Analysis of the genetic relationships and diversity among 11 populations of Xanthoceras sorbifolia using phenotypic and microsatellite marker data

Background: Assessments of genetic diversity are essential for germplasm characterization and exploitation. Molecular markers are valuable tools for exploring genetic variation and identifying germplasm. They play key roles in a Xanthoceras sorbifolia breeding program. Results: We analyzed the genetic diversity of populations of this species using 23 simple sequence repeat (SSR) loci and data on kernel oil content. The 11 populations included in the study were distributed across a large geographic range in China. The kernel oil content differed significantly among populations. The SSR marker analysis detected high genetic diversity among the populations. All SSRs were polymorphic, and we identified 80 alleles across the populations. The number of alleles at each locus ranged from two to six, averaging 3.48 per primer pair. The polymorphism information content values ranged from 0.35 to 0.70, averaging 0.51. Expected heterozygosity, observed heterozygosity, and Shannon's information index calculations detected large genetic variations among populations of different provenance. The high average number of alleles per locus and the allelic diversity observed in the set of genotypes analyzed indicated that the genetic base of this species was relatively wide. The statistically significant positive correlation between genetic and geographic distances suggested adaptations to local conditions. Conclusions: Microsatellite markers can be used to efficiently distinguish X. sorbifolia populations and assess their genetic diversity. The information we have provided will contribute to the conservation and management of this important plant genetic resource.

Communities of endophytic microorganisms in different developmental stages from a local variety as well as transgenic and conventional isogenic hybrids of maize.

The diversity of endophytic microorganisms may change due to the genotype of the host plant and its phenological stage. In this study we evaluated the effect of phenological stage, transgenes and genetic composition of maize on endophytic bacterial and fungal communities. The maize populations were composed of a local variety named Rosado (RS) and three isogenic hybrids. One isogenic hybrid was not genetically modified (NGM). Another hybrid (Hx) contained the transgenes cry1F and pat (T1507 event), which provide resistance to insects of the order Lepidoptera and tolerance to the glufosinate-ammonium herbicide, respectively. The third hybrid (Hxrr) contained the transgene cp4 epsps (NK603 event) combined with the transgenes cry1F and pat (T1507 event), which allow tolerance to the Roundup Ready herbicide, besides the characteristics of Hx. Evaluation of the foliar tissue was done through PCR-DGGE analysis, with specific primers for bacteria and fungi within four phenological stages of maize. The endophytic bacteria were only clustered by phenological stages; the structure of the fungal community was clustered by maize genotypes in each phenological stage. The fungal community from the local variety RS was different from the three hybrids (NGM, Hx and Hxrr) within the four evaluated stages. In the reproductive stage, the fungal community from the two transgenic hybrids (Hx and Hxrr) were separated, and the Hxrr was different from NGM, in the two field experiments. This research study showed that the genetic composition of the maize populations, especially the presence of transgenes, is the determining factor for the changes detected in the endophytic fungal community of maize leaves.

Técnicas moleculares para caracterização e conservação de plantas medicinais e aromáticas: uma revisão / Molecular techniques for characterization and conservation of medicinal and aromatic plants: a review

RESUMO Os estudos que visam à caracterização e conservação de germoplasma de espécies de plantas medicinais e aromáticas vêm crescendo de forma expressiva frente ao potencial econômico dessas espécies. Para tanto, diferentes marcadores moleculares estão disponíveis no mercado, e a seleção de um ou mais marcadores requer o conhecimento de suas propriedades e aplicações. Este trabalho tem por objetivo apresentar uma revisão bibliográfica sobre as principais técnicas moleculares utilizadas nesses estudos.

ABSTRACT The studies which aim on the characterization and conservation of the germplasm from medicinal and aromatic plant species have been frequent, due to the economic potential of these species. Therefore, different molecular markers are available in the market, and the selection of one or more markers requires knowledge of their properties and applications. This work aims to present a literature review about the main molecular techniques used in these studies.

Genetic divergence among Dimorphandra spp. accessions using RAPD markers / Divergência genética entre acessos de Dimorphandra spp. usando marcadores RAPD

The genus Dimorphandra has distinguish relevance considering either medicinal or biodiversity aspects because it includes two species that are economically important flavonoids sources for pharmachemical industry (D. mollis Benth. and D. gardneriana Tul.), and species endemic to Brazil, such as D. jorgei Silva and D. wilsonii Rizz., threatened by extinction. In order to evaluate variability among accessions of D. mollis (fava-d'anta), D. gardneriana and D. wilsonii, it was collected fruit from individual plants from three Brazilian states in a total of 57 accessions, which were analyzed with RAPD markers. It was used 20 seeds per progeny; the DNA was extracted from fully-formed young leaves, which were collected in bulk. The data were analyzed using a binary matrix, in which the score one represented presence of a band and zero, absence. The similarity matrix was developed by using the arithmetic complement of the Jaccard index, later grouped based on the Neighbor Joining algorithm. It was found considerable intra and inter specific variability in Dimorphandra spp., which were separated into four groups. Though genetic variability was found, the collecting trips showed that most of these areas are subject to loss of genetic resources of fava-d'anta due to the following factors: continuous anthropic activity, propensity for natural fires, and loss of natural seed dispersers (large fruit-eating mammals). Therefore, protections of these areas and ex situ conservation are essentials for the maintenance of genetic variability of these species.

O gênero Dimorphandra tem grande relevância, sobretudo nos aspectos medicinais e de biodiversidade, por incluir duas espécies que são importantes economicamente como fontes de flavonoides para indústria farmacoquímica (D. mollis Benth. e D. gardneriana Tull.), e espécies endêmicas do Brasil, como a D. jorgei Silva e D. wilsonii Rizz., sendo esta ameaçada de extinção. Objetivando avaliar a variabilidade entre acessos de D. mollis, D. gardneriana e D. wilsonii, foram realizadas coletas de frutos separados por planta em três estados brasileiros em um total de 57 acessos que foram analisados por meio da técnica RAPD. Utilizaram-se vinte sementes por progênie e o DNA, extraído de folhas definitivas, jovens, e coletadas em bulk. Os dados foram analisados utilizando-se uma matriz de dados binários. Para formação da matriz de dissimilaridade, foi utilizado o complemento aritmético do Índice de Jaccard e posteriormente o agrupamento pelo algoritmo de Neighbor Joining. O estudo revelou que existe variabilidade entre e dentro das espécies de Dimorphandra spp., o qual formou quatro grupos. Apesar da variabilidade genética constatada, as expedições de coleta demonstraram que a maioria das áreas amostradas está sujeita a perdas de recursos genéticos de fava-d'anta devido aos seguintes fatores: ocorrência de ação antrópica contínua; propensão a incêndios naturais; e diminuição dos dispersores naturais de sementes (grandes mamíferos frugíveros). Assim, a proteção destas áreas e a conservação ex situ, são primordiais para manutenção da variabilidade genética dessas espécies.

Genetic divergence among Dimorphandra spp. accessions using RAPD markers

The genus Dimorphandra has distinguish relevance considering either medicinal or biodiversity aspects because it includes two species that are economically important flavonoids sources for pharmachemical industry (D. mollis Benth. and D. gardneriana Tul.), and species endemic to Brazil, such as D. jorgei Silva and D. wilsonii Rizz., threatened by extinction. In order to evaluate variability among accessions of D. mollis (fava-d'anta), D. gardneriana and D. wilsonii, it was collected fruit from individual plants from three Brazilian states in a total of 57 accessions, which were analyzed with RAPD markers. It was used 20 seeds per progeny; the DNA was extracted from fully-formed young leaves, which were collected in bulk. The data were analyzed using a binary matrix, in which the score one represented presence of a band and zero, absence. The similarity matrix was developed by using the arithmetic complement of the Jaccard index, later grouped based on the Neighbor Joining algorithm. It was found considerable intra and inter specific variability in Dimorphandra spp., which were separated into four groups. Though genetic variability was found, the collecting trips showed that most of these areas are subject to loss of genetic resources of fava-d'anta due to the following factors: continuous anthropic activity, propensity for natural fires, and loss of natural seed dispersers (large fruit-eating mammals). Therefore, protections of these areas and ex situ conservation are essentials for the maintenance of genetic variability of these species.

O gênero Dimorphandra tem grande relevância, sobretudo nos aspectos medicinais e de biodiversidade, por incluir duas espécies que são importantes economicamente como fontes de flavonoides para indústria farmacoquímica (D. mollis Benth. e D. gardneriana Tull.), e espécies endêmicas do Brasil, como a D. jorgei Silva e D. wilsonii Rizz., sendo esta ameaçada de extinção. Objetivando avaliar a variabilidade entre acessos de D. mollis, D. gardneriana e D. wilsonii, foram realizadas coletas de frutos separados por planta em três estados brasileiros em um total de 57 acessos que foram analisados por meio da técnica RAPD. Utilizaram-se vinte sementes por progênie e o DNA, extraído de folhas definitivas, jovens, e coletadas em bulk. Os dados foram analisados utilizando-se uma matriz de dados binários. Para formação da matriz de dissimilaridade, foi utilizado o complemento aritmético do Índice de Jaccard e posteriormente o agrupamento pelo algoritmo de Neighbor Joining. O estudo revelou que existe variabilidade entre e dentro das espécies de Dimorphandra spp., o qual formou quatro grupos. Apesar da variabilidade genética constatada, as expedições de coleta demonstraram que a maioria das áreas amostradas está sujeita a perdas de recursos genéticos de fava-d'anta devido aos seguintes fatores: ocorrência de ação antrópica contínua; propensão a incêndios naturais; e diminuição dos dispersores naturais de sementes (grandes mamíferos frugíveros). Assim, a proteção destas áreas e a conservação ex situ, são primordiais para manutenção da variabilidade genética dessas espécies.

Genetic divergence among Dimorphandra spp. accessions using RAPD markers

The genus Dimorphandra has distinguish relevance considering either medicinal or biodiversity aspects because it includes two species that are economically important flavonoids sources for pharmachemical industry (D. mollis Benth. and D. gardneriana Tul.), and species endemic to Brazil, such as D. jorgei Silva and D. wilsonii Rizz., threatened by extinction. In order to evaluate variability among accessions of D. mollis (fava-d'anta), D. gardneriana and D. wilsonii, it was collected fruit from individual plants from three Brazilian states in a total of 57 accessions, which were analyzed with RAPD markers. It was used 20 seeds per progeny; the DNA was extracted from fully-formed young leaves, which were collected in bulk. The data were analyzed using a binary matrix, in which the score one represented presence of a band and zero, absence. The similarity matrix was developed by using the arithmetic complement of the Jaccard index, later grouped based on the Neighbor Joining algorithm. It was found considerable intra and inter specific variability in Dimorphandra spp., which were separated into four groups. Though genetic variability was found, the collecting trips showed that most of these areas are subject to loss of genetic resources of fava-d'anta due to the following factors: continuous anthropic activity, propensity for natural fires, and loss of natural seed dispersers (large fruit-eating mammals). Therefore, protections of these areas and ex situ conservation are essentials for the maintenance of genetic variability of these species.

O gênero Dimorphandra tem grande relevância, sobretudo nos aspectos medicinais e de biodiversidade, por incluir duas espécies que são importantes economicamente como fontes de flavonoides para indústria farmacoquímica (D. mollis Benth. e D. gardneriana Tull.), e espécies endêmicas do Brasil, como a D. jorgei Silva e D. wilsonii Rizz., sendo esta ameaçada de extinção. Objetivando avaliar a variabilidade entre acessos de D. mollis, D. gardneriana e D. wilsonii, foram realizadas coletas de frutos separados por planta em três estados brasileiros em um total de 57 acessos que foram analisados por meio da técnica RAPD. Utilizaram-se vinte sementes por progênie e o DNA, extraído de folhas definitivas, jovens, e coletadas em bulk. Os dados foram analisados utilizando-se uma matriz de dados binários. Para formação da matriz de dissimilaridade, foi utilizado o complemento aritmético do Índice de Jaccard e posteriormente o agrupamento pelo algoritmo de Neighbor Joining. O estudo revelou que existe variabilidade entre e dentro das espécies de Dimorphandra spp., o qual formou quatro grupos. Apesar da variabilidade genética constatada, as expedições de coleta demonstraram que a maioria das áreas amostradas está sujeita a perdas de recursos genéticos de fava-d'anta devido aos seguintes fatores: ocorrência de ação antrópica contínua; propensão a incêndios naturais; e diminuição dos dispersores naturais de sementes (grandes mamíferos frugíveros). Assim, a proteção destas áreas e a conservação ex situ, são primordiais para manutenção da variabilidade genética dessas espécies.

Genetic divergence among Dimorphandra spp. accessions using RAPD markers

The genus Dimorphandra has distinguish relevance considering either medicinal or biodiversity aspects because it includes two species that are economically important flavonoids sources for pharmachemical industry (D. mollis Benth. and D. gardneriana Tul.), and species endemic to Brazil, such as D. jorgei Silva and D. wilsonii Rizz., threatened by extinction. In order to evaluate variability among accessions of D. mollis (fava-d'anta), D. gardneriana and D. wilsonii, it was collected fruit from individual plants from three Brazilian states in a total of 57 accessions, which were analyzed with RAPD markers. It was used 20 seeds per progeny; the DNA was extracted from fully-formed young leaves, which were collected in bulk. The data were analyzed using a binary matrix, in which the score one represented presence of a band and zero, absence. The similarity matrix was developed by using the arithmetic complement of the Jaccard index, later grouped based on the Neighbor Joining algorithm. It was found considerable intra and inter specific variability in Dimorphandra spp., which were separated into four groups. Though genetic variability was found, the collecting trips showed that most of these areas are subject to loss of genetic resources of fava-d'anta due to the following factors: continuous anthropic activity, propensity for natural fires, and loss of natural seed dispersers (large fruit-eating mammals). Therefore, protections of these areas and ex situ conservation are essentials for the maintenance of genetic variability of these species.

O gênero Dimorphandra tem grande relevância, sobretudo nos aspectos medicinais e de biodiversidade, por incluir duas espécies que são importantes economicamente como fontes de flavonoides para indústria farmacoquímica (D. mollis Benth. e D. gardneriana Tull.), e espécies endêmicas do Brasil, como a D. jorgei Silva e D. wilsonii Rizz., sendo esta ameaçada de extinção. Objetivando avaliar a variabilidade entre acessos de D. mollis, D. gardneriana e D. wilsonii, foram realizadas coletas de frutos separados por planta em três estados brasileiros em um total de 57 acessos que foram analisados por meio da técnica RAPD. Utilizaram-se vinte sementes por progênie e o DNA, extraído de folhas definitivas, jovens, e coletadas em bulk. Os dados foram analisados utilizando-se uma matriz de dados binários. Para formação da matriz de dissimilaridade, foi utilizado o complemento aritmético do Índice de Jaccard e posteriormente o agrupamento pelo algoritmo de Neighbor Joining. O estudo revelou que existe variabilidade entre e dentro das espécies de Dimorphandra spp., o qual formou quatro grupos. Apesar da variabilidade genética constatada, as expedições de coleta demonstraram que a maioria das áreas amostradas está sujeita a perdas de recursos genéticos de fava-d'anta devido aos seguintes fatores: ocorrência de ação antrópica contínua; propensão a incêndios naturais; e diminuição dos dispersores naturais de sementes (grandes mamíferos frugíveros). Assim, a proteção destas áreas e a conservação ex situ, são primordiais para manutenção da variabilidade genética dessas espécies.