Biocontrol of Alternaria alternata and Fusarium oxysporum by Trichoderma asperelloides and Bacillus paralicheniformis in tomato plants

Authors: RAMIREZ-CARIÑO, HERIBERTO - Mixteca Technological University; GUADARRAMA-MENDOZA, PAULA - Mixteca Technological University; SANCHEZ-LÓPEZ, VLADIMIR - Upaep La Universidad Transformadora; CUERVO-PARRA, JAIME - Universidad Autonoma Del Estado De Hidalgo; RAMÍREZ-REYES, THALÍA - Mixteca Technological University; Dunlap, Christopher; VALADEZ-BLANCO, ROGELIO - Mixteca Technological University

Submitted to: Antonie Van Leeuwenhoek
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/2/2020
Publication Date: 6/20/2020
Citation: Ramirez-Cariño, H.F., Guadarrama-Mendoza, P.C., Sanchez-López, V., Cuervo-Parra, J.A., Ramírez-Reyes, T., Dunlap, C.A., Valadez-Blanco, R. 2020. Biocontrol of Alternaria alternata and Fusarium oxysporum by Trichoderma asperelloides and Bacillus paralicheniformis in tomato plants. Antonie Van Leeuwenhoek. 113: 1247-1261. https://doi.org/10.1007/s10482-020-01433-2.
DOI: https://doi.org/10.1007/s10482-020-01433-2

Interpretive Summary: An ARS researcher from Peoria, IL collaborated with scientists from a University Oaxaca, Mexico to characterize two potential microbial biocontrol agents against common fungal plant pathogens of tomato. These strains were assayed individually and together in greenhouse assays. Greenhouse trials with tomato plants showed the strains possessed the ability to control vascular wilt and early blight. Combinations of the two potential microbial biocontrol agents showed the same activity as the individual strains, with no synergism observed. This research benefits US farmer and consumers through the development of new crop protection strategies.

Technical Abstract: The objective of this work was to evaluate the effectiveness of the putative biocontrol agents (PBA) Bacillus paralicheniformis and Trichoderma asperelloides in vitro and in vivo to control two of the most important tomato plant diseases: vascular wilt (Fusarium oxysporum) and early blight (Alternaria alternata). The assessment of the in vitro interactions between the PBA and the phytopathogenic fungi was performed by dual confrontations assays. The biocontrol effectiveness of the individual and combined PBA treatments towards individual phytopathogen inoculations was evaluated in tomato plants. T. asperelloides was able to exert an outstanding mycoparasitic effect on both phytopathogenic fungi in the in vitro tests by hyphal strangulation and penetration. In addition, the individual PBA treatments were effective in the biocontrol of A. alternata and F. oxysporum in tomato plants reducing the plant disease severity in more than 53.8 and 66.7% for each of the pathogens, respectively. On the other hand, the combined use of the tested strains showed similar effectiveness in the biocontrol of A. alternata, but no synergism was observed. In addition, it was concluded that B. paralicheniformis protected the plants from the attack of A. alternata through the induction of the systemic resistance of the plant. This study demonstrated the effectiveness of the individual and combined use of the strains tested for the biocontrol of A. alternata and F. oxysporum in tomato plants.