Development And Characterization Of Microsatellite Loci For Tabebuia Cassinoides (bignoniaceae).

Tabebuia cassinoides (Lam.) DC., popularly known as caxeta, is a tree species that belongs to the plant family Bignoniaceae. This species is endemic to the Brazilian Atlantic Forest and is widely exploited commercially. To date, little is known about its genetic structure, preventing the establishment of adequate management plans for this taxon. The objective of this study was to construct a microsatellite-enriched genomic library for T. cassinoides to select polymorphic loci, and standardize polymerase chain reaction amplification conditions. Of the 15 loci examined, 5 were polymorphic. The number of alleles per locus ranged from 2 to 8, with a mean of 4.4. The microsatellite loci described here represent the basis for detailed population genetic studies of this species, which will greatly contribute for the development of better conservation strategies for this taxon.135601-

Development and characterization of microsatellite loci for Tabebuia cassinoides (Bignoniaceae)

Tabebuia cassinoides (Lam.) DC., popularly known as caxeta, is a tree species that belongs to the plant family Bignoniaceae. This species is endemic to the Brazilian Atlantic Forest and is widely exploited commercially. To date, little is known about its genetic structure, preventing the establishment of adequate management plans for this taxon. The objective of this study was to construct a microsatellite-enriched genomic library for T. cassinoides to select polymorphic loci, and standardize polymerase chain reaction amplification conditions. Of the 15 loci examined, 5 were polymorphic. The number of alleles per locus ranged from 2 to 8, with a mean of 4.4. The microsatellite loci described here represent the basis for detailed population genetic studies of this species, which will greatly contribute for the development of better conservation strategies for this taxon. Tabebuia cassinoides (Lam.) DC., popularly known as caxeta, is a tree species that belongs to the plant family Bignoniaceae. This species is endemic to the Brazilian Atlantic Forest and is widely exploited commercially. To date, little is known about its genetic structure, preventing the establishment of adequate management plans for this taxon. The objective of this study was to construct a microsatellite-enriched genomic library for T. cassinoides to select polymorphic loci, and standardize polymerase chain reaction amplification conditions. Of the 15 loci examined, 5 were polymorphic. The number of alleles per locus ranged from 2 to 8, with a mean of 4.4. The microsatellite loci described here represent the basis for detailed population genetic studies of this species, which will greatly contribute for the development of better conservation strategies for this taxon13356015605CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP142040/2009-6; 305102/2010-9sem informação2010/20548-

Genetic diversity analysis among pigeonpea genotypes adapted to South American regions based on microsatellite markers.

The pigeonpea [Cajanus cajan (L) Millspaugh] is one of the most important perennial legume crops utilized in the food, fodder, soil conservation, crop-livestock integrated systems, reclaiming of degraded pastures and symbiotic nitrogen fixation. Microsatellite markers were used to estimate the genetic diversity of 77 pigeonpea genotypes selected from the germplasm collections at Embrapa Cattle-Southeast and, to evaluate their transferability to Phaseolus vulgaris and Vigna unguiculata species. The number of alleles per locus ranged from 2 to12, with an average of 5.1 alleles. The PIC values ranged from 0.11 to 0.80 (average 0.49) and the D values from 0.23 to 0.91 (average 0.58). The averages of observed and expected heterozygosity were 0.25 and 0.47, respectively, showing a deficit in heterozygosity. A model-based Bayesian approach implemented in the software STRUCTURE was used to assign genotypes into clusters. A dendrogram was constructed based on the modified Roger's genetic distances using a neighbor-joining method (NJ). A total of four clusters were assembled by STRUCTURE and a strong tendency of correspondence between the Bayesian clusters in the NJ tree was observed. The genetic distance ranged from 0.09 to 0.62 (average 0.37), showing a low genetic diversity in the pigeonpea genotypes. Transferability of pigeonpea-specific microsatellites revealed a cross-amplification and the presence of polymorphic alleles in P. vulgaris and V. unguiculata

Caracterização molecular do banco de germoplasma de Panicum maximum Jacq.

Panicum maximum Jacq. está entre as principais forrageiras cultivadas no Brasil. Ocupa uma posição de destaque, por apresentar elevada produção e qualidade, ser de fácil propagação por sementes e altamente palatável ao gado. Por causa da importância e do potencial desta espécie, nosso objetivo foi acessar a diversidade genética do germoplasma de P. maximum, por meio de marcadores microssatélites, visando gerar informações que poderão auxiliar nos programas de melhoramento, reduzindo o custo e o tempo de lançamento de novos cultivares

Development of microsatellite markers in Guineagrass (Panicum maximum Jacq.) and their transferability to other tropical forage grass species.

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

Inheritance of growth habit detected by genetic linkage analysis using microsatellites in the common bean (Phaseolus vulgaris L.).

The genetic linkage map for the common bean (Phaseolus vulgaris L.) is a valuable tool for breeding programs. Breeders provide new cultivars that meet the requirements of farmers and consumers, such as seed color, seed size, maturity, and growth habit. A genetic study was conducted to examine the genetics behind certain qualitative traits. Growth habit is usually described as a recessive trait inherited by a single gene, and there is no consensus about the position of the locus. The aim of this study was to develop a new genetic linkage map using genic and genomic microsatellite markers and three morphological traits: growth habit, flower color, and pod tip shape. A mapping population consisting of 380 recombinant F10 lines was generated from IAC-UNA × CAL143. A total of 871 microsatellites were screened for polymorphisms among the parents, and a linkage map was obtained with 198 mapped microsatellites. The total map length was 1865.9 cM, and the average distance between markers was 9.4 cM. Flower color and pod tip shape were mapped and segregated at Mendelian ratios, as expected. The segregation ratio and linkage data analyses indicated that the determinacy growth habit was inherited as two independent and dominant genes, and a genetic model is proposed for this trait

Molecular characterization of genotypes selected from the germplasm bank of Cajanus cajan (L.) millsp and cross-species amplification in three legume species.

Cajanus cajan (L.) Millsp (2n = 22) is one of the important grain legume crops in the tropics and subtropics. The centre of diversity is in India (SMARTT, 1990), which accounts for more than 80% of the world?s C. cajan production. Its seed is primarily consumed as dhal (dried dehusked split cotyledons) and in Latin America the tender green seeds are used as canned peas. This specie has wide adaptability to diverse climates and soils. Because of its multiple uses as food, fodder, fuel wood, rearing lac insects, hedges, windbreaks, soil conservation, roof thatches and green manure, it plays an important role in subsistence agriculture. However, the average world productivity of C. cajan is rather low (709 kg ha -1) (FAO, 2004), indicating an urgent need for improving the genetic potential of the crop. Microsatellite markers are of high interest in C. cajan breeding programs. They are quite effective to estimate genetic diversity and genetic relationships, as well as to predict the genetic value of selected candidates derived from intraspecific crosses and the performance of their hybrid progenies. Microsatellite markers are short tandem repeat sequence motifs consisting of repeat units of 1-6 base pairs (bp). They are highly polymorphic DNA markers with discrete loci and co-dominant alleles (TAUTZ and SCHLOTTERER, 1994). The present study reports the characterization of 67 microsatellite markers for investigated a genetic diversity de C. cajan and cross-species amplification in other legume species

Genetic diversity analysis among pigeonpea genotypes adapted to South American regions based on microsatellite markers.

The pigeonpea [Cajanus cajan (L) Millspaugh] is one of the most important perennial legume crops utilized in the food, fodder, soil conservation, crop-livestock integrated systems, reclaiming of degraded pastures and symbiotic nitrogen fixation. Microsatellite markers were used to estimate the genetic diversity of 77 pigeonpea genotypes selected from the germplasm collections at Embrapa Cattle-Southeast and, to evaluate their transferability to Phaseolus vulgaris and Vigna unguiculata species. The number of alleles per locus ranged from 2 to12, with an average of 5.1 alleles. The PIC values ranged from 0.11 to 0.80 (average 0.49) and the D values from 0.23 to 0.91 (average 0.58). The averages of observed and expected heterozygosity were 0.25 and 0.47, respectively, showing a deficit in heterozygosity. A model-based Bayesian approach implemented in the software STRUCTURE was used to assign genotypes into clusters. A dendrogram was constructed based on the modified Roger?s genetic distances using a neighbor-joining method (NJ). A total of four clusters were assembled by STRUCTURE and a strong tendency of correspondence between the Bayesian clusters in the NJ tree was observed. The genetic distance ranged from 0.09 to 0.62 (average 0.37), showing a low genetic diversity in the pigeonpea genotypes. Transferability of pigeonpea-specific microsatellites revealed a cross-amplification and the presence of polymorphic alleles in P. vulgaris and V. unguiculata.201

Microsatellite loci for an endemic stingless bee Melipona seminigra merrillae (Apidae, meliponini) from Amazon

Melipona seminigra merrillae is one of the main pollinators of Central Amazon native flora. These stingless bees are reared as economic alternative and for forest conservation purposes. Nine polymorphic microsatellite markers were characterized in 44 genotypes of M. seminigra merrillae from the Meliponary of the Instituto Nacional de Pesquisas da Amazonia, INPA (3° 05.838′S 059° 59.103′W), Manaus, Brazil. The number of alleles observed for each locus ranged from 3 to 8, with an average of 3.7 alleles per locus. The polymorphism information content (PIC) varied between 0.21 and 0.81 (average 0.50) and the discriminating power (D) ranged from 0.59 to 0.98 (average 0.77). The observed heterozygosity (H o) and the expected heterozygosity (H e) were 0.04-0.68 and 0.19-0.84, respectively. A cross-amplification test in three Melipona species suggested potential transferability of these microsatellites. These microsatellite markers should be useful for characterizing natural populations and specie conservation. © Springer Science+Business Media B.V. 2009