title: Selection of endophytic fungi from comfrey (Symphytum officinale L.) for in vitro biological control of the phytopathogen Sclerotinia sclerotiorum (Lib.).
abstract: Biological control consists of using one organism to attack another that may cause economic damage to crops. Integrated Pest Management (IPM) is a very common strategy. The white mold produced by Sclerotinia sclerotiorum (Lib.) causes considerable damage to bean crops. This fungus is a soil inhabitant, the symptoms of which are characterized by water-soaked lesions covered by a white cottony fungal growth on the soil surface and/or the host plant. Possible biological control agents taken from plants are being investigated as phytopathogen inhibitors. These are endophytic microorganisms that inhabit the intercellular spaces of vegetal tissues and are often responsible for antimicrobial production. The objective of the present study was to select endophytic fungi isolated from comfrey (Symphytum officinale L.) leaves with in vitro antagonist potential against the phytopathogenic fungus S. sclerotiorum. Twelve isolates of endophytic fungi and a pathogenic strain of S. sclerotiorum were used in the challenge method. With the aid of this method, four endophytes with the best antagonistic activity against S. sclerotiorum were selected. Pathogen growth inhibition zones were considered indicative of antibiosis. The percentages of pathogenic mycelia growth were measured both with and without the antagonist, resulting in growth reductions of 46.7% to 50.0% for S. sclerotiorum. These analyses were performed by evaluating the endophytic/pathogenic mycelia growth in mm/day over an eight-day period of antagonistic tests.
authors.affiliation: Departamento de Biologia Estrutural, Molecular e Genética, Universidade Estadual de Ponta Grossa , Ponta Grossa, PR , Brasil.
authors.forename: Rafaeli
authors.initials: R
authors.lastname: Rocha
authors.forename: Daniela Eleutério
authors.initials: DE
authors.lastname: da Luz
authors.forename: Cibelle
authors.initials: C
authors.lastname: Engels
authors.forename: Sônia Alvim Veiga
authors.initials: SA
authors.lastname: Pileggi
authors.forename: David
authors.initials: D
authors.lastname: de Souza Jaccoud Filho
authors.forename: Rodrigo Rodrigues
authors.initials: RR
authors.lastname: Matiello
authors.forename: Marcos
authors.initials: M
authors.lastname: Pileggi
keywords: Sclerotinia sclerotiorum (Lib.); Symphytum officinale L; biological control; endophytic strain
references.citation: Appl Microbiol Biotechnol. 2001 Jul;56(1-2):58-68
references.pmid: 11499948
references.citation: Hippokrates. 1952 Oct 15;23(19):550-2
references.pmid: 12999159
references.citation: Proc Natl Acad Sci U S A. 1921 Jan;7(1):35-41
references.pmid: 16576575
references.citation: Annu Rev Phytopathol. 1992;30:603-35
references.pmid: 18647102
references.citation: Arch Mikrobiol. 1970;71(2):191-5
references.pmid: 5444096
references.citation: Rev Argent Microbiol. 1999 Jan-Mar;31(1):13-8
references.pmid: 10327455
references.citation: Can J Microbiol. 2004 Apr;50(4):239-49
references.pmid: 15213748
references.citation: Izv Akad Nauk Ser Biol. 2001 Jul-Aug;(4):435-41
references.pmid: 11525124
references.citation: J Basic Microbiol. 2004;44(2):157-60
references.pmid: 15069675