CO2 and C2H4 Evolution by Highbush Blueberry Fruit1

Highbush blueberries ( Vaccinium corymbosum L.) of 7 cultivars were harvested and visually separated into color grades: immature green, mature green, green-pink, blue-pink, blue and ripe. The rates of respiration over a 5 year period and ethylene evolution over a 3 year period of each color grade were determined using an infrared gas analyzer and a gas chromatograph, respectively. The rate of respiration of the berries generally increased from the immature green to a peak at the green-pink or blue-pink stage. Ethylene generally increased to a peak at green-pink. Both patterns are characteristic of climacteric type fruit.