of food production in the Andes.