[en] This research focuses its interest in the olive tree because of its transcendent production and commercial value offered within the unconventional crops in Argentina. In the plantings of olive trees it was observed a drying syndrome, yellowing, defoliation, loss of vigor in roots, rot and death called drying of olive trees. In all the studied cases the pathogen P. palmivora was associated. In Argentina, in the last decades the increased incidence of this disease was observed and there is still no effective method of control. The objective was to study olive tree soils and to characterize cultivable bacteria constitutive of the microbiota of olive rhizosphere soil to find a method of efficient and agro-sustainable biological control. As a result, 452 bacteria from olive rhizosphere soil were obtained. Among these, there were 63 thermo-resistant bacteria one of which was characterized by its efficient antifungal activity, identified and deposited in GenBank under the access number KJ464036. This bacterium belonging to the Bacillus genus was able to control the development of the pathogen P. palmivora in 87.5 % in vitro and 84.8 % in vivo. The involved suppressive mechanism found so far was the production of ß-1.3-glucanase bacterial enzyme with mycolic activity. P. palmivora showed a deleterious effect on plants observed through a high percentage of symptomatic plants at 50 dpi, the presence of yellowing and drying in leaves and roots. In the presence of P. palmivora, the experimental bio-solution with 10 9 UFC.gss-1 exerted control over the fungus reflected in the absence of symptoms and a better plant growth. The beneficial action of Bacillus KJ464036 was influenced by the pathogen P. palmivora. The microorganism-plant interaction offers a promising and environmentally friendly strategy for conventional and organic agriculture worldwide.

[gl] Esta investigación centra o seu interese sobre a oliveira polo seu transcendente valor produtivo e comercial dentro dos cultivos non convencionais en Arxentina. En plantacións de oliveiras observáronse síndromes de desecado, amarelado, perda de follas e de vigor en raíces, podremia e morte que foron denominados seca de oliveiras. En todos os casos estudados achouse involucrado o patóxeno P. palmivora. En Arxentina, nas últimas décadas observouse o aumento da incidencia desta enfermidade e non existe aínda un método de control eficaz. O obxectivo foi estudar os chans de oliveirais e caracterizar bacterias cultivables constitutivas da microbiota do solo rizosférico de oliveira para atopar un método de control biolóxico eficiente e agrosustentable. Como resultados obtivéronse 452 bacterias a partir de solo rizosférico de oliveira. Entre estas acháronse 63 bacterias termorresistentes das cales una delas foi caracterizada pola súa eficiente actividade antifúnxica, identificada e depositada en GenBank baixo o número de acceso KJ464036. Esta bacteria pertencente ao xénero Bacillus foi capaz de controlar o desenvolvemento do patóxeno P. palmivora nun 87,5 % in vitro e nun 84,8 % in vivo. O mecanismo de supresividade involucrado atopado até o momento foi a produción da encima ß-1,3-glucanasa bacteriana con actividade micolítica. P. palmivora mostrou un efecto deletéreo sobre as plantas observado a través dunha elevada porcentaxe de plantas sintomáticas aos 50 d.p.i, presenza de amarelado e desecado en follas e raíz. En presenza de P. palmivora o bioformulado experimental con 109 UFC.gss-1 exerceu control sobre o fungo, o que tivo reflexo na ausencia de síntomas e nun mellor crecemento vexetal. A acción benéfica de Bacillus KJ464036 estivo influída polo patóxeno P. palmivora. A interacción microorganismo-planta ofrece unha estratexia prometedora e ambientalmente amigable para a agricultura convencional e orgánica en todo o mundo.