Calcium chloride treatment modifies cell wall metabolism and activates defense responses in strawberry fruit (Fragaria x ananassa, Duch).
Langer, S. E., Marina, M., Burgos, J. L., Martinez, G. A., Civello, P. M. and Villarreal, N. M.
INTECH (CONICET-UNSAM), Instituto Tecnologico de Chascomus, Avenida Intendente Marino km 8,2, B7130IWA, Chascomus, Pcia. Buenos Aires, Argentina.
INFIVE (CONICET-UNLP), Instituto de Fisiologia Vegetal, Diag. 113 N degrees 495 - C.c 327, 1900 La Plata, Argentina.
Facultad de Ciencias Exactas, (UNLP), 47 y 115, 1900 La Plata, Argentina.
BACKGROUND:Fruit dips in calcium ions solutions have been shown as an effective treatment to extend strawberries (Fragaria x ananassa, Duch) quality during storage. In the present work, strawberry fruit were treated with 10 g L(-1) calcium chloride solution and treatment effects on cell wall enzymes activities and the expression of encoding genes, as well as enzymes involved in fruit defense responses were investigated. RESULTS: Calcium treatment enhanced pectin methylesterase activity while inhibited those corresponding to pectin hydrolases as polygalacturonase and beta-galactosidase. The expression of key genes for strawberry pectin metabolism was up- (for FaPME1) and down- (for FaPG1, FaPLB, FaPLC, FabetaGal1 and FaAra1) regulated by calcium dips. In agreement, a higher firmness level and ionically-bound pectins (IBP) amount were detected in calcium-treated fruit compared with controls. The in vitro and in vivo growth rate of fungal pathogen Botrytis cinerea was limited by calcium treatment. Moreover, the activities of polyphenol oxidases, chitinases, peroxidases and beta-1,3-glucanases were enhanced by calcium ions dips. CONCLUSION: News insights concerning the biochemical and molecular basis of cell wall preservation and resistance to fungal pathogens on calcium-treated strawberries are provided. This article is protected by copyright. All rights reserved.
Journal of the Science of Food and Agriculture : en prensa (2019)