Comparative Transcriptome Profiling in a Segregating Peach Population with Contrasting Juiciness Phenotypes

Cold
storage of fruit is one of the methods most commonly employed
to extend the postharvest lifespan of peaches (Prunus persica (L.) Batsch). However, fruit quality in this species is affected
negatively by mealiness, a physiological disorder triggered by chilling
injury after long periods of exposure to low temperatures during storage
and manifested mainly as a lack of juiciness, which ultimately modifies
the organoleptic properties of peach fruit. The aim of this study
was to identify molecular components and metabolic processes underlying
mealiness in susceptible and nonsusceptible segregants. Transcriptome
and qRT-PCR profiling were applied to individuals with contrasting
juiciness phenotypes in a segregating F2 population. Our
results suggest that mealiness is a multiscale phenomenon, because
juicy and mealy fruit display distinctive reprogramming processes
affecting translational machinery and lipid, sugar, and oxidative
metabolism. The candidate genes identified may be useful tools for
further crop improvement.