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The restoration projects in the Brazilian Atlantic Forest have shown more concern about genetic variability in floristic diversity in the last years. To create effective conservation policies, we need extensive knowledge on structures and patterns of genetic variation between natural populations and within them. We characterized the genetic population of Casearia sylvestris Swartz in an area under forest restoration processes (Iracemapolis, Sao Paulo) established between 1988 and 1990, and compared it to a natural remnant of semi-deciduous seasonal forest (Caetetus, Sao Paulo). The distance between locations is ∼ 210 km. One hundred twenty-eight adult plants were collected, 64 individuals in the native forest remnant and 64 in the restored fragment. The genetic data were generated by the screening of six AFLP primers combinations with a total of 296 loci for each population. The forest restoration site presented overall higher levels of genetic diversity compared to the natural remnant area. The most likely number of genetic clusters found was three (K = 3). The genetic variation was higher within populations, either in the natural or restored site, than between populations. Farther, 25 candidate outlier loci were selected and separated into two groups giving support to future research with species adaptation in these different environments. Our results show that evaluation of restored tree populations of C. sylvestris is crucial to monitoring long-term restoration programs and understand if they persist over time. We hope that our results aim at species management and the establishment of others restoration projects.

Human-mediated changes in landscapes can facilitate niche expansion and accelerate the adaptation of insect species. The interaction between the evolutionary history of the sugarcane borer, Diatraea saccharalis Fabricius, and historical and modern agricultural activity in Brazil shaped its spatial genetic structure, facilitating ecological divergence and incipient host shifting. Based on microsatellite data, STRUCTURE analyses identified two (K = 2) and three (K = 3) significant genetic clusters that corresponded to: (a) a strong signal of spatial genetic structure and, (b) a cryptic signal of host differentiation. We inferred that K = 2 reflects the footprint of agricultural activity, such as expansion of crop production (sugarcane and maize), unintentional dispersion of pests, and management practices. In contrast, K = 3 indicated incipient host differentiation between larvae collected from sugarcane or maize. Our estimates of population size changes indicated that a historical bottleneck was associated with a reduction of sugarcane production ≈200 years ago. However, a more recent population expansion was detected (>1950s), associated with agricultural expansion of large crop production into previously unfarmed land. Partial Mantel tests supported our hypothesis of incipient host adaptation, and identified isolation-by-environment (e.g., host plant) in São Paulo and Minas Gerais states, where sugarcane has been traditionally produced in Brazil. The impact of agricultural production on D. saccharalis may continue, as the current population structure may hinder the efficacy of refuge plants in delaying insect resistance evolution to Bt toxin.

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^s = 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.

One of the major strategies used to prevent extinction of forest species is restoration of previously depleted areas. In this paper, we investigate the ability of forest restoration to produce tree populations with high genetic diversity in previously deforested areas. We used nine SSR markers to genotype populations of two forest restorations and two areas of natural remnants. There were no significant differences between natural forest remnants and restored forests with respect to inbreeding levels (f = 0.20) or genetic diversity, as assessed by levels of heterozygosity (HS ∼ 0.31–0.43) and allelic richness (2.41–2.94). Instead, we found evidence of gene flow from neighbouring woods to restored forests. Although some populations may show a lower number of private alleles, this would be an expected result of a bottleneck effect in reduced populations such as those in forest restorations. Although the loss of these low frequency alleles has no major consequences for genetic diversity, the impact on population fitness in a scenario of environmental change is unpredictable.

Due to the economic interests in vetiver, Chrysopogon zizanioides (L.) Roberty, molecular and chemical studies are essential to generate information for its sustainable exploitation. The aim of this study was to undertake a molecular and chemical characterization of vetiver accessions of the active germplasm bank of the Universidade Federal de Sergipe. The molecular characteristics of the accessions were studied using amplified fragment length polymorphism markers, with a total of 14 primer combinations that generated 442 loci, allowing us to observe that these accessions have similar genomes. The vetiver accessions were divided into three distinct groups, where accession UFS-VET005 was the most differentiated and accession UFS-VET004 had the lowest essential oil content (0.70%). The content of the chemical constituents of the essential oils was observed to vary, with a predominance of khusimol, which ranged from 18.97 to 25.02%. It was possible to divide the vetiver accessions into two groups based on chemical composition, and these groups do not correlate with the molecular grouping. Therefore, it is necessary to perform molecular and chemical analyses to characterize vetiver accessions.

The sugarcane borer or corn stalk borer, Diatraea Guilding is polyphagous insect pest of many important crops such as corn, sorghum and sugarcane. Losses arising from the attack of Diatraea species have been a serious problem, which may cause loss in sugarcane production around 0.25% in sugar, 0.20% in alcohol and 0.77% of body weight for every 1% infestation and up to 21% in corn production fields. In Brazil, the most commonly reported species are Diatraea saccharalis (Fabricius, 1794) and Diatraea impersonatella (Walker, 1863) (= D. flavipennella). However, multiple other species of Diatraea have been identified in Brazil according to the literature. Currently, little information exists on the presence of the other species causing injury to sugarcane and corn. The objectives of this study were to improve the accuracy of species assignment, evaluate the population genetic structure, and address many of the outstanding questions of systematics and evolution of Brazilian populations of D. saccharalis. To address these main questions, classical taxonomic methods were used, focused on morphological characterization of the reproductive organs, especially the male genitalia. In addition, genetic studies were performed using simple sequence repeats (SSR) and a fragment of cytochrome C oxidase subunit I (COI) gene. The data and findings from this research will contribute to the understanding of evolutionary aspects of insect pests in order to develop more effective and sustainable population management practices.

Soybean is a globally important oil crop, and the flavour, stability and nutritional value of soybean oil is dependent on the relative proportions of five primary fatty acids. In this study, association mapping was performed to identify molecular markers associated with QTL regions related to oil traits in soybean. Oil and fatty acid contents were measured in soybean accessions grown under field conditions for 2 years. Based on polymorphisms at 142 SSR loci, 94 soybean accessions were divided into two clusters corresponding to accessions from Asian and American gene pools. Linkage disequilibrium (LD) among the SSR loci suggested a structure across the soybean genome (LD decay) of approximately 12 cM. Pairwise kinship estimates among the accessions showed low values. A mixed linear model (MLM) adjusted using false discovery rate (FDR) and minimum Bayes factor (BFmin) values identified 110 strongly associated marker-traits. Oleic acid content had the highest number of associated SSR loci (33), followed by linoleic acid (26), palmitic acid (24), oil (16) and linolenic acid (14). Specific alleles at eight loci yielded high performing soybeans with respect to fatty acid content, and these are presented in a crossing matrix. Analysis of SSR loci and oil traits confirmed previous findings, and many new markers were also identified that may be useful for quickly improving oil traits in soybean.

The sugarcane borer moth, Diatraea saccharalis, is one of the most important pests of sugarcane and maize crops in the Western Hemisphere. The pest is widespread throughout South and Central America, the Caribbean region and the southern United States. One of the most intriguing features of D. saccharalis population dynamics is the high rate of range expansion reported in recent years. To shed light on the history of colonization of D. saccharalis, we investigated the genetic structure and diversity in American populations using single nucleotide polymorphism (SNPs) markers throughout the genome and sequences of the mitochondrial gene cytochrome oxidase (COI). Our primary goal was to propose possible dispersal routes from the putative center of origin that can explain the spatial pattern of genetic diversity. Our findings showed a clear correspondence between genetic structure and the geographical distributions of this pest insect on the American continents. The clustering analyses indicated three distinct groups: one composed of Brazilian populations, a second group composed of populations from El Salvador, Mexico, Texas and Louisiana and a third group composed of the Florida population. The predicted time of divergence predates the agriculture expansion period, but the pattern of distribution of haplotype diversity suggests that human-mediated movement was most likely the factor responsible for the widespread distribution in the Americas. The study of the early history of D. saccharalis promotes a better understanding of range expansion, the history of invasion, and demographic patterns of pest populations in the Americas. Fil: Francischini, Fabricio J. B.. Universidade Estadual de Campinas. Instituto de Biología; Brasil Fil: Cordeiro, Erick M. G.. Universidade do Sao Paulo. Escola Superior de Agricultura Luiz de Queiroz; Brasil Fil: Campos, Jaqueline B. de. Universidade Estadual de Campinas. Instituto de Biología; Brasil Fil: Alves Pereira, Alessandro. Universidade Estadual de Campinas; Brasil Fil: Gomes Viana, João Paulo. Universidade Estadual de Campinas. Instituto de Biología; Brasil Fil: Wu, Xing. University of Illinois; Estados Unidos Fil: Wei, Wei. University of Illinois; Estados Unidos Fil: Brown, Patrick. University of Illinois; Estados Unidos Fil: Joyce, Andrea. University of California; Estados Unidos Fil: Murúa, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres" (p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; Argentina Fil: Fogliata, Sofia Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Provincia de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial "Obispo Colombres" (p). Instituto de Tecnología Agroindustrial del Noroeste Argentino; Argentina Fil: Clough, Steven J.. University of Illinois; Estados Unidos. United States Department of Agriculture; Estados Unidos Fil: Zucchi, María Inmaculada. Universidade Estadual de Campinas; Brasil

Guacatonga (Casearia sylvestris) is a native plant of the Atlantic Forest, with high medicinal potential and relevance for reforestation programs. The aim of this study was to characterize, with microsatellite markers, two populations of C. sylvestris from remaining areas of the Atlantic Forest in the State of Sao Paulo. High allelic variation was found in both populations (NA = 101 and 117; AR = 12.5 and 14.4), although with high endogamy coefficients (f = 0.640 and 0.363). Estimates of genetic structure suggested the presence of considerable genetic divergence between the populations (FST = 0.103); however, there was no spatial genetic structure within the populations. Genetic divergence may have occurred due to decreased gene flow between the fragmented populations as the result of deforestation. The results of this study demonstrate the importance of genetic diversity and its characterization in native plants within remaining forest areas for the management and restoration of such areas.

The conservation of plants in germplasm banks ensures the characterization and availability of these resources for future generations. The present study used DNA markers to obtain genetic information about germplasm collections of Lippia sidoides and L. gracilis, which are maintained in an Active Germplasm Bank (AGB). Genetic variability of samples in the AGB was assessed using 12 combinations of amplified fragment length polymorphism (AFLP) primers (EcoRI/MseI). Twenty simple sequence repeat primers designed for L. alba were tested to determine their transferability in L. sidoides and L. gracilis. The AFLP markers generated 789 markers. The assessed loci exhibited a moderate Shannon diversity index (I = 0.42) in both species, suggesting that the conserved accessions possess an intermediate level of genetic diversity. Twelve microsatellite loci amplified satisfactorily, and nine loci were polymorphic in each species. A total of 23, 22, and 36 alleles, with an average of 2.5, 2.4, and 3.27 alleles per locus were identified for L. sidoides and L. gracilis accessions in the AGB, and Lippia sp sampled plants, respectively. Analyses of genetic structure permitted the identification of three different groups using both sets of markers, of which two were representative of L. sidoides. The information generated in this study may help to create, expand, and maintain collections of these species and may assist in genetic-breeding programs.

Premise of the study: Baccharis dracunculifolia (Asteraceae) is a native plant of the Atlantic Forest that is used for the production of essential oil. Microsatellite markers were developed for this species to investigate the genetic diversity of three natural populations. Methods and Results: Seventeen out of 27 microsatellite loci identified in a genomic library used for the characterization of 315 individuals derived from three natural populations of B. dracunculifolia resulted in successful amplifications. Eleven polymorphic loci, ranging from two to seven alleles per locus, were obtained with expected and observed heterozygosity values ranging between 0.068 and 0.775 and 0.046 and 0.667, respectively. Conclusions: The microsatellite loci described in this study are tools that can be used for further studies of population genetics of B. dracunculifolia with a focus on deforested areas and conservation of natural populations.

Microsatellite primers were developed and optimized for Lippia alba to characterize the L. alba germplasm bank of Universidade de Sao Paulo. A genomic library enabled the design of 9 microsatellite primers. Six of the 9 primers yielded polymorphic products, which defined 2 groups in the bank. The data provide support to characterize germplasm banks, genetic breeding programs for L. alba, and other genetic diversity studies and classifications of species in the genus Lippia.

• Premise of the study: Microsatellite primers were designed for Piptadenia gonoacantha (Fabaceae) and characterized to estimate genetic diversity parameters. The species is a native tree from the Atlantic Forest biome commonly used in forest restoration; it has medicinal potential and the wood is economically useful. • Methods and Results: Twenty-eight microsatellite loci were identified from an enriched genomic library. Fifteen loci resulted in successful amplifications and were characterized in a natural population of 94 individuals. Twelve loci were polymorphic, with allele numbers ranging from three to 15 per locus, and expected and observed heterozygosities ranging from 0.2142 to 0.8325 and 0.190 to 0.769, respectively. • Conclusions: The developed markers will be used in further studies of population genetics of P. gonoacantha, aimed at conservation and management of the species in natural populations and in forest restoration projects.

We isolated and characterised eight pairs of primers to amplify microsatellite regions for Centrolobium tomentosum, a neotropical tree species widely used for forest restoration, with important pharmacological potential. For the primer characterisation, we genotyped 48 individuals from two populations of C. tomentosum from natural remnants of Atlantic Rainforests. We detected 2–9 alleles per locus, observed and expected heterozygosities ranged from 0.08 to 0.72, and 0.08 to 0.83, respectively and we observed private alleles in six of the loci. No linkage disequilibrium was observed and all loci are in Hardy–Weinberg Equilibrium in at least one of the populations. This study presents a powerful tool for population genetic studies of this species.