Brown rot, caused by Monilinia spp., provokes pre- and post-harvest damage in peach (Prunus persica (L.) Batsch), which causes an economic impact in the industry. With a view to breeding for increased tolerance to this disease, a screening test based upon artificial fruit inoculation was validated on several parental lines of a peach breeding program during the two-period harvest. In addition, cultivars with different total phenolic contents were included in the two-year study. All physicochemical fruit traits recorded at harvest showed differences among all cultivars. The antioxidant compound content determined using spectrophotometry (to measure ascorbic acid and antioxidant capacity) and UPLC-MS (to measure and identify phenolic compounds) also revealed important differences among all genotypes. The rate of brown rot lesion following fruit inoculation varied widely among cultivars, and it was possible to discriminate between highly and less susceptible cultivars. Cultivars with minimal development of damage were identified as germplasm with the desirable allele combination to increase brown rot tolerance in peach breeding programs. Finally, Pearson’s correlation coefficients (r) between pairs of variables were calculated, searching for any biochemical candidate conferring tolerance. The correlation of phytopathological traits with the antioxidant composition, concerning contents of ascorbic, neochlorogenic, and chlorogenic acids and total polyphenols in fruit, is discussed.

a.Identificación de genes relacionados con la tolerancia a la sequía en 41 variedades de quinua (Chenopodium quinoa Willd) Identification of genes related to drought tolerance in 41 varieties of quinoa (Chenopodium quinoa Willd) Resumen El objetivo de la investigación fue identificar los genes relacionados con la tolerancia a la sequía en la quinua. Para ello, se evaluaron 41 variedades de Chenopodium quinoa Willd con seis repeticiones; en la etapa de floración, se seleccionaron al azar tres macetas/material, de cada variedad, para ser inducidas a sequía total por dos semanas, reanudándose el riego después de ese periodo, las otras tres fueron el control. A partir del día 27 después de la siembra, se midió el nivel de clorofila y se clasificó como tolerante o susceptible a la sequía, en función de su índice de contenido clorofila (ICC). Para la identificación de genes se tomaron muestras de hoja de tres variedades (Red head, Salcedo INIA y Kankolla 1). La Extracción del ARN se realizó usando el reactivo reagent® TRI y para el secuenciamiento de transcriptomas se utilizó la plataforma de Ilumina. Se identificaron 26 genes en las tres variedades de quinua, pero en las variedades tolerantes a la sequía; tres de ellos son regulados al alza ante la exposición a la sequía y cinco genes (AUR62037809, AUR62000271, AUR62037807, AUR62042825 AUR62009791) tienen un cambio en su patrón de expresión como consecuencia de la exposición a la sequía. Palabras clave: quinua; RNA-Seq; transcriptoma; sequía; Clonación al Azar. AbstractThe objective of the research was to identify the genes related to drought tolerance in quinoa. For this, 41 varieties of Chenopodium quinoa Willd were evaluated with six repetitions; in the flowering stage, three pots/material, of each variety, were randomly selected to be induced to total drought for two weeks, resuming irrigation after that period, the other three were the control. From day 27 after sowing, the chlorophyll level was measured and classified as tolerant or susceptible to drought, based on its chlorophyll content index (CCI). For the identification of genes, leaf samples of three varieties were taken (Red head, Salcedo INIA and Kankolla 1). RNA Extraction was performed using reagent® TRI reagent and for the transcriptome sequencing the Ilumina platform was used. 26 genes were identified in the three varieties of quinoa, but in the drought tolerant varieties; three of them are regulated upwards when exposed to drought and five genes (AUR62037809, AUR62000271, AUR62037807, AUR62042825 AUR62009791) have a change in their pattern of expression as a result of drought exposure.

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