title: Influence of the preservation period in silica-gel on the predatory activity of the isolates of Duddingtonia flagrans on infective larvae of cyathostomins (Nematoda: Cyathostominae).
abstract: The continued maintenance of nematophagous fungi predatory activity under laboratory conditions is one of the basic requirements for a successful biological control. The purpose of this study was to evaluate the influence of time on the preservation of the fungus Duddingtonia flagrans (AC001 and CG722) stored in silica-gel for 7 years and their subsequent predatory activity on cyathostomin L(3) larvae in 2% water-agar medium (2% WA). Samples of the isolates AC001 and CG722, originating from vials containing grains of silica-gel sterilized and stored for 7 years, were used. After obtaining fungal conidia, the predation test was conducted over 7 days on the surface of 9.0 cm Petri dishes filled with 2% WA. In the treated groups each Petri dish contained 500 cyathostomin L(3) and conidia of fungal isolates in 2% WA. In the control group (without fungi) the plates contained 500 L(3) in 2% WA. The experimental results showed that isolated AC001 and CG722 were efficient in preying on cyathostomin L(3) (p<0.01) compared to control (without fungus). However, no difference was observed (p>0.01) in the predatory activity of the fungal isolates tested. Comparing the groups, there was a significant reductions of cyathostomin L(3) (p<0.01) of 88.6% and 78.4% on average recovered from the groups treated with the isolates AC001 and CG722, respectively, after 7 days. The results of this test showed that the fungus D. flagrans (AC001 and CG722) stored in silica-gel for at least 7 years maintained its predatory activity on cyathostomin L(3).
authors.affiliation: Departamento de Veterinária, Universidade Federal de Viçosa, Viçosa-MG, CEP 36570-000 Vicosa, Brazil. fabioribeirobraga@hotmail.com
authors.forename: Fabio Ribeiro
authors.initials: FR
authors.lastname: Braga
authors.forename: Jackson Victor
authors.initials: JV
authors.lastname: Araújo
authors.forename: Juliana Milani
authors.initials: JM
authors.lastname: Araujo
authors.forename: Alexandre de Oliveira
authors.initials: Ade O
authors.lastname: Tavela
authors.forename: Sebastião Rodrigo
authors.initials: SR
authors.lastname: Ferreira
authors.forename: Filippe E
authors.initials: FE
authors.lastname: Freitas Soares
authors.forename: Laércio dos Anjos
authors.initials: Ldos A
authors.lastname: Benjamin
authors.forename: Luiza Neme
authors.initials: LN
authors.lastname: Frassy
mesh_terms: D000818:Animals; D001203:Ascomycota / Q000254:growth & development / Q000472:pathogenicity*; D005243:Feces / Q000469:parasitology; D006736:Horses; D007814:Larva / Q000382:microbiology; D010572:Pest Control, Biological / Q000592:standards; D011309:Preservation, Biological; D058428:Silica Gel; D013172:Spores, Fungal / Q000254:growth & development / Q000472:pathogenicity; D013319:Strongyle Infections, Equine / Q000469:parasitology*; D013320:Strongyloidea / Q000382:microbiology*; D013997:Time Factors
chemical_list: D058428:Silica Gel