Development of functional molecular markers for crop plants
Rajesh Singh1, RK Singh2
1Genetics and Plant Breeding, IAS, BHU Varanasi-221005
2Visiting Scientist, Plant Genome Mapping Laboratory, 111 River Bend Road, University of Georgia, Athens, GA (USA)
Received: 14 March 2015 Revised Accepted: 28 April 2015
ABSTRACT
Molecular markers offer numerous advantages over conventional phenotype based alternatives as they are stable and detectable in all tissues regardless of growth, differentiation, development, or defense status of the cell are not confounded by the environment, pleiotropic and epistatic effects. Functional markers (FMs) are a good “translator” of gains from emerging technologies into improved crop cultivars. FMs are derived from polymorphic sites within genes causally involved in phenotypic trait variation. Once genetic effects have been assigned to functional sequence motifs, FMs derived from such motifs are used for fixation of gene alleles in a number of genetic backgrounds without additional calibration. FM development requires (1) functionally characterised genes, (2) allele sequences from such genes, (3) identification of polymorphic, functional motifs affecting plant phenotype within these genes and (4) validation of associations between DNA polymorphisms and trait variation.
Key Words: DNA Markers, Functional Markers, Polymorphism, RAPD, RFLP, SSR, SNPs