Identification of biomarkers associated to ‘Gala’ apples ripening and postharvest quality

Abstract

Apple is, sociocultural and economically, on of the most important species in the world, and stands out for its high storage potential. However, the monitoring of factors that could result in fruit quality modifications during postharvest is essential to ensure the acceptability and for the development of new storage technologies in order to increase fruit shelf life. Approaches focused on molecular biology, such as RT-qPCR have been used to better understand the mechanisms involved in fruit development and maturation. In this study the use of RT-qPCR to monitoring apple quality during ripening and development in different postharvest conditions such as room temperature, cold storage with or without control of atmosphere and the 1-methylcyclopropene usage were proposed. The potential of genes involved in ethylene biosynthesis and response, cell wall modification and degradation, sugar and aroma metabolisms for employment as biomarkers of fruit development and quality were evaluated. Thus MdEXP4 is highlighted as biomarker for development and MdACO1, MdPG1, MdAF1, MdAF3 and MdAAT2 as potential biomarkers for ripening. MdACO1 and MdPG1 appear as suitable markers for quality, conservation technologies and storage time in apples. This work suggests that the study of gene expression by RT-qPCR may be an alternative for a better fruit characterization during the development and postharvest period.