ce:italic>Talaromyces pinophilus/ce:italic> strain AUN-1 as a novel mycoparasite of ce:italic>Botrytis cinerea/ce:italic>, the pathogen of onion scape and umbel blights

摘要

This study aimed to investigate the mycoparasitism ofBotrytis cinerea,the pathogen of scape and umbel blights of onion seed crops, by endophyticTalaromyces pinophilus. The dual culture test showed that the antagonistic potentiality ofT. pinophilusagainstB. cinereadepend 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 ofT. pinophiluspenetrated and grew intracellularly inside the hyphae ofB. 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 ofT. pinophilusgrew along hyphae ofB. 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 ofT. pinophilusto produce pseudoappressorium, penetrate and then entere a hypha ofB. cinereacausing distinct cytoplasmic disorganization. High activities of cell wall degrading enzymes (chitinase, lipase and protease) involved in the mycoparasitism were evaluated by the endophyticT. pinophilus. In conclusion, this study demonstrated that the endophyticT. pinophilusmay be a promising biocontrol agent against phytopathogenic fungi instead of chemical fungicides.