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The genus Helicoverpa (Lepidoptera: Noctuidae) includes phytophagous and polyphagous agricultural insect pests. In the Americas, a native pest, Helicoverpa zea (Boddie), and an invasive pest, Helicoverpa armigera (Hübner), are causing severe damage in vegetable and agronomic crops. The population structure of both species in South America is poorly understood, and the phylogenetic relatedness of H. armigera and H. zea suggests natural interspecific gene flow between these species. Using microsatellite loci, we investigated: 1) the genetic diversity and gene flow of H. armigera specimens from Brazil; 2) the genetic diversity and gene flow between H. zea specimens from Brazil and the United States; and 3) the possibility of interspecific gene flow and the frequency of putative hybrids in Brazil. We detected high intraspecific gene flow among populations collected in the same country. However, there is a geographic limit to gene flow among H. zea individuals from South and North America. Pairwise Fst and private alleles showed that H. armigera is more similar to H. zea from Brazil than H. zea from the United States. A comparative STRUCTURE analysis suggests natural hybridization between H. armigera and H. zea in Brazil. High gene flow and natural hybridization are key traits to population adaptation in new and disturbed environments, which can influence the management of these pests in the American continent. [ABSTRACT FROM AUTHOR]

We present the development of a genomic library using RADseq (restriction site associated DNA sequencing) protocol for marker discovery that can be applied on evolutionary studies of the sugarcane borer Diatraea saccharalis, an important South American insect pest. A RADtag protocol combined with Illumina paired-end sequencing allowed de novo discovery of 12 811 SNPs and a high-quality assembly of 122.8M paired-end reads from six individuals, representing 40 Gb of sequencing data. Approximately 1.7 Mb of the sugarcane borer genome distributed over 5289 minicontigs were obtained upon assembly of second reads from first reads RADtag loci where at least one SNP was discovered and genotyped. Minicontig lengths ranged from 200 to 611 bp and were used for functional annotation and microsatellite discovery. These markers will be used in future studies to understand gene flow and adaptation to host plants and control tactics. [ABSTRACT FROM AUTHOR]

With 1 figure and 1 table The Guineagrass (Panicum maximum Jacq.) is one of the most important tropical forage grasses, but genetic knowledge and tools regarding this species are still limited. Therefore, 20 novel polymorphic microsatellite markers were developed, validated, and employed in estimating genetic relationships among 25 P. maximum genotypes selected from a Brazilian germplasm collection. In addition, they were tested for cross‐species amplification in four other forage grass species. The number of alleles observed for each locus ranged from 4 to 12 (average 6.7). The values of polymorphism information content (PIC) varied from 0.41 to 0.83 (average 0.61) and the discriminating power (D) ranged from 0.53 to 0.98 (average 0.72). Cross‐amplification demonstrated the potential transferability of these microsatellites to four tropical forage grass species. Cluster analysis based on the unweighted pair group method revealed three distinct groups: two clusters consisted of P. maximum genotypes and a third cluster, consisted of the other tropical forage grass species. The data demonstrated that the microsatellites developed herein have potential for germplasm characterization and genetic diversity analysis in P. maximum and other forage grass species. [ABSTRACT FROM AUTHOR]

With 3 tables Yellow and sweet passion fruit are insect‐pollinated species native to the tropics. Fruits are used commercially for human consumption worldwide. The yellow passion fruit is an outcrossing species with self‐incompatible flowers. However, the reproductive system of the sweet passion fruit (Passiflora alata) has not been well elucidated. The objective of this work was to characterize aspects of the mating system in the sweet passion fruit using random amplified polymorphic DNA (RAPD) and microsatellite markers, particularly the rate of outcrossing in P. alata progenies. A multilocus outcrossing rate of tm = 0.994 was determined from RAPD and tm = 0.940 from microsatellites, supporting P. alata as an outcrossing species. The fixation indices of the maternal generation (Fm) were −0.200 and 0.071 with RAPD and microsatellite loci, respectively, indicating the absence of inbreeding in the maternal generation. The paternity correlation (rp) varied from −0.008 with RAPD markers to 0.208 with microsatellite markers, suggesting a low probability of finding full sibs within the progenies. The results demonstrated that all progenies assessed in this study were derived from outcrossing. [ABSTRACT FROM AUTHOR]

Premise of the study: Paspalum atratum is a perennial, cespitose, tropical grass native to Central and South America. This species belongs to a polyploid complex (Plicatula group) little known at the genetic level. The characterized microsatellite markers provide new informative tools for further studies of the hybridization, mating systems, and structure of the population. Methods and Results: Using the microsatellite-enriched library method, we isolated and characterized 19 microsatellite markers from P. atratum . Eleven of them were polymorphic, showing a variable degree of variation, while eight were monomorphic in the samples analyzed. Additionally, the transferability of these microsatellite markers was tested in other species. Conclusions: These results suggest that the characterized markers have enough discriminatory potential to be used in genetic characterizations of Paspalum taxa, which are based on an understanding of their mating systems and genetic structure, as well as in understanding the evolutionary processes involved in the evolution of groups of Paspalum . [ABSTRACT FROM AUTHOR]

With 1 figure and 1 table Curcuma longa L. is a sterile, triploid, vegetatively-propagated crop cultivated mainly in Southeast Asia. When dried rhizomes are ground, the resulting yellow powder is used by the food industry as a natural food dye. Moreover, many pharmacological compounds have broadened the commercial application of the crop. However, conventional breeding is difficult and hence, improvement has been limited to germplasm selection. To better utilize the germplasm collections and facilitate genotype selection, a total of 17 polymorphic microsatellite loci were developed using a CT/GT/CTT enriched genomic library. All microsatellites resulted in amplified PCR products, showing a banding pattern of 2-11 polymorphic bands per locus, enabling genotype discrimination. These results can be used in further studies aimed at characterizing C. longa genetic resource collections and also to improve breeding strategies. [ABSTRACT FROM AUTHOR]

Brachiaria humidicola (Rendle) Schweick. is a warm-season grass commonly used as forage in the tropics. Accessions of this species were collected in eastern Africa and massively introduced into South America in the 1980s. Several of these accessions form a germplasm collection at the Brazilian Agricultural Research Corporation. However, apomixis, ploidy, and limited knowledge of the genetic basis of this germplasm collection have constrained breeding activities. The objectives of this work were to identify genetic variability in the Brazilian B. humidicola germplasm collection using microsatellite markers and to compare the results with information on the following: (1) collection sites of the accessions; (2) reproductive mode and ploidy levels; and (3) genetic diversity revealed by morphological traits. The evaluated germplasm population is highly structured into four major groups. The sole sexual accession did not group with any of the clusters. Genetic dissimilarities did not correlate with either geographic distances or genetic distances inferred from morphological descriptors. Additionally, the genetic structure identified in this collection did not correspond to differences in ploidy level. Alleles exclusive to either sexual or apomictic accessions were identified, suggesting that further evaluation of the association of these loci with apospory should be carried out. Le Brachiaria humidicola (Rendle) Schweick. est une graminée des climats chauds fréquemment employée comme plante fourragère dans les tropiques. Des accessions de cette espèce ont été collectés en Afrique de l'Est et massivement introduites dans les Amériques au cours des années 1980. Plusieurs de ces accessions sont représentées au sein d'une collection de ressources génétiques maintenue par le Brazilian Agricultural Research Corporation. Cependant, l'apomixie, la ploïdie et des connaissances limitées des bases génétiques des accessions de cette collection ont restreint les efforts de sélection. Les objectifs de ce travail étaient d'identifier la variabilité génétique au sein de la collection brésilienne du B. humidicola au moyen de microsatellites et de comparer les résultats avec les informations suivantes : 1) le lieu de collection des accessions ; 2) le mode de reproduction et le niveau de ploïdie ; et 3) la diversité génétique mesurée sur la base des caractères morphologiques. La collection de ressources génétiques examinée forme quatre groupes majeurs très distincts. La seule accession à reproduction sexuée se distinguait des quatre autres groupes. Le degré de différenciation génétique n'était corrélé ni avec la distance géographique ni avec la distance génétique mesurée sur la base des caractères morphologiques. De plus, la structure génétique identifiée au sein de la collection ne correspond pas à des différences quant aux niveaux de ploïdie. Les allèles présents uniquement au sein d'accessions sexuées ou apomictiques ont été identifiés et une évaluation ultérieure de l'association entre ces locus et l'aposporie serait utile. [ABSTRACT FROM AUTHOR]

Melipona interrupta manaosensis is an important pollinator in the Neotropics. This stingless bee is reared by locals for honey production and also for conservation purposes. Eleven microsatellite markers were isolated from M. i. manaosensis and characterized in 32 individuals from the Meliponary of the Instituto Nacional de Pesquisas da Amazônia, Manaus, AM, Brazil. The number of alleles observed for each locus ranged from 2 to 5 (average 2.77). The polymorphism information content (PIC) varied between 0.08 to 0.62 (average 0.34) and the discriminating power (D) ranged from 0.61 to 0.99 (average 0.85). The observed heterozygosity ( H ) and the expected heterozygosity ( H ) ranged from 0.04 to 1.00 and 0.04 to 0.67, respectively. These microsatellites will be useful for future genetic studies of M. i. manaosensis populations and correlated species contributing with Amazon biodiversity preservation. [ABSTRACT FROM AUTHOR]

Lychnophora pinaster Mart. (Asteraceae) is a Brazilian medicinal plant, extensively employed in popular medicine as an anti-inflammatory, analgesic and healing agent. Thirteen polymorphic microsatellite markers were developed and optimized for L. pinaster from an enriched genomic library. The markers were used to analyse 37 plants from two native populations, generating an average number of 6.6 alleles per polymorphic locus. These loci are important tools for future studies of population genetics. [ABSTRACT FROM AUTHOR]

Abstract Aim: To study the response of the bacterial community to bioremediation of a soil with an aged contamination of crude oil. Methods and Results: The bacterial community in laboratory soil columns during a 72-day biostimulation treatment was followed by analysing the number of total cultivable hydrocarbon-degrading bacteria, soil respiratory activity and the 16S–23S rDNA internal transcribed spacer homoduplex heteroduplex polymorphisms (ITS-HHP) of total soil bacterial DNA. ITS-HHP permits an estimate of both length and sequence polymorphism in a 16S–23S rDNA spacer population, using to advantage the homoduplex and heteroduplex fragments that are generated during PCR. The treatment, made by air sparging and biostimulation with a mineral nutrient and surfactant solution, resulted in a 39·5% decrease of the total hydrocarbon content. Within 4 days of treatment onset the bacterial community underwent a first phase of activation that led to a substantial increase in the observable diversity. Subsequently, after a 12-day period of stability, another activation phase was observed with further shifts of the community structure and an increase in the abundance and diversity of catechol-2,3-dioxygenase (C23O) genes. Conclusions: The overall data suggest an important contribution of uncultivable bacteria to the soil bioremediation, since, during the second activation phase, the increases of the respiratory activity, bacterial diversity and C23O gene abundance and diversity were not accompanied by a corresponding increase of the cultivable bacteria number. Significance and Impact of the Study: This study shows that successive phases of activation of bacterial populations occur during a bioremediation treatment of oil-polluted soil. [ABSTRACT FROM AUTHOR]

Abstract Aim: To study the response of the bacterial community to bioremediation of a soil with an aged contamination of crude oil. Methods and Results: The bacterial community in laboratory soil columns during a 72-day biostimulation treatment was followed by analysing the number of total cultivable hydrocarbon-degrading bacteria, soil respiratory activity and the 16S–23S rDNA internal transcribed spacer homoduplex heteroduplex polymorphisms (ITS-HHP) of total soil bacterial DNA. ITS-HHP permits an estimate of both length and sequence polymorphism in a 16S–23S rDNA spacer population, using to advantage the homoduplex and heteroduplex fragments that are generated during PCR. The treatment, made by air sparging and biostimulation with a mineral nutrient and surfactant solution, resulted in a 39·5% decrease of the total hydrocarbon content. Within 4 days of treatment onset the bacterial community underwent a first phase of activation that led to a substantial increase in the observable diversity. Subsequently, after a 12-day period of stability, another activation phase was observed with further shifts of the community structure and an increase in the abundance and diversity of catechol-2,3-dioxygenase (C23O) genes. Conclusions: The overall data suggest an important contribution of uncultivable bacteria to the soil bioremediation, since, during the second activation phase, the increases of the respiratory activity, bacterial diversity and C23O gene abundance and diversity were not accompanied by a corresponding increase of the cultivable bacteria number. Significance and Impact of the Study: This study shows that successive phases of activation of bacterial populations occur during a bioremediation treatment of oil-polluted soil. [ABSTRACT FROM AUTHOR]

Casearia sylvestris Sw. is a widespread neotropical tree utilized in popular medicine. Recent research ranked Casearia as one of the most promising genus in the search of drugs against cancer. Despite its wide distribution and pharmacological importance, no microsatellite markers have yet been developed for this genus. In this study, we provide 10 polymorphic microsatellite loci specifically designed for C. sylvestris, used to analyse 90 individuals distributed in two populations from São Paulo state, Brazil. On average, 12.3 alleles per locus were identified, showing the ability of the markers to detect microsatellite polymorphism in this species. [ABSTRACT FROM AUTHOR]

Macaw ( Acrocomia aculeata) is a native palm tree from tropical forests, highly abundant in Brazil and cited as one of the principal sources of plant oil, thus presenting a high potential for biodiesel production. We have optimized and utilized a set of eight polymorphic microsatellite markers for A. aculeata from an enriched genomic library. Automatic sequencing and fluorescence detection were employed to analyse 43 individuals from natural populations. In this study, we have obtained an average number of five alleles per locus. These loci will be employed in future studies of population genetics by providing subsidy information for the species conservation and genetic breeding. [ABSTRACT FROM AUTHOR]

Passiflora alata is one of the commercialized species of the passion vines, grown for its edible fruits. It is found in South America, mainly Paraguay, Argentina, Peru and Brazil. The development of a set of microsatellite markers was proposed to provide tools for analysing both genetic structure of wild populations and the reproductive system of the species, which are poorly understood. Seven markers were developed from a P. alata-genomic library enriched for simple sequence repeats (SSR). Twelve individuals were genotyped, and the levels of the expected heterozygosity ( HE) did show that those markers could be used to develop P. alata genetic studies. [ABSTRACT FROM AUTHOR]

Here we described the development of the first set of Passiflora microsatellite loci isolated from an enriched genomic library. A sample of 43 individuals from 12 accessions of the yellow passion fruit was used to characterize those loci, which revealed up to 20 alleles per locus. Two loci were monomorphic. The observed (HO) and expected (HE) heterozygosities were very similar, as expected for a self-incompatible species. A llelic diversity (HT) was 0.444. This set of markers will permit genetic structure analyses of cultivated and wild populations of Passiflora, and contribute for integrating genetic maps based on dominant markers, as they can provide bridge alleles. [ABSTRACT FROM AUTHOR]

The RADP (Random amplified polymorphic DNA) technique was used to detect tissue-culture-induced variations in sugarcane. Plants of the Brazilian variety RB83-5486 propagated via rhizomes and via meristem cultures were studied. The polymorphism rate for 98 RAPD loci was 6.93% when the plants derived from meristems. Besides, in order to evaluate the influence of the number of subcultures on the generation of somaclonal variation, field-grown RB83-5486 plants derived from 10 meristems were studied after five subcultivations. Although different rates of polymorphism were observed, there was no direct association with the stage of subcultivation. The analysis of plants of two sugarcane varieties cultivated in vitro from meristems showed that variety RB83-5486 was more unstable than variety SP80-185.

Este trabalho analisa pesquisas recentes que estudam a associação entre depressão na gravidez e prematuridade. A difusão de informações científicas faz dessa categoria nosográfica (depressão) uma presença constante e, muito freqüentemente, imprecisa, nos discursos do senso comum. No campo da saúde mental, são várias as áreas que a abordam e de modos bastante diversos. Por outro lado, apesar de haver indicações sugerindo a influência de estados emocionais em desfechos orgânicos, permanecem dificuldades em demonstrá-la através dos métodos convencionais de pesquisa científica. Parece que um dos problemas em associar depressão à prematuridade deve-se a aspectos epistemológicos relacionados à demarcação teórica da depressão.

Cagaita ( Eugenia dysenterica) is a widespread plant found in the Brazilian cerrado. Its fruit is used for popular consumption and for industrial purposes. A battery of 346 primer pairs developed for Eucalyptus spp. was tested on cagaita. Only 10 primer pairs were found to be transferable between the two species. Using a polyacrilamide gel, an average of 10.4 alleles per locus was detected, in a sample of 116 individuals from 10 natural populations of cagaita. Seven polymorphic loci allowed estimation of genetic parameters, including expected average heterozigosity HE = 0.442, diversity among populations, RST = 0.268 and gene flow Nm = 0.680. [ABSTRACT FROM AUTHOR]

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 ampliied 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 ampliied 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 identiied for L. sidoides and L. gracilis accessions in the AGB, and Lippia sp sampled plants, respectively. Analyses of genetic structure permitted the identiication 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. [ABSTRACT FROM AUTHOR]

A microsatellite-enriched library was constructed and a set of 19 SSR markers were developed to characterize a germplasm collection of Hyptis pectinata (L.) Poit., maintained at the Universidade Federal de Sergipe (UFS). Fifteen markers of 19 ranged from moderately to highly polymorphic. A total of 113 alleles were identified, with a mean of 7.52 alleles per locus. The mean HO and HE were 0.582 and 0.657, respectively. The primers developed were efficient tools for accessing the genetic diversity of the germplasm collection analyzed and may also be useful for other studies involving this species and other species in the genus Hyptis. [ABSTRACT FROM AUTHOR]

Xanthomonas axonopodis pv. passiflorae causes bacterial spot in passion fruit. It attacks the purple and yellow passion fruit as well as the sweet passion fruit. The diversity of 87 isolates of pv. passiflorae collected from across 22 fruit orchards in Brazil was evaluated using molecular profiles and statistical procedures, including an unweighted pair-group method with arithmetical averages-based dendrogram, analysis of molecular variance (AMOVA), and an assigning test that provides information on genetic structure at the population level. Isolates from another eight pathovars were included in the molecular analyses and all were shown to have a distinct repetitive sequence-based polymerase chain reaction profile. Amplified fragment length polymorphism technique revealed considerable diversity among isolates of pv. passiflorae, and AMOVA showed that most of the variance (49.4%) was due to differences between localities. Cluster analysis revealed that most genotypic clusters were homogeneous and that variance was associated primarily with geographic origin. The disease adversely affects fruit production and may kill infected plants. A method for rapid diagnosis of the pathogen, even before the disease symptoms become evident, has value for producers. Here, a set of primers (Xapas) was designed by exploiting a single-nucleotide polymorphism between the sequences of the intergenic 16S-23S rRNA spacer region of the pathovars. Xapas was shown to effectively detect all pv. passiflorae isolates and is recommended for disease diagnosis in passion fruit orchards. [ABSTRACT FROM AUTHOR]