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1.
PLoS One ; 13(3): e0192165, 2018.
Article in English | MEDLINE | ID: mdl-29513673

ABSTRACT

The primary focus of tropical forest restoration has been the recovery of forest structure and tree taxonomic diversity, with limited attention given to genetic conservation. Populations reintroduced through restoration plantings may have low genetic diversity and be genetically structured due to founder effects and genetic drift, which limit the potential of restoration to recover ecologically resilient plant communities. Here, we studied the genetic diversity, genetic structure and differentiation using single nucleotide polymorphisms (SNP) markers between restored and natural populations of the native tree Casearia sylvestris in the Atlantic Forest of Brazil. We sampled leaves from approximately 24 adult individuals in each of the study sites: two restoration plantations (27 and 62 years old) and two forest remnants. We prepared and sequenced a genotyping-by-sequencing library, SNP markers were identified de novo using Stacks pipeline, and genetic parameters and structure analyses were then estimated for populations. The sequencing step was successful for 80 sampled individuals. Neutral genetic diversity was similar among restored and natural populations (AR = 1.72 ± 0.005; HO = 0.135 ± 0.005; HE = 0.167 ± 0.005; FIS = 0.16 ± 0.022), which were not genetically structured by population subdivision. In spite of this absence of genetic structure by population we found genetic structure within populations but even so there is not spatial genetic structure in any population studied. Less than 1% of the neutral alleles were exclusive to a population. In general, contrary to our expectations, restoration plantations were then effective for conserving tree genetic diversity in human-modified tropical landscapes. Furthermore, we demonstrate that genotyping-by-sequencing can be a useful tool in restoration genetics.


Subject(s)
Casearia/genetics , Conservation of Natural Resources/methods , Forests , Genetic Variation , Genome, Plant/genetics , Trees/genetics , Brazil , Casearia/growth & development , Genetics, Population , Genotype , Models, Genetic , Polymorphism, Single Nucleotide , Sequence Analysis, DNA , Trees/growth & development
2.
J Hered ; 109(3): 264-271, 2018 03 16.
Article in English | MEDLINE | ID: mdl-29136171

ABSTRACT

The reproductive system of a tree species has substantial impact on genetic diversity and structure within and among natural populations. Such information, should be considered when planning tree planting for forest restoration. Here, we describe the mating system and genetic diversity of an overexploited Neotropical tree, Myroxylon peruiferum L.f. (Fabaceae) sampled from a forest remnant (10 seed trees and 200 seeds) and assess whether the effective population size of nursery-grown seedlings (148 seedlings) is sufficient to prevent inbreeding depression in reintroduced populations. Genetic analyses were performed based on 8 microsatellite loci. M. peruiferum presented a mixed mating system with evidence of biparental inbreeding (t^m-t/ = 0.118). We found low levels of genetic diversity for M. peruiferum species (allelic richness: 1.40 to 4.82; expected heterozygosity: 0.29 to 0.52). Based on Ne(v) within progeny, we suggest a sample size of 47 seed trees to achieve an effective population size of 100. The effective population sizes for the nursery-grown seedlings were much smaller Ne = 27.54-34.86) than that recommended for short term Ne ≥ 100) population conservation. Therefore, to obtain a reasonable genetic representation of native tree species and prevent problems associated with inbreeding depression, seedling production for restoration purposes may require a much larger sampling effort than is currently used, a problem that is further complicated by species with a mixed mating system. This study emphasizes the need to integrate species reproductive biology into seedling production programs and connect conservation genetics with ecological restoration.


Subject(s)
Genetic Variation , Myroxylon/physiology , Brazil , Forests , Inbreeding , Microsatellite Repeats , Myroxylon/genetics , Seedlings/genetics , Seeds/genetics
3.
Rev Soc Bras Med Trop ; 43(6): 620-3, 2010.
Article in English | MEDLINE | ID: mdl-21181010

ABSTRACT

INTRODUCTION: Human herpesviruses are frequently associated with orofacial diseases in humans (HSV-1, EBV, CMV and HHV-8), some can also cause systemic disease (CMV and HHV-8). The transmission of these viruses occurs by contact with infected secretions, especially saliva. Human immunodeficiency virus infection is associated with an increased risk of HHVs and related diseases. METHODS: This work aimed to detect HSV-1, EBV, CMV and HHV-8 DNA in saliva of HIV-infected patients from Teresina, northeast Brazil, by PCR and compare these findings with age and sex matched HIV-seronegative individuals. RESULTS: No difference in prevalence was verified between HHV detection in the saliva of HIV-seropositive individuals and controls. The individual frequencies of these viruses in these two populations were different. HIV seropositivity correlated positively with the presence of CMV (OR: 18.2, p= 0.00032) and EBV (OR: 3.44, p= 0.0081). No association between CD4 counts and the prevalence of HHVs in the saliva was observed; however, a strong association was determined between seropositivity and the presence of multiple HHV DNAs in saliva (OR: 4.83, p = 0.0028). CONCLUSIONS: These findings suggest the asymptomatic salivary shedding of HHVs is a common event between HIV-seropositive and seronegative individuals from Teresina, Piauí, Brazil, and, especially for HIV-seropositive patients, saliva is a risk factor for the acquisition/transmission of multiple HHVs.


Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , DNA, Viral/analysis , Herpesviridae Infections/diagnosis , Herpesviridae/genetics , Saliva/virology , Adult , Case-Control Studies , Female , Herpesviridae/classification , Herpesviridae/isolation & purification , Humans , Male , Polymerase Chain Reaction
4.
Rev. Soc. Bras. Med. Trop ; 43(6): 620-623, Nov.-Dec. 2010. tab
Article in English | LILACS | ID: lil-569418

ABSTRACT

INTRODUCTION: Human herpesviruses are frequently associated with orofacial diseases in humans (HSV-1, EBV, CMV and HHV-8), some can also cause systemic disease (CMV and HHV-8). The transmission of these viruses occurs by contact with infected secretions, especially saliva. Human immunodeficiency virus infection is associated with an increased risk of HHVs and related diseases. METHODS: This work aimed to detect HSV-1, EBV, CMV and HHV-8 DNA in saliva of HIV-infected patients from Teresina, northeast Brazil, by PCR and compare these findings with age and sex matched HIV-seronegative individuals. RESULTS: No difference in prevalence was verified between HHV detection in the saliva of HIV-seropositive individuals and controls. The individual frequencies of these viruses in these two populations were different. HIV seropositivity correlated positively with the presence of CMV (OR: 18.2, p= 0.00032) and EBV (OR: 3.44, p= 0.0081). No association between CD4 counts and the prevalence of HHVs in the saliva was observed; however, a strong association was determined between seropositivity and the presence of multiple HHV DNAs in saliva (OR: 4.83, p = 0.0028). CONCLUSIONS: These findings suggest the asymptomatic salivary shedding of HHVs is a common event between HIV-seropositive and seronegative individuals from Teresina, Piauí, Brazil, and, especially for HIV-seropositive patients, saliva is a risk factor for the acquisition/transmission of multiple HHVs.


INTRODUÇÃO: Alguns herpesvírus humanos são frequentemente associados a doenças orofaciais em humanos. A transmissão destes vírus ocorre através do contato com secreções contaminadas, especialmente a saliva. A infecção pelo vírus da imunodeficiência humana é considerada um fator de risco para a aquisição de HHVs e doenças correlatas. MÉTODOS: Este trabalho teve como objetivo detectar por PCR o DNA de HSV-1, EBV, CMV e HHV-8 na saliva de pacientes infectados com HIV em Teresina, nordeste do Brasil, e comparar os dados obtidos com o grupo controle (indivíduos HIV negativos). RESULTADOS: Não há diferença na prevalência de detecção de HHVs na saliva de indivíduos HIV soropositivos e soronegativos. No entanto, as frequências individuais de detecção dos diferentes HHVs são diferentes entre estas duas populações. A soropositividade para HIV apresentou correlação positiva com a presença de CMV (OR: 18,2, p = 0,00032) e EBV (OR: 3,44, p = 0,0081). Não foi verificada nenhuma associação entre a contagem de CD4 e prevalência de HHVs na saliva, no entanto existe uma forte associação entre a soropositividade e a detecção do DNA de vários HHVs na saliva (OR: 4,83, p = 0,0028). CONCLUSÕES: Estes resultados sugerem que a transmissão salivar de HHVs é um evento comum entre os indivíduos HIV soropositivos e soronegativos de Teresina, Piauí, Brasil, e, especialmente para os pacientes soropositivos, a saliva é um fator de risco para a aquisição/transmissão de múltiplos HHVs.


Subject(s)
Adult , Female , Humans , Male , AIDS-Related Opportunistic Infections/diagnosis , DNA, Viral/analysis , Herpesviridae Infections/diagnosis , Herpesviridae/genetics , Saliva/virology , Case-Control Studies , Herpesviridae/classification , Herpesviridae/isolation & purification , Polymerase Chain Reaction
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