Bioprospecting Fluorescent Pseudomonas from the Brazilian Amazon for the Biocontrol of Signal Grass Foliar Blight

Autor(es)

Vicentini, Samara Nunes Campos ; de Carvalho, Giselle ; Krug, Loane Dantas ; Nunes, Tiago Calves ; da Silva, Abimael Gomes ; Moreira, Silvino Intra ; Goncalves, Lucas Matheus de Deus Paes ; Silva, Tatiane Carla ; Ceresini, Paulo Cezar

• Tipo de documento: Artigo Científico
• Fonte: AGRONOMY-BASEL; v. 12, n. 6, p. 15-pg., 2022-06-01.

Resumo

Biological control is considered the only viable integrated disease management practice for controlling the widely distributed and destructive foliar blight and sudden death disease caused by the fungus Rhizoctonia solani AG-1 IA on signal grass (Urochloa brizantha) pastures. Since major signal grass varieties are highly susceptible and fungicide sprays are not labeled for grass pasture cropping systems, biological control is sought as an alternative for managing this fungal disease. In this study, 24 fluorescent Pseudomonas isolates obtained from naturally suppressive soils from the Amazon biome were bio-prospected for their role as biocontrol agents against R. solani AG-1 IA. Based on in vitro antagonism, three isolates (Amana, Poti, and Yara) were selected for further in vivo assays. Multilocus phylogenetic analysis indicated that Amana and Yara were grouped into the Pseudomonas putida group while Poti was grouped into the Pseudomonas asplenii group, and could well constitute a new Pseudomonas species. For in vivo biocontrol assays, the biocontrol agents were applied either via seed-treatment or via foliar spray. All three isolates produced siderophores and solubilized phosphate, while Amana and Poti showed protease and chitinase in vitro activity. Foliar application of P. putida Amana from Amazonian suppressive soils resulted in a significant reduction of the foliar blight disease severity on signal grass. We discuss further steps for the development and labeling of Pseudomonas-based biofungicides for managing the foliar blight disease on signal grass pastures in Brazil. (AU)

• Processo FAPESP: 17/03403-0 - Bioprospecção de bactérias fluorescentes do gênero Pseudomonas para o biocontrole da queima-das-folhas da braquiária (Urochloa brizantha)
• Beneficiário: Samara Nunes Campos Vicentini
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 11/50150-3 - A origem de populações emergentes do patógeno da queima da folha da Brachiaria spp. (Rhizoctonia solani AG-1) na Amazônia e seu potencial de adaptação a outros agroecossistemas brasileiros
• Beneficiário: Paulo Cezar Ceresini
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Regular
• Processo FAPESP: 11/23050-8 - A origem de populações emergentes do patógeno da queima da folha da Brachiaria spp. (Rhizoctonia solani AG-1 IA) na Amazônia e seu potencial de adaptação a outros agroecossistemas brasileiros
• Beneficiário: Edisson Chavarro Mesa
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 13/11944-0 - Estrutura genética de populações de Rhizoctonia oryzae-sativae do arroz no Vale do Paraíba, SP, e potencial adaptativo do patógeno à Brachiaria.
• Beneficiário: Danilo Augusto dos Santos Pereira
• Modalidade de apoio: Bolsas no Brasil - Mestrado