Influence of genome methylation of fig tree accessions on the natural nematode and rust incidence

Brazil is the largest fig producer in South America, but the Brazilian commercial fig tree cultivation is based on the planting of a single cultivar, ‘Roxo-de-Valinhos’, resulting in serious problems related to diseases. Since there are epigenetic variations in the plant-pathogen interaction, mainly through gene regulation, the aim of this study was to carry out the in vivo characterization of fig accessions through the analysis of the natural root-knot nematode and leaf rust incidence correlated to its epigenomic profile, in order to support conservation works and genetic improvement. Regarding the analysis of the presence of nematodes, it was observed that all plants were attacked by this pathogen, and the identification of Meloidogyne incognita as the root-knot nematode species was confirmed. However, the rust incidence and the global genomic methylation content where statistical different between evaluated accessions. The joint analysis of data showed that methylation and the leaf rust incidence, when observed in the same phenological phase of plants, are correlated, presenting evidences of the same factorial pressure loads in genotypes, with the premise of similar behavior in these genotypes. Biotic factors are also responsible for changes in the DNA methylation of plants, demonstrating a positive role in promoting plant defense.