QUALITY DETERMINATIONS AND FLUORIMETRIC MEASUREMENTS TO ASSESS THE SENSITIVITY OF PEAR TO INTERNAL DISORDERS

The objective of this work was to relate chlorophyll fluorescence parameters to quality parameters and to analyse their respective potential to detect stress and predict internal disorder occurrence in pears.
For this purpose, batches of 400 fruit of ‘Williams Bon Chrétien’, ‘Beurre Bosc’ and ‘Doyenne du Comice’ pears were harvested in Nelson (New Zealand). The fruit were stored immediately at 0°C in air (RA) or in controlled atmosphere at 2% O₂ and 5% CO₂. At harvest and after 3, 15, 30 and 60 days in storage, fluorescence parameters (F0, Fm, Fv and ratio Fv/Fm) were measured using a Pulse Amplified Modulation fluorometer.
The quality parameters measured were firmness, titratable acidity, soluble solids content and starch index. ‘Williams Bon Chrétien’ pears exhibited a higher decrease in Fv/Fm ratio after 30 days of storage.
This difference was associated with higher incidence of disorder than in the two other cultivars.
The same overall pattern was also found in RA storage but with lower disorder incidence compared to CA. ‘Doyenne du Comice’ and ‘Beurre Bosc’ pears exhibited few disorders and in general quality parameters did not relate to stress occurrence in the fruit or to internal browning.
These results indicate that fluorimetry may be an interesting technique to detect stress in pear and to predict internal disorder occurrence in pear in a better way than with the use of classic quality measurements.

VI International Postharvest Symposium

G. Cascia, W. Schotsmans, C. Larrigaudière, J. Johnston

chlorophyll fluorescence, quality, internal disorders, pears, air, controlled atmosphere

https://doi.org/10.17660/ActaHortic.2010.877.188