How does tomato quality (sugar, acid, and nutritional quality) vary with ripening stage, temperature, and irradiance?
The objective of this study was to understand the respective impact of ripening stage, temperature, and irradiance on seasonal variations of tomato fruit quality. During ripening, concentrations in reducing sugars, carotenes, ascorbate, rutin, and caffeic acid derivates increased, whereas those in titratable acidity, chlorophylls, and chlorogenic acid content decreased. Fruit temperature and irradiance affected final fruit composition. Sugars and acids (linked to fruit gustative quality) were not considerably modified, but secondary metabolites with antioxidant properties were very sensitive to fruit environment. Increased fruit irradiance enhanced ascorbate, lycopene, beta-carotene, rutin, and caffeic acid derivate concentrations and the disappearance of oxidized ascorbate and chlorophylls. Increasing the temperature from 21 to 26 degrees C reduced total carotene content without affecting lycopene content. A further temperature increase from 27 to 32 degrees C reduced ascorbate, lycopene, and its precursor's content, but enhanced rutin, caffeic acid derivates, and glucoside contents. The regulation by light and temperature of the biosynthesis pathways of secondary metabolites is discussed.
Gautier
Hélène
H
INRA, UR1115 Plantes et Systèmes de culture Horticoles, Domaine St. Paul, Site Agroparc, Avignon, France. gautier@avignon.inra.fr
Diakou-Verdin
Vicky
V
Bénard
Camille
C
Reich
Maryse
M
Buret
Michel
M
Bourgaud
Frédéric
F
Poëssel
Jean Luc
JL
Caris-Veyrat
Catherine
C
Génard
Michel
M
D000975:Antioxidants / Q000032:analysis; D001205:Ascorbic Acid / Q000032:analysis; D002109:Caffeic Acids / Q000032:analysis; D002241:Carbohydrates / Q000032:analysis; D002338:Carotenoids / Q000032:analysis; D002726:Chlorogenic Acid / Q000032:analysis; D005514:Food Irradiation; D018551:Solanum lycopersicum / Q000737:chemistry* / Q000502:physiology; D009753:Nutritive Value; D012431:Rutin / Q000032:analysis; D012621:Seasons; D013696:Temperature; D013997:Time Factors
D000975:Antioxidants; D002109:Caffeic Acids; D002241:Carbohydrates; D002726:Chlorogenic Acid; D002338:Carotenoids; D012431:Rutin; D001205:Ascorbic Acid; C040048:caffeic acid