Harvest maturity modulates the synchronization between exocarp color change and mesocarp softening in avocado cv. Hass: A multiomics perspective

Abstract

[EN] Avocado cv. H<acute accent>ass<acute accent>is a crop of worldwide importance and demand. Fruit mesocarp firmness and exocarp color are essential parameters determining <acute accent>Hass<acute accent> avocado ripening and consumer acceptability. Exocarp color de-synchronization with softening is a relevant recurrent problem for the avocado supply chain, particularly during marketing. This research aimed to investigate how harvest maturity influences this quality issue by metabolomic, transcriptomic, and hormonal differences in avocado fruit collected at different harvest maturities. In addition, early potential biomarkers of exocarp color-mesocarp firmness de-synchronized fruit at harvest are proposed. Integration of multi-omics data revealed an overactivation of the phenylpropanoid pathway in early harvested fruits, particularly at key branches associated with the biosynthesis of lignin, quercetin, and epicatechins derivatives-metabolic processes that are linked to a higher incidence of color-softening desynchronization. In contrast, late harvest fruits, less susceptible to this disorder, exhibited enhanced expression of genes involved in the anthocyanin biosynthesis pathway compared to early harvest samples. We propose quinic acid, beta-sitosterol, mannoheptulose as early harvest biomarkers and indole acetic acid (IAA), xylitol and arabitol for late harvest biomarkers. These findings suggest that in late harvest fruits, the colour transition process is already underway at time of harvest, promoting a more synchronized progression between exocarp coloration and mesocarp softening.