Volatile Emissions and Chlorophyll Fluorescence as Indicators of Freezing Injury in Apple Fruit

in HortScience
View More View Less
  • 1 Agriculture and Agri-Food Canada, Atlantic Food and Horticulture Research Centre, 32 Main Street, Kentville, N.S., B4N 1J5, Canada
  • 2 Agriculture and Agri-Food Canada, Atlantic Food and Horticulture Research Centre, 32 Main Street, Kentville, N.S., B4N 1J5, Canada
  • 3 Agriculture and Agri-Food Canada, Horticultural Research and Development Centre, 430 Gouin Blvd., Saint-Jean-sur-Richelieu, Québec J3B 3E6, Canada

Use of volatile emissions and chlorophyll fluorescence as indicators of freezing injury were investigated for apple fruit (Malus ×domestica Borkh.). `Northern Spy' and `Delicious' apples were kept at -8.5 °C for 0, 6, or 24 h, and then at 20 °C. After 1, 2, 5, and 7 d at 20 °C, fruit were analyzed for firmness, skin and flesh browning, soluble solid content, titratable acidity, ethanol, ethyl acetate, ethylene, respiration rate, and chlorophyll fluorescence. Freezing caused skin and flesh browning and a loss of fruit firmness, which was greater in `Northern Spy' than in `Delicious'. In `Northern Spy' fruit subjected to the freezing treatments, ethanol and ethyl acetate concentrations were as much as 37- and 300-fold greater, respectively, than in control fruit. `Delicious' fruit showed similar patterns of ethanol and ethyl acetate increase, but of lower magnitude, as a result of freezing. Higher fruit respiratory quotients were associated with increased ethanol and ethyl acetate concentrations. Ethylene production and chlorophyll fluorescence of fruit were reduced by freezing.

If the inline PDF is not rendering correctly, you can download the PDF file here.

Contributor Notes

To whom requests for reprints should be addressed. E-mail address: forneyc@em.agr.ca
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 165 58 3
PDF Downloads 351 43 8