Polyploidy and Plant Breeding

Abstract

Polyploidy in plant species is derived mostly from meiotic nonreduction through 2n gametes, which occur due to mutants affecting microsporogenesis and megasporogenesis. The ensuing highly plastic genome structure led to its success in flowering plants. Integrative genomics research giving unique perspective on the domestication of amphidiploid species may facilitate the manipulation of useful variation in plant breeding. Endosperm dosage influenced the speciation of many polyploid species and together with ploidy manipulations—scaling up and down chromosome numbers of a species within a polyploid series—allows the transfer of desired genes from a diploid species into a polyploid species. The tetraploid potato is the model species for the genetic enhancement of vegetatively propagated polysomic polyploid crops, while triploid banana/plantain offers an example of an evolutionary improvement approach enhanced by innovative knowledge-led methods for introducing additional genetic variation. Biotechnology assists in interspecific hybridization and ploidy manipulation, and through diagnostics, pathogen elimination, genetic engineering, and marker-aided selection (MAS).