Effect of fruit position in the canopy on physiological age and physicochemical composition of mango 'Cogshall'
Abstract
By comparing 3 harvest stages for mango, corresponding to two green mature stages (106 and 120 days after full bloom) and one stage at the onset of the climacteric rise (called 'yellow point' for Cv Cogshall), we demonstrated relationships between harvest stage and changes in some ripening and sensorial descriptors according to fruit position in the canopy (fruit and its fruit-bearing branch were either well-exposed to light or within the canopy, treatments named well-exposed and shaded fruit, respectively). Dry matter content and final sugar content (mainly sucrose) were lower in shaded fruit. Similar aromatic compounds were found in ripe fruit, but their contents depended on the fruit position in the canopy. Total aroma content decreased with the harvest stage, but this decrease was mainly due to the drop off of terpens content, the most abundant class. After ripening shaded fruit had a lower content in terpens (especially ?-3-carene) and a lower lactones content compared to well-exposed fruit. Most of these differences decreased with the harvest stage and were minimized at the latest harvest, corresponding to the yellow point stage. These results showed that the environmental conditions have an effect on the building and the growing of mango fruit in a same tree, and so on their physiological ages. An adapted pruning to facilitate access to light in the canopy is particularly important to obtain homogeneous batches. Moreover, the mixing of well-exposed and shaded fruits harvested at different "green mature" stages will induce heterogeneity and differences in quality of ripe fruit for the marketing network. (Résumé d'auteur)