VARIABILITY OF INTERNAL ETHYLENE CONCENTRATION AS A PARAMETER OF MATURITY IN APPLES.

It has been proposed that the analysis of internal ethylene concentration (IEC) can be used to determine the optimum harvest dates (OHD) and to predict the potential storage life of apples in normal or controlled atmosphere (CA). The IEC of some commercial apple cultivars grown in the Lleida province was studied, to determine its possible use as a maturity parameter in this area and its relation to other quality parameters.

Different varieties were studied during three seasons.
In the first year (1986) the results were variable depending on the cultivar.
For some varieties, the possibility of using the IEC as a maturity index was clear.
No significant changes were observed in IEC in other varieties while the fruit was on the tree.
However, in the varieties that showed significant changes in IEC, the results as a whole were not confirmed in following years.
Comparison between IEC and the evolution of other parameters indicates that soluble solids, firmness, etc, are more consistent to determine the development of fruit than IEC. Another aspect of the use of IEC as a maturity parameter is the variability shown by fruit of the same variety grown in a given area, but in different fields.

Measurement of the precursor of ethylene, ACC, shows an increase that precedes IEC and in some varieties could be used as a better reference than IEC. Nevertheless, measurement of ACC is too complex for practical purposes.

International Symposium on Pre- and Postharvest Physiology of Pome-fruit

J. Graell, I. Recasens, J. Salas, M. Vendrell

https://doi.org/10.17660/ActaHortic.1993.326.30