Ravi Prakash Shukla*
Cotton (Gossypium spp.) is major cash crop of India and this country is the second largest cotton producer in the world after China. G. hirsutum and G. Barbadense two tetraploid species are majorly cultivated. In cotton many traits like fiber quality, drought tolerance, ball weight, ball number and yield are controlled by polygene or Quantitative trait locus. The development of meaningful molecular markers from different resources of cotton in the mapping population background to accelerate the QTL identification using different arithmetical programme is intense for QTL mapping. Current review provides an update on comparative studies and application of different molecular markers (RFLP, AFLP, RAPD, SSR, EST-SSR, SNP etc.) in cotton breeding programme.