International Journal of Agriculture, Environment & Biotechnology
Citation: IJAEB: 7 Special Issue : 439-450 July 2014
©2014 New Delhi Publishers. All rights reserved
Molecular Biology
Genetic diversity and molecular analysis among cotton
genotypes by EST-SSR markers.
Kundan K Mishra¹* and R S Fougat²
1 Department of Biotechnology, Genetics and Bioinformatics, N.V. Patel College of Pure and Applied Sciences,
Vallabh Vidyanagar 388 120, India.
2 Centre of Excellence in Biotechnology , B. A. College of Agriculture, Anand Agricultural University,
Anand –388 110, Gujarat, India.
*Corresponding author: Kundan K Mishra; kkmishra71075@gmail.com
Abstract
Objective of this research work is to utilize EST- SSR markers for fibre quality traits to generate genetic diversity between tetraploid
( Gossypium hirsutum ) and diploid ( Gossypium herbaceum and Gossypium arboreum) cotton species at molecular level. Twenty four (24)
genotypes of cotton and thirty five (35) EST SSR primers for different fibre quality traits (fibre length, Lint percentage, Boll weight and fibre
strength) were taken for this study. Almost all primers reveals amplification in both diploid and tetraploid cotton species which indicates
that flanking primer sequences are conserved in both genomes of cotton. Thirty one (31) EST SSR primers generate good and enormous
amplicon and produced a total of four hundred seventy eight (478) sharp, similar and variable bands in all genotypes. Average number of
bands amplified by each primer was 15.419. Statistical analysis for EST SSR data was conducted using software programme NTSYS pc
version 2.02e and GeneAlEx. The genetic distance (GD) among the all genotypes of cotton were also analyzed and it is ranged from 0.05 to
0.71 which indicates significant diversity between all the genotypes of both tetraploid and diploid cotton species. The average observed mean
heterozygosity was 0.60 and observed mean percentage of polymorphic loci was 60%.
Highlights
  • To study genetic diversity between tetraploid and diploid cotton species
  • Molecular analysis for phylogenetic relationship and fiber traits in both diploid and tetraploid cotton species
  • Identification and validation for EST-SSR markers in both diploid and tetraploid cotton species
  • Application of EST-SSR in Marker Assisted Selection(MAS) and cotton breeding
    Keywords: EST- SSR, Diploid, Tetraploid, Cotton, Fibre quality, Genetic Distance.
    The genus Gossypium commonly called cotton occurs
    Percival et al., 1999).The genome sizes are estimated
    naturally throughout tropical and subtropical regions and
    to be 880-Mb for Gossypium raimondii Ulbrich,-
    belongs to family Malvaceae and popularly called white
    1.75-Gb for Gossypium arboreum L, and ~2.5-Gb for
    gold, includes 50 species split across two ploidy levels, 45
    Gossypium hirsutum L.(Hendrix and Stewart,2005).
    species are diploid (2n=2x=26) and five are allotetraploid
    Among these 50 species four are mainly cultivated viz.
    (2n=2x=52) (Wendel 1989; Percival et al ; Wendal and
    Gossypium arboreum L.(n=x=13, A2) and Gossypium
    Cronn, 2003). There are three major lineages of diploid
    herbaceum L. (n=x=13 A1) are diploid while Gossypium
    species, corresponding to three continents: Australia (C,
    barbadense
    L.[n=2x=26,
    (AD)2]
    and
    Gossypium
    G, K genomes), the Americas (D genome), and Africa/
    hirsutum L.[n=2x=26, (AD)2] are teraploid (Kumria et
    Arabia (A, B, E, and F genomes) (Stewart et al., 1995;
    al. , 2003). Gossypium herbaceum L is limited to Gujrat