Genomic instability in Solanum tuberosum x Solanum kurtzianum interspecific hybrids

C. F. MARFIL, R. W. MASUELLI, J. DAVISON AND L. COMAI

GENOME

Año: 2005

0831-2796

The use of interspecific crosses in breeding is an important strategy to improve the genetic base of the modern cultivated potato, Solanum tuberosum L. Usually, interspecific Solanum hybrids have been morphologically and cytologically characterized. However, little is known about the genomic changes that may occur in the hybrid nucleus due to the combination of genomes of different origin. No cytological abnormalities were observed in the hybrids; however, we found DNA methylation changes that could be the cause of the observed genomic instabilities. Of 277 MSAP fragments analyzed, 14% showed methylation patterns that differed between the parental species and the hybrids. We also observed frequent methylation changes in the BC1 progeny. Variation patterns among F1 and BC1 plants suggest that some methylation changes occurred at random. The changes observed may have implications for potato breeding as an additional source of variability.