Molecular cytogenetics for identification of alien chromosomes and chromosome segments

Abstract

The transfer of alien genes into the genetic background of cultivated crop varieties is becoming an important aspect of modern crop improvement programmes. Introgressive hybridization has widened the genetic base ofthe present day crop cultivars. This chapter depicts the necessity of molecular cytogenetic tools for identification and characterization of the introgressed alien chromosome segments or genes. There are several instances where different molecular cytogenetics tools including in situ hybridization, FISH, GISH and high resolution mapping have been successfully used to detect alien chromosomes or chromosome segments across different crop speciesand such alien introgressions have been successful in increasing the economic value of the crop. This chapter discusses many such examples and emphasizes upon the increasing role of molecular cytogenetics in alien gene transfers.