Jornal de Ciências Agrícolas e Pesquisa de Alimentos
Acesso livre

Abstrato

Isolation of Trichoderma Spp. from Desert Soil, Biocontrol Potential Evaluation and Liquid Culture Production of Conidia Using Agricultural Fertilizers

Montoya-Gonzalez AH, Quijano-Vicente G, Morales-Maza A, Ortiz-Uribe N and Hernandez-Martinez R

Three Trichoderma isolates were obtained from sandy soils collected at the “Gran Desierto de Altar” in the northwest of Mexico and characterized by morphologic and molecular analyses as Trichoderma harzianum 8.4, Trichoderma asperellum 12-2 and Trichoderma asperellum BP60. Isolate T. asperellum BP60 inhibited Setophoma terrestris, grew above 50°C, and produced chitinases and siderophores, therefore it was chosen to obtain enough biomass and conidia for field applications. Conidia production was intended in liquid culture fermentation using food grade ingredients and agricultural fertilizers. Assays were done using baffled Erlenmeyer flasks containing 75 mL of culture media, kept under constant agitation at 150 RPM, with initial pH adjusted to 6.5 (NaOH 1N) at 28 ± 2°C and evaluated at 3, 6, 9 and 12 days after inoculation (DAI). Among the carbon sources, sucrose and vinaze; the former induced higher yields of biomass and conidia. Regarding nitrogen sources, the fertilizer (NH4) NO3 induced higher conidia yield. V8 juice (V8) induced the highest effect on production of both biomass and conidia. Therefore, maximum yield was 1.06 × 109 conidia.mL-1, with the formulation with 5 g of KH2PO4 (MKP, Greenhow®), 1.3 g of MgSO4•7H2O (Sul-Mag, Peñoles®), 20 mg of FeCl3•6H2O (Fermont®), 150 ml of V8, 10 ml of vinaze and 2.5 g.L-1 of (NH4)NO3. Results presented here prove the potential for using an alternative, low cost, liquid media to produce conidia of T. asperellum.