Phenotypic and epigenetic variation induced in newly synthesized allopolyploids and autopolyploids of potato

MARFIL, CARLOS F.; MARFIL, CARLOS F.; DUARTE, PAOLA F.; DUARTE, PAOLA F.; MASUELLI, RICARDO W.; MASUELLI, RICARDO W.

SCIENTIA HORTICULTURAE

ELSEVIER SCIENCE BV

Año: 2018 vol. 234 p. 101 - 109

0304-4238

Polyploidy is one of the most important events in plant evolution: the evidence suggests that more than 70% ofthe angiosperms underwent some event of genomic duplication during their diversification. In potato, the thirdmore important crop worldwide, the effects of autopolyploidization at morphological, physiological and molecularlevels have been explored and no evident phenotypic superiority of polyploid lines respect to the parentaldiploid lines has been found. On the other hand, the consequences of allopolyploidization have not been analysedso far in potato from a molecular point of view. In this work we study the variability induced by wholegenome duplication in potato auto and allotetraploids obtained by chromosomal duplication of a S. kurtzianumgenotype (autopolyploid model) and by chromosomal duplication of a diploid interspecific hybrid between S.tuberosum and S. kurtzianum (allopolyploid model). Polyploid lines in both models showed a tendency to increasethe vigor in phenotypic characters compared with diploid parent they derived from. AFLP analysis showed nopolymorphism between parental diploid and derived polyploids lines. However, there were DNA methylationchanges between diploids and polyploids, indicating that polyploidization alters the epigenetic patterns in potato.It is possible that the superiority of the tetraploid can be explained as a heterotic response dependent on thepresence of heterozygous loci and epistatic interactions inducing alterations in the gene regulation of thepolyploid genomes.