Effect of ethylene on certain quality parameters of apricot fruit (Prunus armeniaca, L.) during maturation and postharvest evolution

Ethylene is a plant hormone which promotes a number of events in the fruit development. In climacteric fruits such as apricots the induction of ripening is associated with an increase in ethylene biosynthesis and respiration rate. Apricot fruit ripening involves several changes especially autolysis of cell wall pectin, synthesis of carotenoid pigments and degradation of chlorophyll. In order to evaluate the influence of ethylene on these parameters of maturity, two steps were done: firstly a comparison of the maturation characteristics on two contrasted apricot cultivars Moniqui and Bergeron and secondly a trial on the inhibition of ethylene action on Moniqui using 1-methylcyclopropene (1-MCP). During maturation, rapid fruit colour change and loss of firmness seemed to be correlated with a significant increase in ethylene production. The application of 1-MCP was found to efficiently inhibit ethylene production in the preclimacteric stages only. Concurrently, the colour of the fruit and its rate of softening were reduced. However, these results have to be confirmed by analysing the metabolic pathway of ethylene at the molecular level and studying the gene expression and regulation.