Mishra and Fougat
Table 1. List of genotypes
Sr.
Gossypium herbaceum Sr. No.
Gossypium arboreum
Sr. No.
Gossypium hirsutum
No.
1.
Digvijay
12.
824
19.
G. cot 12
2.
Gvhv133
13.
CINA 329
20.
G. cot H4
3.
Dhumad
14.
CINA318
21.
G. cot 16
4.
Gvhv235
15.
Jawahar Tapti
22.
G. cot H10
5.
Gvhv544
16.
G-27
23.
G cot 8
6.
V-797
17.
CINA333
24.
G. cot 20
7.
G. cot 13
18.
DLSA17
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----
8.
G.cot 21
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---
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9.
G. cot 23
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and Karnataka. Gossypium hirsutum L and Gossypium
studies (Liu et al ., 2000b; Grutierrez et al., 2002)
arboreum L are grown in all the major cotton growing
and are useful for a variety of applications in plant
states of India. Gujrat has been a major cotton producing
genetics and breeding because of their reproducibility,
state for last many years. In term of area, Gujrat ranked
multiallelic nature, codominant, relative abundance and
2 nd next to Maharastra and contributes about ~37.5% of
good genomic coverage (Powel et al ., 1996). SSR are
the national cotton production from~ 26.5 area of the
easy to use and analyze (Morgante and Olivieri 1993).
country.
The variation among microsatellite is thought to be due
Cotton is the world’s leading textile fiber crop and it
to the slippage of DNA polymerase during replication
is also source of secondary products such as oil, live-
or unequal crossing over, resulting in differences in the
stock feed (cotton seed cake) and cellulose and play
copy number of the actual nucleotide sequences (Yu
an important role in global economy. In recent years,
et al.,1999). Polymorphism among individuals arises
improvement in the quality of cotton fiber has been
from changes in the number of the repeats. In the other
extremely important because of changes in spinning
words, these markers meet most of the requirements
technology (Shen et al .,2005). Enhanced cotton resources
for ideal markers for assessing gene flow. Tracking of
are needed to facilitate the improvement of this important
microsatellite markers requires specifically designed
crop. Therefore, an important area of cotton genomics is
primers for conserved flanking region of repeats and
germplasm characterization and utilization. Analysis of
PCR amplification of this region. The availability and
genetic diversity and relatedness between species and
abundance of microsatellite markers throughout the cotton
among genotypes is useful in plant breeding programs
genome coupled with the fact that they are polymorphic,
because it provides a tool for accurate organization
co-dominant and are based on polymerase chain reaction
of germplasm and efficient parental selection. With
(PCR) make them particularly useful in genetic diversity
advancement in molecular marker technology, marker-
studies of cotton (Reddy et al ,2001), with in excess of
assisted selection (MAS) combined with conventional
1000 microsatellite primers having already been isolated
breeding has been one way in which fiber quality can
from cotton DNA genomic libraries (Nguyen et al .,), for
improved
molecular studies of the genetic diversity (Brubaker and
Wendel. 1994; Tatineni et al ., 1996; Iqbql et al ., 1997).
Simple sequence repeat (SSR) markers (microsatellite)
However, more work need to be carried out and the
are tandemly repeated DNA motifs (1-6bp long) which
purpose of work is to investigate and compare the genetic
may vary in the number of repeats at given locus, have
diversity of cotton plants cultivated in several country
been sucessfully employed in many genetic diversity
of Asia with the specific objectives of estimating the
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