Mechanism of action of Metschnikowia pulcherrima strain mach1 against Botrytis cinerea on apple
D. Saravanakumar, A. Ciavorella, D. Spadaro, A.Garibaldi and M.L. Gullino.
Journal of Plant Pathology Volume 90 (2, Supplement) August 2008, Book of Abstract, 9th International Congress of Plant Pathology, August 24-29, 2008 Torino, Italy,. 507 pages.
2008
บทคัดย่อ
We studied the mechanism of action of the biocontrol yeast Metschnikowia pulcherrima strain MACH1 against grey mould (Botrtyis cinerea) on apple. We tested the ability of MACH1 to compete with the postharvest pathogen for acquisition of nutrients, especially for iron compounds. The yeast produced a pigment called pulcherrimin in presence of iron and showed antagonistic activity against B. cinerea in vitro and in vivo. Quantitative assay of extracellular enzymes from MACH1 culture filtrates showed that it was able to produce chitinase and beta-1,3-glucanase, and the study indicated the probable influence of these lytic enzymes in the biological control of grey mould. In addition, the state of host tissues in response to MACH1 treatment and challenge inoculation with B. cinerea was studied. The results revealed the greater accumulation of defense enzymes, peroxidase, polyphenol oxidase and phenylalanine ammonia lyase in apples treated with MACH1 and challenged with B. cinerea compared to untreated controls. The prolonged activity of defense enzymes in apples treated with MACH1 was able to limit the further growth of the pathogenic fungus in host tissues. In conclusion, the study revealed that competition for nutrients, production of extracellular enzymes and enhancement of host resistance by MACH1 could act together in the biological control of postharvest pathogens in apples.