Distant Hybridization: A Tool for Interspecifi c Manipulation of Chromosomes

A. Pratap and J. Kumar (eds.), Alien Gene Transfer in Crop Plants, Volume 1: Innovations, Methods and Risk Assessment, DOI 10.1007/978-1-4614-8585-8_2, © Springer Science+Business Media New York 2014 Abstract Wide or distant hybridization has been widely used as an important tool of chromosome manipulation for crop improvement. The chromosome behaviors in F 1 hybrids provide us with the essential genetic basis for chromosome manipulation. The induction of homoeologous pairing in F 1 hybrid plants followed by the incorporation of a single-chromosome fragment from an alien or a wild species into an existing crop species by translocating chromosomes has been used in the production of translocation lines. Most efforts to transfer a benefi cial trait from wild plants into crops so far have bridged the species gap via alien chromosome translocation lines. Chromosome doubling in somatic cells or gametes of F 1 hybrids followed by the incorporation of all alien chromosomes has been used in the production of amphidiploids. Amphidiploidy can be used for a bridge to move a single chromosome from one species to another or for the development of new crops. Chromosome elimination of a uniparental genome during the development of F 1 hybrid embryos has been used in the production of haploids. Haploids are very useful in double-haploid breeding of a true-breeding crop such as wheat and rice since this method can quickly replace genetic recombination while enhancing breeding effi ciency or facilitating genetic analysis.