Introgression of Genes by Wide Hybridization: a Crop Improvement Approach

Introgression is the movement of genes or gene flow from one species into the gene pool. wide hybridisation breaks the species barrier for gene transfer and makes it possible to transfer the genome of one species to other, which results alteration in genotypes and phenotypes of the progeny. The main objective of wide hybridisation is to transfer desirable genes, to create genetic variability when it lost due to domestication and creation of novel crop species.it is not always successful, where development of young zygote may be arrested by hybrid breakdown, hybrid sterility and hybrid non viability. The F1 plants obtained from wide hybridization showed sterile and semi sterile due to abortion of male and female gametes. The pre-fertilisation and post-fertilisation factors affects the fruit set in chilli and it showed highly significant positive correlation with pollen germination and pollen tube growth for transferring fruit rot resistance to C. annum. Chromosomal manipulation in wide hybrids based on their chromosome behaviour and constitutions are chromosome elimination, chromosome doubling with production of unreduced gametes and homeologus pairing with translocated segments. Transfer of auxinic herbicide resistance from wild mustard into radish was achieved through distant hybridization with embryo rescue. Successful interspecific hybridization can be achieved through wide hybridization with embryo rescue, through study of cytological events in meiotic division and identifying genes controlling homologous pairing between wild and cultivated species.