Chlorophyll Fluorescence in Relation to Superficial Scald Development in Apple

in Journal of the American Society for Horticultural Science
View More View Less
  • 1 Department of Horticulture, Michigan State University, East Lansing, MI 48824

The relationship between chlorophyll fluorescence of `Cortland', `Redchief Delicious', and `Empire' apple (Malus ×domestica Borkh.) fruit and the development of superficial scald was studied during 120 days of refrigerated air (RA) storage at 0 °C and during 7 days of poststorage holding at 22 °C. Minimal fluorescence (Fo), maximal fluorescence (Fm), photochemical efficiency (Fv/Fm, where Fv=Fm=Fo) and coefficient of photochemical fluorescence quenching (qp) were measured. During storage, while Fv/Fm and Fm declined in `Cortland' and `Redchief Delicious' fruit over time, these two measures of chlorophyll fluorescence remained stable in `Empire' fruit. Of the three cultivars, only `Empire' is resistant to and did not develop superficial scald. A decline in Fv/Fm preceded scald development in `Cortland' and `Redchief Delicious' fruit. After 30 days of storage, qp began to decrease in fruit from all three cultivars. Prestorage diphenylamine (DPA) application had no effect on Fv/Fm, Fo, and Fm and only marginally improved maintenance of qp, but completely prevented the development of superficial scald. Poststorage holding at 22 °C accelerated the rate of change in most fluorescence measurements. The decline in the Fv/Fm ratio and/or qp with storage time may be in response to senescence-related factors that also enhance scald susceptibility, however, Fv/Fm does not appear to be directly related to superficial scald susceptibility per se.

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

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 72 45 1
PDF Downloads 35 11 4