Crises respiratoires et maturation chez deux fruits (la poire et la cerise) cueillis à divers stades et conservés ensuite à temperature constante,en présence ou non d'éthylène

Respiratory behaviour and response to ethylene of two fruits was compared during growth and maturation. The first one, the cherry (var. Bigarreau Napoleon) is ‘non climacteric’. The second one, the pear (var. Passe-Crassane) is ‘climacteric’ and needs a certain period of cold for its usual maturation. Young cherries exhibit a natural respiratory rise after 4 or 5 days of storage but young pears do not. Breaf ethylene treatments involve a rise of respiration, more intense with the pear. As for ‘adult’ fruits the respiratory response varies but the effect on ripening is not established and, in our conditions, does not seen to be really significative. The following question can be asked. What are the relations between respiration (with or without a climacteric rise), the different ripening phenomena and the action and role of ethylene? More generally, it would be very interesting to study, in a comparative way, the ripening of climacteric and non climacteric fruits, with a special look at the factors promoting, delaying or preventing the normal course of ripening.