Cross-tolerance and antioxidant metabolism as determinants of the resistance of apple fruit to postharvest Botrytis decay

• Published in: Acta horticulturae no. 9341; pp. 319 - 326
• Main Authors: Tuyet, B.T.A, Vanwalleghem, T, Vorstemans, B, Creemers, P, Hertog, M, Nicolaï, B, Keulemans, J, Davey, M.W
• Format: Journal Article
• Language: English
• Published: International Society for Horticultural Science 2012
• Subjects: apples; ascorbic acid; Botrytis cinerea; cultivars; enzymes; metabolism; metabolites; phenolic compounds; reactive oxygen species; storage quality
• ISSN: 0567-7572

In apple, fruit storage properties and susceptibility to post-harvest phytopathogens differ substantially between cultivars, but little is generally understood about the molecular basis of these differences. Recently we have shown that there is a correlation between fruit vitamin C (L-ascorbic acid, AsA), and antioxidant contents with several aspects of postharvest quality. This relationship between elevated antioxidant contents and an improved (a)biotic stress-resistance during postharvest may be related to the capacity of tissues to deal with the consequences of H2O2-production resulting from infection and/or storage stresses. Here we report on the results of a comprehensive analysis of the responses of fruit antioxidant metabolism following infection with Botrytis cinerea in the apple cultivars 'Golden Delicious' and 'Braeburn'. Results suggest that pre-harvest exposure to high-light/high temperature stress can induce cross-tolerance to post-harvest B. cinerea infection. Quantification of the major fruit flesh antioxidant metabolites (ascorbic acid, phenolics) and of the activities of enzymes involved in the detoxification of reactive oxygen species help us to understand possible involvement of antioxidant metabolism in resistance and the response of tissues to infection.