Sensitivity of wild-type and mutant Trichoderma harzianum strains to fungicides

Rodrigo Herrera, David Núñez, Natalia Romero, Ximena Besoain, Luz María Pérez, Jaime Montealegre


R. Herrera, D. Nuñez, N. Romero, X. Besoain, L. M. Pérez, and J. Montealegre. 2012. Sensitivity of wild-type and mutantTrichoderma harzianum strains to fungicides. Cien. Inv. Agr. 39(3): 569-576. The germination of conidia in wild-type (Th11, Th12 and Th650) and mutant (Th11A80.1, Th12A10.1 and Th650-NG7) strains of Trichoderma harzianum that were exposed to different commercial fungicides was studied. All wild-type and mutant Trichodermastrains were germinated in the presence of 1,700 mg L-1 of pencycuron. The wild-type strains Th12 and Th650 and the corresponding mutant strains Th12A10.1 and Th650-NG7 were sensitive to all concentrations of iprodione and metalaxil + mancozeb. The EC50 (Median Effective Concentration) values for the different fungicides were between 10-1 and 10-4 less than the concentrations recommended for field applications; one exception was Phyto‑fos on Th650‑NG7, where this ratio was 0.72. These results establish whether some of these fungicides can be used in combination with the biocontrol agents evaluated.


biocontrol, biocontrol agents, control of tomato root diseases, fungicides, fungicide tolerant Trichoderma, integrated management

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