To access the full text documents, please follow this link:

Acidification of apple and orange hosts by Penicillium digitatum and Penicillium expansum.
Vilanova, Laura; Viñas Almenar, Inmaculada; Torres Sanchis, Rosario; Usall i Rodié, Josep; Burón Moles, Gemma; Teixidó i Espasa, Neus
New information about virulence mechanisms of Penicillium digitatum and Penicillium expansum could be an important avenue to control fungal diseases. In this study, the ability of P. digitatum and P. expansum to enhance their virulence by locally modulating the pH of oranges and appleswas evaluated. For each host, pH changeswith a compatible pathogen and a non-host pathogen were recorded, and the levels of different organic acids were evaluated to establish possible relationships with host pH modifications. Moreover, fruits were harvested at three maturity stages to determine whether fruit maturity could affect the pathogens' virulence. The pH of oranges and apples decreasedwhen the compatible pathogens (P. digitatumand P. expansum, respectively) decayed the fruit. The main organic acid detected in P. digitatum-decayed oranges was galacturonic acid produced as a consequence of host maceration in the rot development process. However, the obtained results showed that this acid was not responsible for the pH decrease in decayed orange tissue. The mixture of malic and citric acids could at least contribute to the acidification of P. digitatum-decayed oranges. The pH decrease in P. expansum decayed apples is related to the accumulation of gluconic and fumaric acids. The pH of oranges and apples was not affected when the non-host pathogen was not able to macerate the tissues. However, different organic acid contents were detected in comparison to healthy tissues. The main organic acids detected in P. expansum
oranges were oxalic and gluconic and in P. digitatum
apples were citric, gluconic and galacturonic. Further research is needed to identify the pathogenicity factors of both fungi because the contribution of organic acids has profound implications.
Green mold
Blue mold
Maturity stage
Host acidification
Fisiologia postcollita
Àcids orgànics
Postharvest physiology
Organic acids
(c) Elsevier, 2014

Full text files in this document

Files Size Format View
022564.pdf 1.046 MB application/pdf View/Open

Show full item record

Related documents

Other documents of the same author