Genome-wide DNA methylation alterations of a wild potato species in natural experimental gardens

IBAÑEZ V.N.; BERLI F.; MASUELLI R.W.; MARFIL

Foz de Iguazú

Congreso; XI Congreso Internacional de Biología Molecular de Plantas (IPMB); 2015

SAG, SAIB, SAFV, REDBIO, BA PBL, SBBQ, SBG, SBPC

The wild potato species are adapted to diverse environments along the Andes range in the Americas. The more than 200 species described high phenotypic variations and little is known about the adaptation and plasticity response to environmental fluctuation. Three genotypes of the wild potato, Solanum kurtzianum were collected from populations along an elevational gradient at the Villavicencio Natural Reserve (VNR), Mendoza, Argentina. Biological replicates (clones) were in situ cultivated in the VNR in two experimental gardens at contrasting elevation (i.e. 1200 m vs. 2200 m a.s.l). The altitude gradient generates differences in ultraviolet-B radiation levels (10%) and mean temperature (35%). Morphological, productivity and biochemical characters measured in leaves and tubers showed significant differences, making the 1200 m plants distinguishable from the 2200 m plants. Those differences included increased area, width and thickness of terminal leaflet, reduced number of lateral and intercalar leaflets and shorter raquis, and increased levels in UV absorbing compounds in 2200 m respect to 1200 m plants. Plants cultivated at 2200 m a.s.l., produced fewer and smaller tubers than 1200 m plants, and in addition, the tubers collected from 2200 m plants sprouted, on average, 28 days earlier than tubers from 1200 m plants. Analyzing the epigenetic variability with the MSAP technique (Methylation Sensitive Amplified Polymorphism) it was observed that differential methylation patterns were established between clones of the same genotype according to the garden were they were cultivated. These results indicate that epigenetic variation plays an important role in the phenotypic variation and the distribution of this species.