[Epigenetic variation and its application in crop improvement].

Heritable variations in natural populations, including genetic variation and epigenetic variation, are the motivation for adaptation and evolution of plant species. Germplasm can be transferred stably from generation to generation by mitosis and/or meiosis without alteration in DNA sequence and protein expression. Here, two important sources of epigenetic variation, distant hybridization and polyploidy, and various biotic and abiotic stresses, are introduced. The application of epigenetic variation in crop improvement and its limitation, as well as optional solutions, are also summarized.