Abstract

Varieties of Japanese plum (Prunus salicina) are diverse in terms of skin and flesh phenotypes. Previous studies have described different patterns of flavonoids accumulation associated with fruit phenotypes. In order to identify possible points of regulation associated with the color character, skin and flesh tissues in four contrasting varieties and considering four stages of fruit development (from pit hardening to full color stage) were characterized. Accumulation pattern of total phenols, tannins and anthocyanins were analyzed. Moreover, partial sequences from structural genes of the flavonoid pathway were isolated and specific primers were designed for each gene. Subsequently, the transcriptional expression analysis done by qPCR allowed us the identification of expression patterns associated to different developmental stages and tissues for each of the analyzed varieties. The structural genes CHS, CHI, F3H y DFR showed consistent expression patterns as described previously, however, different expression patterns were observed in ANS/LDOX and UFGT genes. These genes were expressed in the presence of anthocyanins and strongly repressed in absence of it on the tissues, opening the hypothesis of a new regulatory mechanism not described for the Prunus genera.