Microorganisms of genus Trichoderma as phytohormone promoters and pathogen suppressors/ MICROORGANISMOS DEL GENERO Trichoderma PRODUCTORES DE FITOHORMONAS Y ANTAGONISTAS DE FITOPATOGENOS

• Published in: Bioagro Vol. 34; no. 2; p. 163
• Main Authors: Lopez-Valenzuela, Blanca E, Tzintzun-Camacho, Olivia, Armenta-Bojorquez, Adolfo D, Valenzuela-Escoboza, Fernando A, Lizarraga-Sanchez, Glenda J, Ruelas-Islas, Jesus del R, Gonzalez-Mendoza, Daniel
• Format: Journal Article
• Language: Spanish
• Published: Universidad Centroccidental Lisandro Alvarado 01.05.2022
• ISSN: 1316-3361
• DOI: 10.51372/bioagro342.6

Chemical products applied indiscriminately in agriculture have caused serious imbalances to the environment; thus, there is a need to use sustainable tools such as bioinoculants. Five strains of Trichoderma spp. were evaluated as producers of organic acids, auxins and gibberellins, as well as its antagonistic capacity and the radial growth inhibition percentage (RGIP) against the plant pathogens Fusarium oxysporum, Alternaria spp. and Helminthosporium spp. of Northern Mexico. Results showed that all strains segregated organic acids, with its maximum production attained at 72 hours. All of them synthetized auxins and gibberellins, with TF showing the highest production of auxins (35.3 [micro]g*[mL.sup.-1]), while no statistical differences among the strains were found for gibberellins. The highest value of RGIP against Fusarium oxysporum was found in TB (83.3%) and TJ3 (81.5%), while against Alternaria spp. the values ranged between 87.7% in TB and 86.7 in TM, without significant differences between them. The strain TJ3 got the highest value (76.6%) against Helminthosporium spp. The five strains showed class 1 and 2 of antagonistic capacity against the pathogens, showing a potential to be tested as biological control agents and plant growth promoters, a promising combination for a biotechnological product and sustainable tool in agricultural areas of Northern Mexico. Additional keywords: Alternaria, Fusarium, Helminthosporium, plant growth regulators Los productos quimicos aplicados indiscriminadamente en la agricultura, han causado graves desequilibrios al ambiente; por ello, la necesidad de utilizar alternativas sustentables como los bioinoculantes. Se evaluaron cinco cepas de Trichoderma spp. como productoras de acidos organicos, auxinas, giberelinas, asi como su efecto sobre el porcentaje de inhibicion del crecimiento radial (PICR) y su capacidad antagonica contra los fitopatogenos Fusarium oxysporum, Alternaria spp. y Helminthosporium spp. presentes en el noroeste mexicano. Los resultados mostraron que las cepas segregaron acidos organicos, y a las 72 horas se observo la maxima produccion. Todas las cepas sintetizaron auxinas y giberelinas, y entre ellas, TF presento la mayor produccion de auxinas (35,3 [micro]g*[mL.sup.-1]), mientras que para las giberelinas no se presentaron diferencias significativas entre las cepas. En el PICR, el mayor valor contra Fusarium oxysporum lo presentaron TB (83,3%) y TJ3 (81,5%), mientras que contra Alternaria spp., los valores variaron entre 87,7% para TB y 86,7% para TM, sin diferencias significativas entre ellos. Contra Helminthosporium spp., el mayor valor lo alcanzo TJ3 (76,6%). Las cepas exhibieron grados 1 y 2 de capacidad antagonica contra los fitopatogenos, demostrando su potencial para ser evaluadas como controladores biologicos e inductoras de crecimiento vegetal, combinacion promisoria como producto biotecnologico y alternativa sustentable para el sector agricola del noroeste de Mexico. Palabras clave adicionales: Alternaria, Fusarium, Helminthosporium, reguladores de crecimiento