RESUMO
This study aimed to investigate the mycoparasitism of Botrytis cinerea, the pathogen of scape and umbel blights of onion seed crops, by endophytic Talaromyces pinophilus. The dual culture test showed that the antagonistic potentiality of T. pinophilus against B. cinerea depend on the mycoparasitism that was morphologically detected by the formation of mycelial overgrowth. Moreover, the light micrograph of the mycelia at the contact zone exhibited that the hyphae of T. pinophilus penetrated and grew intracellularly inside the hyphae of B. cinerea. A more illustrative figure of the establishment of coiled hyphae as well as the conformation of the penetration process was assayed by SEM and TEM analyses. SEM micrograph revealed that the hyphae of T. pinophilus grew along hyphae of B. cinerea, attached, coiled around the host hypha and generated pseudoappressorium. A clear disintegration of cell wall of the host hypha was observed at the penetration site. The micrographs of TEM exhibited the ability of T. pinophilus to produce pseudoappressorium, penetrate and then entere a hypha of B. cinerea causing distinct cytoplasmic disorganization. High activities of cell wall degrading enzymes (chitinase, lipase and protease) involved in the mycoparasitism were evaluated by the endophytic T. pinophilus. In conclusion, this study demonstrated that the endophytic T. pinophilus may be a promising biocontrol agent against phytopathogenic fungi instead of chemical fungicides.
Assuntos
Antibiose , Botrytis/patogenicidade , Cebolas/microbiologia , Controle Biológico de Vetores , Doenças das Plantas/microbiologia , Talaromyces/fisiologia , Botrytis/citologia , Botrytis/crescimento & desenvolvimento , Botrytis/isolamento & purificação , Parede Celular , Quitinases/metabolismo , Técnicas de Cocultura , DNA Fúngico , Egito , Endófitos , Fungicidas Industriais , Hifas/citologia , Hifas/crescimento & desenvolvimento , Lipase/metabolismo , Microscopia Eletrônica , Micélio/crescimento & desenvolvimento , Peptídeo Hidrolases/metabolismo , Controle Biológico de Vetores/métodos , Talaromyces/citologia , Talaromyces/enzimologia , Talaromyces/isolamento & purificaçãoRESUMO
Two novel biverticillate Talaromyces species, T. angelicus and T. cnidii, were collected from the medicinal crops Angelica gigas and Cnidium officinale, respectively, in Korea. Phylogenetic analyses with the nuclear ribosomal internal transcribed spacer (ITS) region and the ß-tubulin gene as well as morphological analyses revealed that the two species differ from any known Talaromyces species. Talaromyces angelicus is related to T. flavovirens in the phylogeny of the ITS region, but the new species is grouped together with Penicillium liani and T. pinophilus in terms of its ß-tubulin phylogeny, and its growth rate on Czapek yeast autolysate differs from that of T. flavovirens. Talaromyces cnidii is phylogenetically similar to T. siamensis, but exhibits differences in the morphologies of the colony margin, metulae, and conidia.