Vineyard environments influence Malbec grapevine phenotypic traits and
DNA methylation patterns in a clone-dependent way
Abstract
Clonal selection and vegetative propagation determine low genetic
variability in grapevine cultivars, although it is common to observe
diverse phenotypes. Environmental signals may induce epigenetic changes
altering gene expression and phenotype. The range of phenotypes that a
genotype expresses in different environments is known as phenotypic
plasticity. DNA methylation is the most studied epigenetic mechanism,
but only few works evaluated this novel source of variability in
grapevines. In the present study, we analyzed the effects on phenotypic
traits and epigenome of three Vitis vinifera cv. Malbec clones
cultivated in two contrasting vineyards of Mendoza, Argentina. Anonymous
genome regions were analyzed using Methylation-Sensitive Amplified
Polymorphism (MSAP) markers. Clone-dependent phenotypic and epigenetic
variability between vineyards were found. The clone that presented the
clearer MSAP differentiation between vineyards was selected and analyzed
through Reduced Representation Bisulfite Sequencing. Twenty-nine
differentially methylated regions (DMRs) between vineyards were
identified and associated to genes and/or promoters. We discuss about a
group of genes related to hormones homeostasis and sensing that could
provide a hint of the epigenetic role in the determination of the
different phenotypes observed between vineyards and conclude that DNA
methylation has an important role in the phenotypic plasticity and that
epigenetic modulation is clone-dependent.