Genetic
diversity in sewan grass (Lasiurus sindicus Henr.) in
the
hot arid ecosystem of Thar Desert of Rajasthan, India
R.
Sharma, M. P. Rajora, R. Dadheech, R. K. Bhatt and R. K. Kalia*
Division of Plant
Improvement, Propagation and Pest Management
Central Arid Zone
Research Institute, Jodhpur, Rajasthan?342 003, India
*Corresponding
Author E-mail: rajwantkalia@yahoo.com
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Key
words
Arid ecosystem,
Desert grass,
Genetic diversity,
Sewan grass
Publication Data
Paper
received : 09.02.2016
Revised
received : 18.06.2016
Re-revised
received : 10.09.2016
Accepted : 09.11.2016
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Abstract
Aim: Sewan grass (Lasiurus
sindicus Henr.), considered as the ?King of Desert Grasses?, is a
dominant grass species of hot arid ecosystem of Great Indian Desert, covering
Western Rajasthan and parts of Pakistan. This grass is extremely drought
resistant and thrives even in areas receiving very low rainfall (100 to 150
mm) annually under extreme temperatures ranging from -3 to 50?C.
The present study was undertaken to analyze the extent of genetic variability
existing among the L. sindicus germplasm collected from Bikaner, Barmer and
Jaisalmer, the diversity rich districts of hyper-arid Rajasthan, using ISSR
and RAPD markers.
Methodology:
Twenty
seven genotypes of L. sindicus were collected from Jaisalmer (10
accessions), Barmer (9 accessions) and Bikaner (7 accessions) and 1 old
collection maintained at CAZRI, Jodhpur, Rajasthan was used in this study. A
total of 18 RAPD and 14 ISSR markers were screened of which 12 RAPD and 10
ISSR primers amplified distinct and scorable fragments. Data analysis was
performed using NTSYS-pc, SIMQUAL, Genalex 6.5 and POPGENE version 1.32
programs, and dendrograms were generated using unweighted pair group method
for arithmetic mean (UPGMA).
Results:
The
comparative analysis of data showed that RAPD markers were better than ISSR
with regard to polymorphism detection, as they detected 90% polymorphism in comparison
to 74% for ISSR markers. The values of average number of polymorphic
fragments per assay, polymorphism information content (PIC) and
discriminatory power (Dj) were more for RAPD (5.83, 0.222 and 0.78
respectively) than for ISSR (5.7, 0.138 and 0.605 respectively) markers. The
UPGMA clustering was not conspicuous under the influence of high within
region diversity, however, accessions collected from same region tended to
cluster together. Genetic similarity values obtained from Jaccard's coefficient
using combined data of both the marker systems were between 0.58 and 0.74.
Interpretation:
The
results indicated the existence of wide genetic variability within and among
regions in this species which can be used for germplasm conservation and improvement.
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