DIE VERTEILUNG DER SAUERSTOFFKONZENTRATION IN REIFENDEN ÄPFELN

• Published in: Planta 1965-01, Vol.65 (1), p.65-72
• Main Authors: Brändle, Roland, Wanner, Hans
• Format: Article
• Language: eng ; ger
• ISSN: 0032-0935; 1432-2048
• DOI: 10.1007/BF00385180

Oxygen concentrations in fleshy fruits can be measured accurately with a miniaturized Clark electrode. As the oxygen consumption of the electrode is practically nil, small local differences can be evaluated. In apples of different varieties, a steep gradient of oxygen concentration from the peel inwards can be demonstrated. The slope of this gradient decreases with the increasing radial distance from the epidermis. The gradient consistently shows a step in the zone of the vascular bundles. With the exception of the climacteric minimal oxygen concentrations near the carpels are above or near a value corresponding to a ${\mathrm{p}}_{{\mathrm{O}}_{2}}$ of 40 mm Hg (${\mathrm{p}}_{{\mathrm{O}}_{2}}$ in air 148—151 mm Hg depending on barometric pressure). During the climacteric, oxygen concentrations can sink to very low values, accompanied by an irregular radial distribution.