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• Eating quality of fruit is related to their dry matter content at the harvest. • The pulp color at the harvest is a good indicator of the fruit shelf life. • Fruit shelf life is not well predicted by their dry matter content at the harvest. • NIRS allows to predict the eating quality and shelf life of fruits at the harvest. Nondestructive methods such as near infrared spectroscopy (NIRS) are increasingly used in sorting lines to assess quality traits of unripe fruit, i.e. dry matter (DM) and total soluble solid (TSS) contents, in order to create homogenous batches of fruit. The use of this approach is based on the assumption that fruit quality traits at harvest are reliable indicators of their post-harvest behavior and their quality after ripening. The present study tested this assumption by analyzing the relationships between quality traits at harvest and after ripening. In parallel, models were developed to determine the capacity of NIRS measurements on unripe fruit at harvest to predict their shelf life and quality after ripening. The quality traits DM, TSS content, pulp color (PC) and titratable acidity (TA) of 92 mangoes from different harvests, production years, and orchards were compared at harvest and after ripening. Previously developed NIRS models were used to nondestructively assess the quality traits of the mangoes at harvest. New partial least squares (PLS) regressions using different variable selection procedures and preprocessing techniques were used to predict fruit shelf life and fruit quality after ripening based on NIRS measurements at harvest. Weak relationships (r² < 0.41) were found between fruit quality traits measured at harvest and after ripening, except for DM content (r² = 0.61). The PC of mango measured at harvest was found to be the best indicator of fruit shelf life. Errors of PLS regressions to predict the TSS content (RMSEV = 1.1%), titratable acidity (RMSEV = 0.52%), and the Hue angle of the flesh (RMSEV = 1.86°) were in the same range as those of linear regressions based on quality traits assessed at harvest except for PC. This work provides evidence that fruit maturity and quality should be assessed using different indicators. [ABSTRACT FROM AUTHOR]

Near infrared spectroscopy (NIRS) is increasingly being used with success in fruit supply chains for the non-destructive assessment of internal fruit quality. However, the prediction performance of NIRS was reported to be sensitive to changes in the pre- and post-harvest factors involved in fruit quality variations. This study attempted to establish robust NIRS models to predict mango internal quality, regardless of the conditions encountered by fruits on the tree and after harvest. A database involving mangoes (n = 250) from different production years and orchards and which were harvested at different maturity stages and stored at different temperatures for various periods was used to characterize mango quality using NIRS. The large variations measured in mango total soluble solid (TSS) content, dry matter, flesh color and acidity ensured that the dataset considered in this study covered differences in quality levels that can be encountered for the mango cultivar studied. Variable selection procedures and pre-processing techniques were used to improve the performance of the Partial Least Squares Regression (PLSR) models that accurately predicted the mango quality traits studied, regardless of the origins and storage conditions. The root mean square errors in prediction (RMSEP) were 0.6°Brix, 1.4%, 5.9 meq 100 g FM −1 and 3.16°Brix for the TSS content, dry matter content, titratable acidity and the hue angle of flesh color, respectively. The results presented in this study confirmed that robust NIRS models can be developed to predict mango quality by considering the pre- and post-harvest factors involved in fruit quality. Further studies should assess the use of NIR spectra on fruits to address internal quality variation issues, as well as the ability of NIRS to predict fruit shelf life and eating quality at harvest. [ABSTRACT FROM AUTHOR]

The decline in xylem flow during the late growth stage in most fruits may be due either to a decrease in the water potential gradient between the stem bearing the fruit and the fruit tissues or to a decrease in the hydraulic conductivity of xylem vessels, or both. In this study, we analysed changes in xylem flows to the mango Mangifera indica L. fruit during its development to identify the sources of variation by measuring changes in the water potential gradient and in the hydraulic properties of the fruit pedicel. The variations in xylem and transpiration flows were estimated at several stages of mango fruit development from the daily changes in the fresh mass of detached and girdled fruits on branches. The water potential gradient was estimated by monitoring the diurnal water potential in the stem and fruit. The hydraulic properties of the fruit pedicel were estimated using a flow meter. The results indicated that xylem flow increased in the early stages of fruit development and decreased in the late stage. Variations in xylem flow were related to the decrease in the hydraulic conductivity of xylem vessels but not to a decrease in the water potential gradient. The hydraulic conductivity of the fruit pedicel decreased during late growth due to embolism caused by a decrease in the fruit water potential. Further studies should establish the impact of the decrease in the hydraulic conductivity of the fruit pedicel on mango growth. [ABSTRACT FROM AUTHOR]