Methyl jasmonate as a tool to improve anthocyanins on grapes grown on subtropical climate

Vitis labrusca L. grapes are largely cultivated in Brazil, but the tropical climate affect negatively the phenols content, especially anthocyanins. In the future, due to the global climate changes, such phenomenon could expand in more regions. Therefore, many researches focus on increasing grape phenols content, and methyl jasmonate (MeJa) treatment could be a good alternative. Since studies on Vitis vinifera L. grapes gave promising results, the aim of this study was to evaluate anthocyanin changes caused by the MeJa pre-harvest application on two Vitis labrusca L. cultivars grape, both grown in two Brazilian regions. Isabel Precoce and Concord grapes cultivated under subtropical climate on south and southeast of Brazil, received MeJa pre-harvest treatment. Grape metabolites were extracted and analyzed with a MS based metabolomics protocol by UPLC-HRMS-QTOF. Unsupervised data analysis reveals clear separation between the two regions and the two cultivars, while supervised data analysis revealed biomarkers between MeJa and control group. Among the varieties, Concord grapes were more responsive to the treatment, while Isabel Precoce cultivated on the south was the least responsive one. We annotated 35 anthocyanins, such cyanidin, peonidin, delphinidin, malvidin and petunidin in the caffeoyl, acetyl and p-coumaroyl mono and diglucoside derivatives. We observed, that MeJa promoted higher amounts of anthocyanins 3’ hydroxylated, acetylated and coumarylated derivatives forms, with exception of Isabel Precoce grapes cultivated on southeast region. Our results suggested that MeJa could be used as elicitor to secondary metabolism in grapes grown even under subtropical climate, affecting anthocyanin biosynthesis