Observations on Gas Exchange in the Developing Sultana Berry

Abstract

In its early phases of growth the grape berry, although lacking stomata, shows measurable photosynthetic activity. There also exists a capacity for dark C02 fixation following a period of illumination and a relatively high rate of dark respiration (expressed as 02 uptake) with a respiratory quotient which is less than unity. Oxygen uptake can be completely arrested by illumination.