title: Defence responses in rice plants in prior and simultaneous applications of Cladosporium sp. during leaf blast suppression.
abstract: An alternative method to control rice blast (Magnaporthe oryzae) is to include biological agent in the disease management strategy. The objective of this study was to assess the leaf blast-suppressing effects of rice phylloplane fungi. One Cladosporium sp. phylloplane fungus was shown to possess biocontrolling traits based on its morphological characteristics and an analysis of its 18S ribosomal DNA. Experiments aimed at determining the optimal time to apply the bioagent and the mechanisms involved in its rice blast-suppressing activities were performed under controlled greenhouse conditions. We used foliar spraying to apply the Cladosporium sp. 48 h prior to applying the pathogen, and we found that this increased the enzymatic activity. Furthermore, in vitro tests performed using isolate C24 showed that it possessed the ability to secrete endoxylanases and endoglucanases. When Cladosporium sp. was applied either prior to or simultaneous with the pathogen, we observed a significant increase in defence enzyme activity, and rice blast was suppressed by 84.0 and 78.6 %, respectively. However, some enzymes showed higher activity at 24 h while others did so at 48 h after the challenge inoculation. Cladosporium sp. is a biological agent that is capable of suppressing rice leaf blast by activating biochemical defence mechanisms in rice plants. It is highly adapted to natural field conditions and should be included in further studies aimed at developing strategies to support ecologically sustainable disease management and reduce environmental pollution by the judicious use of fungicidal sprays.
authors: Genetics of Microorganism Laboratory, Federal University of Goiás, Rodovia Goiânia/Nova Veneza, km 0. Goiânia, Goiás, 74001-970, Brazil.
authors: Amanda Abdallah
authors: AA
authors: Chaibub
authors: Genetics of Microorganism Laboratory, Federal University of Goiás, Rodovia Goiânia/Nova Veneza, km 0. Goiânia, Goiás, 74001-970, Brazil.
authors: Jacqueline Campos Borba
authors: JC
authors: de Carvalho
authors: Genetics of Microorganism Laboratory, Federal University of Goiás, Rodovia Goiânia/Nova Veneza, km 0. Goiânia, Goiás, 74001-970, Brazil.
authors: Carlos
authors: C
authors: de Sousa Silva
authors: Genetics and Biodiversity Laboratory, Federal University of Goiás, Rodovia Goiânia/Nova Veneza, Km 0. Goiânia, Goiás, 74001-970, Brazil.
authors: Rosane Garcia
authors: RG
authors: Collevatti
authors: Plant Pathology and Microbiology Laboratory at Embrapa Rice and Beans, Rodovia GO-462, km 12 Zona Rural C.P. 179, Cep, Santo Antônio de Goiás, GO, 75375-000, Brazil.
authors: Fábio José
authors: FJ
authors: Gonçalves
authors: Plant Pathology and Microbiology Laboratory at Embrapa Rice and Beans, Rodovia GO-462, km 12 Zona Rural C.P. 179, Cep, Santo Antônio de Goiás, GO, 75375-000, Brazil.
authors: Márcio Vinícius
authors: MV
authors: de Carvalho Barros Côrtes
authors: Plant Pathology and Microbiology Laboratory at Embrapa Rice and Beans, Rodovia GO-462, km 12 Zona Rural C.P. 179, Cep, Santo Antônio de Goiás, GO, 75375-000, Brazil. cristina.filippi@embrapa.br.
authors: Marta Cristina Corsi
authors: MC
authors: de Filippi
authors: Fungi Biotechnology Laboratory, Rodovia Goiânia / Nova Veneza, Km 0. Goiânia, Goiás, 74001-970, Brazil.
authors: Fabrícia Paula
authors: FP
authors: de Faria
authors: Fungi Biotechnology Laboratory, Rodovia Goiânia / Nova Veneza, Km 0. Goiânia, Goiás, 74001-970, Brazil.
authors: Douglas Christian Borges
authors: DC
authors: Lopes
authors: Genetics of Microorganism Laboratory, Federal University of Goiás, Rodovia Goiânia/Nova Veneza, km 0. Goiânia, Goiás, 74001-970, Brazil.
authors: Leila Garcês
authors: LG
authors: de Araújo
mesh_terms: D061046:Biological Control Agents / Q000145:classification / Q000494:pharmacology*; D002963:Cladosporium / Q000502:physiology*; D020082:Magnaporthe / Q000502:physiology*; D012275:Oryza / Q000276:immunology / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology / Q000517:prevention & control*; D057865:Plant Immunity; D018515:Plant Leaves / Q000382:microbiology
chemical_list: D061046:Biological Control Agents
keywords: Antagonism; Biological agent; Magnaporthe oryzae; Oryza sativa; Resistance induction; Sustainable management