Advances in Molecular Cytogenetics: Potential for Crop Improvement

Abstract

Advances made over the last two decades in techniques and approaches used in molecular cytogenetics research and the results obtained so far have been briefly reviewed. These include the use of chromosome banding, fluorescence in situ hybridisation (FISH) and multicolour FISH (McFISH), genomic in situ hybridisation (GISH), flow cytometry, pulse field gel electrophoresis (PFGE), microdissection and microcloning, among others. These tools have been used both for identification of individual chromosomes and for physical localization of DNA sequences on individual chromosomes. Construction of genetic and physical maps of crop plants involving molecular markers as well as genes for agronomic traits has been discussed briefly. The use of these maps in comparative genomics, both at the macro- and micro-colinearity levels and for map based cloning has been briefly reviewed. The development and use of bacterial artificial chromosomes (BACs), yeast artificial chromosomes (YACs) and the future prospects of the development of plant artificial chromosomes (PACs) have also been discussed. The progress made in discovery of new genes through reverse genetics and functional genomics approach has also been presented.