303
to the Province of San Luis (Central Argentina). It has been suggested that the
Caldén have not suffered marked genetic erosion yet, and a great phenotypic variability has been reported. As for the rest of the species of Prosopis genus, swarms
of hybrids have been observed in zones with sympatry between P. caldenia and
P. flexuosa. Absence of barriers of reproductive isolation and sympatry have facilitated hybridization and introgression in the genus Prosopis (e.g. Palacios and Bravo
1981; Naranjo et al. 1984; Hunziker et al. 1986) and have contributed to the morphological and genetic variability observed in pure populations of Caldén.
High percentage of polymorphism in P. caldenia was reported by means of microsatellites transferred from other Prosopis species (Sherry et al. 2011; Bessega
et al. 2013). The pioneer study by Pérez Díaz (2014) allowed the genetic characterization of two Caldén populations through different molecular markers. As a result,
SRR and ISSR were more valuable to detect polymorphic loci among individuals of
P. caldenia than those obtained by RAPD. According to the general expectation for
the Algarobia section (Bessega et al. 2005), diversity in P. caldenia was high
(He = 0.54) (Velasco 2018). Nei’s genetic distances of P. caldenia conspecific populations (0.080) are similar to those obtained among Prosopis nigra populations
(0.096) and Prosopis ruscifolia (0.081) (Ferreyra 2000).
Currently, there is only one publication referred to the genetic diversity of
G. sarmientoi (Camps et al. 2018). In this study the authors characterized the genetic
diversity across almost the entire geographical range of the species (sampling natural populations from Argentina, Bolivia and Paraguay) using two non-coding fragments of chloroplast DNA (cpDNA). The retrieved haplotype network revealed
three distinct phylogroups which overlapped geographically. At the species level,
haplotype diversity was h = 0.685 (SD: 0.039), and nucleotide diversity was
π = 0.0012 (SD: 0.0007). The highest value of haplotype diversity per population
was h = 0.867 (SD: 0.1291), while the lowest value was h = 0.333 (SD: 0.2152). For
the nucleotide diversity, values varied between π = 0.000220 (SD: 0.000290) and
π = 0.002332 (SD: 0.001591). The highest levels of genetic diversity were found in
the northwest, centre and southeast areas of the distribution (see Fig. 11.7). Exclusive
haplotypes were found throughout the spatial range, although they were more frequent in sites located at the edge of the geographical distribution.
11.3 Mating System
The information on population structure and mating system is paramount for developing strategies for rational use and conservation programmes of native species as
they contribute to define the breeding units in the wild.
For Acacia species the experimental evidence indicates that most are predominantly outcrossers, sometimes presenting self-incompatibility systems (Kenrick and
Knox 1985; Sedgley et al. 1992). In the study of mating system of four populations
of A. caven using isozymes (Pometti et al. 2011), the estimate for the multilocus
11 Species Without Current Breeding Relevance But High Economic Value: Acaci
to the Province of San Luis (Central Argentina). It has been suggested that the
Caldén have not suffered marked genetic erosion yet, and a great phenotypic variability has been reported. As for the rest of the species of Prosopis genus, swarms
of hybrids have been observed in zones with sympatry between P. caldenia and
P. flexuosa. Absence of barriers of reproductive isolation and sympatry have facilitated hybridization and introgression in the genus Prosopis (e.g. Palacios and Bravo
1981; Naranjo et al. 1984; Hunziker et al. 1986) and have contributed to the morphological and genetic variability observed in pure populations of Caldén.
High percentage of polymorphism in P. caldenia was reported by means of microsatellites transferred from other Prosopis species (Sherry et al. 2011; Bessega
et al. 2013). The pioneer study by Pérez Díaz (2014) allowed the genetic characterization of two Caldén populations through different molecular markers. As a result,
SRR and ISSR were more valuable to detect polymorphic loci among individuals of
P. caldenia than those obtained by RAPD. According to the general expectation for
the Algarobia section (Bessega et al. 2005), diversity in P. caldenia was high
(He = 0.54) (Velasco 2018). Nei’s genetic distances of P. caldenia conspecific populations (0.080) are similar to those obtained among Prosopis nigra populations
(0.096) and Prosopis ruscifolia (0.081) (Ferreyra 2000).
Currently, there is only one publication referred to the genetic diversity of
G. sarmientoi (Camps et al. 2018). In this study the authors characterized the genetic
diversity across almost the entire geographical range of the species (sampling natural populations from Argentina, Bolivia and Paraguay) using two non-coding fragments of chloroplast DNA (cpDNA). The retrieved haplotype network revealed
three distinct phylogroups which overlapped geographically. At the species level,
haplotype diversity was h = 0.685 (SD: 0.039), and nucleotide diversity was
π = 0.0012 (SD: 0.0007). The highest value of haplotype diversity per population
was h = 0.867 (SD: 0.1291), while the lowest value was h = 0.333 (SD: 0.2152). For
the nucleotide diversity, values varied between π = 0.000220 (SD: 0.000290) and
π = 0.002332 (SD: 0.001591). The highest levels of genetic diversity were found in
the northwest, centre and southeast areas of the distribution (see Fig. 11.7). Exclusive
haplotypes were found throughout the spatial range, although they were more frequent in sites located at the edge of the geographical distribution.
11.3 Mating System
The information on population structure and mating system is paramount for developing strategies for rational use and conservation programmes of native species as
they contribute to define the breeding units in the wild.
For Acacia species the experimental evidence indicates that most are predominantly outcrossers, sometimes presenting self-incompatibility systems (Kenrick and
Knox 1985; Sedgley et al. 1992). In the study of mating system of four populations
of A. caven using isozymes (Pometti et al. 2011), the estimate for the multilocus
11 Species Without Current Breeding Relevance But High Economic Value: Acaci