TITLE:
Genetic Diversity Estimates of Santalum album L. through Microsatellite Markers: Implications on Conservation
AUTHORS:
Tanzeem Fatima, Ashutosh Srivastava, Vageeshbabu S. Hanur, P. V. Somashekar, M. Srinivasa Rao
KEYWORDS:
Sandalwood, Genetic Diversity, Alleles, Microsatellite Markers, PCA
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.10 No.3,
March
21,
2019
ABSTRACT: Sandalwood (Santalum
album L.) is the second most expensive wood in the world. There are
approximately 16 species of sandalwood (S.
album, S. spicatum, S. austrocaledonicum, S. yasi, S. lanceolatum, S. ellipticum, S. macgregorii, S. insulare) occurring naturally
throughout Australia, India, Indonesia, Papua New Guinea and the islands of the
South Pacific. In India, S. album is found all over the country,
with over 90% of the area in Karnataka, Tamil Nadu, Kerala, Andhra Pradesh and
Telangana state. It is highly economic tropical tree species because of its
scented heartwood and heartwood oil. Several causes have been attributed to the
depletion of sandalwood population mainly amongst which theft is causing
negative effect on the quality of species by constant removal of superior
clones. The aim of this study was to determine the genetic diversity of S. album. For this, 177 genotypes of S. album from 14 populations of three
states (Karnataka, Telangana state and Kerala) in southern India were selected.
The genetic diversity and genetic structure were characterized through 25 SSR
markers developed by cross amplification of different species of Sandalwood.
Under this study, following genetic diversity parameters were
estimated at individual level and population level; Number of alleles
(Na) 9.107, Effective number of alleles (Ne) 7.56, Observed heterozygosity (Ho)
0.187, Expected heterozygosity (He) 0.861, Shannon information index (I) 2.03,
F statistics 0.89, Polymorphic information content (PIC) 0.87 and Gene flow
(Nm) 4.98. The estimates of gene flow among the populations of Kodada Telangana
(Nm = 15.109); IWST Karnataka (Nm = 13.62) than across other geographical
populations (Nm = 9.40). Analysis of molecular variance (AMOVA) revealed that
3% of the total variation was due to differences among populations and 97% due
to differences within the populations. The genetic differentiation among
populations (FST) 0.012 at p results showed the combined variation 82.2% of these
markers. This study highlights the knowledge of genetic variation in sandalwood
across the herd population of sandalwood in India. The highest range of
polymorphism was detected with SSR markers developed from Osyris lanceolata compared to Santalum. austrocaledonicum, Santalum. insulare and Santalum. spicatum. This study would help in
conservation of the Sandalwood populations
with high profile of genetic diversity and selection of clones for
genetic improvement program.