Ontogenetic Changes in Respiratory Pathways in Cortland Apple Skin during Storage

Ontogenic changes in respiratory pathways of skins of detached apple fruits were measured during a 4 month period. Results showed that an increase in pentose pathway occurred with increasing senescence in this tissue. Variation in temperature at any given age did not result in an alteration of the $\text{C}_{6}/\text{C}_{1}$ ratio. CO2 evolution from the pentose pathway in senescent fruit was directly related to O2 uptake. Glucose uptake increased with increasing senescence indicating a change in cell permeability.