Title: | "The combination of two Bacillus strains suppresses Meloidogyne incognita and fungal pathogens, but does not enhance plant growth" |
Author(s): | Cruz-Magalhaes V; Guimaraes RA; da Silva JC; de Faria AF; Pedroso MP; Campos VP; Marbach PA; de Medeiros FH; De Souza JT; |
Address: | "Department of Phytopathology, Universidade Federal de Lavras, Lavras, Brazil. Department of Phytosanitary Defense, CCR, Universidade Federal de Santa Maria, Santa Maria, Brazil. Department of Chemistry, Universidade Federal de Lavras, Lavras, Brazil. Center for Agricultural, Biological and Environmental Sciences, Universidade Federal do Reconcavo da Bahia, Cruz das Almas, Brazil" |
ISSN/ISBN: | 1526-4998 (Electronic) 1526-498X (Linking) |
Abstract: | "BACKGROUND: The combination of biocontrol agents is a desirable strategy to improve control efficacy against the root-knot nematode (RKN) Meloidogyne incognita under field conditions. However, strains compatibility is generally tested in vitro and incompatible combinations are normally not further examined in experiments in planta. Therefore, there is virtually no information on the performance of incompatible strains. In this study, we evaluated two Bacillus strains previously described as incompatible in vitro for effects on plant growth and suppression of M. incognita, pathogenic fungi and nematophagous fungi. RESULTS: Strains BMH and INV were shown to be closely related to Bacillus velezensis. These strains, when applied individually, reduced the number of galls and eggs of M. incognita by more than 90% in tomato roots. When BMH and INV were combined (BMH + INV), RKN suppression and tomato shoot weight were lower compared to single-strain applications. Additionally, metabolites in cell-free supernatants and volatile organic compounds (VOCs) from strains BMH and INV had strong effects against the plant pathogens M. incognita, Fusarium oxysporum, Rhizoctonia solani and Sclerotium rolfsiii, but not against three species of nematophagous fungi. Although strain INV and the combination BMH + INV emitted fewer VOCs than strain BMH, they were still capable of killing second-stage juveniles of M. incognita. CONCLUSIONS: Bacillus strains BMH and INV inhibited M. incognita and fungal pathogens, and promoted tomato growth. However, strain INV emitted fewer VOCs and the combination BMH + INV did not enhance the activity of the biocontrol strains against the RKN or their capacity to promote plant growth. (c) 2021 Society of Chemical Industry" |
Keywords: | Animals *Ascomycota *Bacillus *Solanum lycopersicum Plant Roots *Tylenchoidea *Volatile Organic Compounds Bacillomycin biocontrol metabolites root-knot nematodes volatile organic compounds; |
Notes: | "MedlineCruz-Magalhaes, Valter Guimaraes, Rafaela A da Silva, Julio Cp de Faria, Amanda F Pedroso, Marcio P Campos, Vicente P Marbach, Phellippe As de Medeiros, Flavio Hv De Souza, Jorge T eng 409611/2018-2/CNPq - Brazil/ England 2021/10/25 Pest Manag Sci. 2022 Feb; 78(2):722-732. doi: 10.1002/ps.6685. Epub 2021 Nov 8" |