Genetic structure in fragmented populations of Solanum lycocarpum A. St.-Hil. with distinct anthropogenic histories in a Cerrado region of Brazil

Abstract

ABSTRACT. Solanum lycocarpum is a woody tree widely distributed in the Cerrado that reaches high population densities in disturbed environments. We examined the genetic diversity and population differentiation of six S. lycocarpum populations with different degrees of human disturbance in order to determine if they are negatively affected by anthropogenic activity. Three populations located in southern and three located in southeastern regions of Goiás State, Central Brazil, were genotyped with five microsatellite markers. The population located in a protected area had higher number of alleles (26) 2674-2682 (2012) Negative effect of the ecosystem fragmentation 2675 alleles). It indicates that extensive and continuous areas of preserved native vegetation contribute positively to the conservation of genetic diversity, even with S. lycocarpum that easily adapts to disturbed environments. The three southeastern populations, although fragmented, had preserved native vegetation and were not significantly different from each other (θp = 0.002).All other population pairs compared were significantly divergent (θp varied from 0.03 to 0.11 between pairs, P < 0.05). We found three distinct sets of allele frequencies. The three southeastern populations shared similar gene pools, as well as the two disturbed southern populations, which are secondary vegetation. The southern population located in protected area had the most dissimilar gene pool. In conclusion, populations showing a higher degree of human disturbance tends to show a larger population differentiation than expected from the isolation by distance model, which in the current scenario of the Cerrado destruction points out to a threat to the long-term conservation of the species.

Simulating the selfing and migration of Luehea divaricata populations in the Pampa biome to investigate the conservation potential of their genetic resources

“…They did not observe inbreeding in the population (f = 0.003), the mean coancestry value was low (θ = 0.0199), and the number of alleles observed was 45, in the genetic characterization of 24 accessions of T. grandiflorum, using microsatellite markers. Similar results (f = 0.002 and F = 0.07) were obtained by Moura et al (2012) when studying the genetic structure in fragmented populations of Solanum lycocarpum A. St.-Hil. in the Cerrado region of Brazil.…”

Chloroplast diversity of Casearia grandiflora in the Cerrado of Piauí State

“…According to Moura et al (2012) in natural populations, one of the main factors that influence the genetic structure of populations is the mating system, which determines the extent of gene flow between populations. Outcrossing plants, unlike autogamous ones, tend to have high levels of genetic variability within populations and low genetic differentiation between populations (Zanella et al, 2012).…”

“…The conservation is a necessary condition for maintaining biodiversity levels and is an important component for the sustainability of natural populations (Moura et al, 2012). The fragmentation of natural habitats and the spatial isolation of populations may cause changes in basic evolutionary processes, such as genetic drift, selection, and migration, resulting in changes in their genetic diversity and structure .…”

Habitat fragmentation decreased the genetic variability of Trichilia elegans A. Juss. (Meliaceae) in southern Brazil

“…is a common component of seasonal forests, that occurs from Venezuela to Uruguay. This specie is shadetolerant and shows zoochoric dispersion (LEHN et al, 2008), which make it susceptible to the fragmentation and the edge effects as well can have negative impact to its genetic conservation (MOURA et al, 2012).…”