Ethylene and Carbon Dioxide Production in Detached Fruit of Selected Pepper Cultivars

Bell peppers ( Capsicum annuum L.) are classified as nonclimacteric fruits while some hot peppers have been reported as climacteric. Responses of peppers to exogenously applied ethylene-releasing compounds suggest ethylene involvement in the ripening process. Ethylene production and respiration rates in 13 cultivars of pepper: `Camelot', `Cherry Bomb', `Chiltepin', `Cubanelle', `Banana Supreme', `Habanero', `Hungarian Wax', `Mesilla', `Mitla', `Savory', `Sure Fire', `Tabasco', and `King Arthur' were studied under greenhouse and field conditions. Fruit from each cultivar were harvested at different maturity stages determined by color, ranging from mature-green to full red-ripe. Carbon dioxide and ethylene production were measured by gas chromatography. Both variables were significantly different among maturity stages for all cultivars. Respiration rates were between 16.5 and 440.3 mg·kg -1 ·h -1 CO 2 . Ethylene production ranged from 0.002 to 1.1 μL·kg -1 ·h -1 . Two patterns of CO 2 production were identified: higher CO 2 production for mature-green fruit with successive decreases for the rest of the maturity stages or lower respiration rates for mature-green fruit with an increase in CO 2 production either when fruit were changing color or once fruit were almost totally red. A rise in CO 2 production was present for most cultivars. Ethylene evolution increased significantly at maturity or before maturity in all cultivars except `Cubanelle' and `Hungarian Wax'. Respiration rates and ethylene production were significantly different among cultivars at the mature-green and red stages.