Phenotypic and genotypic characterization of ‘Chinotto di Savona’ Citrus accession

For a long time \u2018Chinotto di Savona\u2019, a Citrus tree cultivated in Liguria region (northern Italy), has been considered a variety of Citrus myrtifolia (known with the Italian name \u2018chinotto\u2019). Nevertheless, molecular analysis to address its true genetic origin has been not performed yet. Fruits of \u2018Chinotto di Savona\u2019 are highly appreciated and often preferred to common chinotto for its superior organoleptic characteristics by food and beverage industries. This work reports a first morphological and genetic characterization of \u2018Chinotto di Savona\u2019 aiming at inferring its origin and main pomological traits. The main phenotypic characteristics of this Citrus accession were also evaluated and compared with those of the \u2018common\u2019 chinotto, considering leaves, shoots, fruits and seed morphology and juice composition. In addition, the colour evolution of fruit flavedo was monitored by reflectance spectroscopy. Molecular analyses were performed using SSR, AFLP and RNA-seq-derived markers, providing tools to discriminate \u2018Chinotto di Savona\u2019 from C. myrtifolia. A cytogenetic analysis was performed to assess ploidy of the Chinotto accessions. Findings confirm the genetic similarity of \u2018Chinotto di Savona\u2019 and C. myrtifolia, supporting the running hypothesis of their origin from somatic mutations of sour orange. Further analysis will be needed in order to fully understand whether they are independent somatic mutations of sour orange or if they originated from each other