Bol. Soc. Argent. Bot. 59 (1) 2024
introduction
species of Vachellia, and particularly, for V. aroma.
Then, this motivated us to the aims of this study
Vachellia aroma, synonym Acacia aroma (Gillies that were to develop, for the first time, SSR markers
ex Hook. & Arn.) Seigler & Ebinger (Seigler & specific for Vachellia aroma, an American species,
Ebinger, 2006), (Fabaceae, Caesalpinoideae) is a and test its amplification in a close related species.
tree that inhabits Central and South America, and the
Caribbean. In South America, the applications for
this tree are several. The wood has many uses, like materialS and methodS
charcoal and fuel, and more important, construction of
hard structures (del Valle Perea et al., 2007). A study
One silica gel-dried leaf sample of V. aroma
of the properties of its wood, yielded to a hard, dense belonging to one individual from Robles, Santiago
and durable one with the possibility of even more del Estero, Argentina (S 63°58’ 59.76”; W 28° 3’
potential uses (Pometti et al., 2009). Furthermore, 12.78”) was used in a simple sequence repeat (SSR)
its twigs and leaves are used in traditional medicine scan at the whole genome level. Total genomic
as infusion to treat gastritis, liver and stomach DNA was extracted with Mini Plant DNAeasy Kit
disorders, and as a digestive aid (Carrizo et al., 2005); (Quiagen) according to manufacturer manual. Then,
also, the leaves have antiseptic properties, useful in it was sequenced in a one-fourth run on a Roche
several affections of skin, throat, eyes and canker 454 GS FLX+ platform (454 Life Sciences, a Roche
(
&
Martínez Crovetto, 1981; Cialdella, 1984; Alonso Company, Branford, Connecticut, USA) by the
Desmarchelier, 2005; del Valle Perea et al., 2007). INDEAR, Rosario, Argentina, service.
As regards its cultivation, it adapts to silvopastoral In order to identify microsatellite sequences
production systems. Their fruits and leaves serve as in the contigs obtained, we used the software
forage for goats, sheep and cattle (Demaio et al., 2002; MSATCOMMANDER v. 0.8.2 (Faircloth, 2008).
del Valle Perea et al., 2007), but the size of the thorns We used the option Design primer, in which the
turn the access to the higher branches very difficult. In software searches for microsatellite repeats and
this line, several years ago, we started an improvement identifies possible primer annealing sites in one step.
program of controlled crossings aiming to reduce Primer3 (Rozen & Skaletsky, 2000) is implemented in
the size of the thorns in the Estación Experimental MSATCOMMANDER for primer design according
Fernández, Santiago del Estero, Argentina.
to the following criteria: amplification products
The microsatellites or Simple Sequence Repeat within the size range of 100-500 bp, optimal melting
(
SSR) are short sequences, from two to six nucleotides, temperature (range 57-62 ºC), optimal GC content of
tandem repeated that can vary in number and sequence 50%, possession of at least 1-bp GC clamp, low levels
across the different individuals. The main advantage of self- or pair-complementary, and maximum end
that these markers offer for the genome analysis stability (D G) of 8.0 (Faircloth, 2008).
is their abundance and dispersion in the DNA.
Amplification through PCR was performed on
Its value consists in their multialellic nature and individual loci in 50µl reactions containing 10/30
codominat inheritance, allowing the detection of ng DNA, 0.6 mM each primer, 0.2 mM dNTPs, 0.3
several variants in the population. The SSR can be U Taq DNA polymerase (Invitrogen, Buenos Aires,
found in all the eukaryote organisms, they are highly Argentina), and 1.5 mM MgCl . A T21 IVEMA
2
polymorphic, and, although they are genome-specific, thermal cycler (IVEMA, Buenos Aires, Argentina)
they could be transferred across species, according was used for amplifications, where the cycling
to the phylogenetic distance between them and the profile was initial denaturation at 94 ºC for 5 min;
loci conservation (Ferreira, 2003). Therefore, these followed by 40 cycles at 94 ºC for 45s denaturation,
markers have become a very valuable tool for the primer-specific annealing temperature (53-58 ºC;
genetic mapping of species, diversity analyses, studies see Table 1) for 45 s, extension at 72 ºC for 45 s;
of gene flow and differentiation between populations, and a final extension at 72 ºC for 10 min. PCR
and genetic improvement and breeding (Contreras et products were run in a 6% (w/v) polyacrylamide gel
al., 2020).
containing 5 M urea in 1% TBE buffer (89 mM Tris,
There are currently, to our knowledge, no 89 mM boric acid, 2 mM EDTA, pH 8) with a 10-bp
microsatellite markers available for any American DNA Ladder (Invitrogen) size marker. Gels were
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