TY - JOUR

T1 - Calcium ions decrease water-soaking in strawberries

AU - Hurtado, Grecia

AU - Knoche, Moritz

N1 - Funding Information: The funding of this study was provided by grant nr. KN402/19-1 (to MK) from the German Science Foundation (DFG). The publication of this article was funded by the Open Access fund of the Leibniz Universita ̈t Hannover. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. There was no additional external funding received for this study. Acknowledgments: We thank Heike, Karl Walter and Martin Bru ̈ggenwirth and Bendix Meyer for the gift of fruit, Marcel Pasta and Peter Grimm-Wetzel for technical support and Drs. Sandy Lang and Andreas Winkler for helpful comments on an earlier version of this manuscript.

PY - 2022/8

Y1 - 2022/8

N2 - Water soaking is a common disorder of field-grown strawberries (Fragaria × ananassa Duch.). It develops when ripe fruit is exposed to rain. Here we investigate the effects of Ca on water soaking. Fruit was incubated in solutions of various Ca salts and the extent of water soaking quantified using a simple rating scheme. Exposure to CaCl2 (10 mM) decreased water soaking and anthocyanin leakage but had no effect on water uptake. The decrease in water soaking due to CaCl2 was not limited to a single cultivar but occurred in all cultivars examined. Incubating fruit in a chelating agent (EGTA) increased water soaking compared to the water control. Calcium salts of different acids varied in their effects on water soaking. Only CaCl2 reduced water soaking significantly. The chlorides of different cations, also varied in their effects on water soaking. Those of the monovalent cations had no effects on water soaking, while those of the divalent cations (CaCl2, BaCl2 and SrCl2) and of the trivalent cations (FeCl3 and AlCl3) were all effective in decreasing water soaking. Overall, CaCl2 decreased microcracking of the strawberry cuticle as compared to deionized water. Furthermore, CaCl2 also reduced the leakage of anthocyanins from flesh discs, irrespective of the osmotic potential of the incubation solution. Our results indicate that CaCl2 reduced water soaking by decreasing cuticular microcracking, by decreasing leakage of plasma membranes and, possibly, by increasing the crosslinking of cell wall constituents.

AB - Water soaking is a common disorder of field-grown strawberries (Fragaria × ananassa Duch.). It develops when ripe fruit is exposed to rain. Here we investigate the effects of Ca on water soaking. Fruit was incubated in solutions of various Ca salts and the extent of water soaking quantified using a simple rating scheme. Exposure to CaCl2 (10 mM) decreased water soaking and anthocyanin leakage but had no effect on water uptake. The decrease in water soaking due to CaCl2 was not limited to a single cultivar but occurred in all cultivars examined. Incubating fruit in a chelating agent (EGTA) increased water soaking compared to the water control. Calcium salts of different acids varied in their effects on water soaking. Only CaCl2 reduced water soaking significantly. The chlorides of different cations, also varied in their effects on water soaking. Those of the monovalent cations had no effects on water soaking, while those of the divalent cations (CaCl2, BaCl2 and SrCl2) and of the trivalent cations (FeCl3 and AlCl3) were all effective in decreasing water soaking. Overall, CaCl2 decreased microcracking of the strawberry cuticle as compared to deionized water. Furthermore, CaCl2 also reduced the leakage of anthocyanins from flesh discs, irrespective of the osmotic potential of the incubation solution. Our results indicate that CaCl2 reduced water soaking by decreasing cuticular microcracking, by decreasing leakage of plasma membranes and, possibly, by increasing the crosslinking of cell wall constituents.

UR - http://www.scopus.com/inward/record.url?scp=85135951123&partnerID=8YFLogxK

U2 - 10.1371/journal.pone.0273180

DO - 10.1371/journal.pone.0273180

M3 - Article

C2 - 35969592

AN - SCOPUS:85135951123

VL - 17

JO - PLOS ONE

JF - PLOS ONE

SN - 1932-6203

IS - 8 August

M1 - e0273180

ER -