Showing papers by "Claudete Aparecida Mangolin published in 2013"

A collection of popcorn as a reservoir of genes for the generation of lineages.

Abstract: In the present study, we analyze the genetic structure and diversity among accessions of popcorn obtained from the CIMMYT International Maize and Wheat Improvement Center that represent the diversity available for current use by breeding programs. The main objectives were to identify SSR loci that were the best indicators of genetic diversity, to measure the genetic diversity within popcorn genotypes, and to analyze the genetic structure of the promising populations destined for use in breeding programs. The mean gene diversity of all SSR loci was 0.6352. An extremely high population differentiation level was detected (Fst = 0.3152) with Fst for each locus ranging from 0.1125 (Umc1229) to 0.4870 (Umc1755). Analyzing the genetic structure of eight popcorn accessions was especially important for identifying both SSR loci with high levels of heterozygosity and genotypes showing high heterozygosity (Boya462 and Arzm13 050). This analysis should be the medium and long-term selection goal for the generation of inbred lines and the future production of new cultivars. Plant accessions Arzm05 083, Arzm13 050, and Urug298 may also be useful varieties that exhibit important agronomic characteristics that can be used through crosses to broaden the genetic basis of popcorn.

Molecular characterization of endophytes isolated from Saccharum spp based on esterase and ribosomal DNA (ITS1-5.8S-ITS2) analyses.

Abstract: This study used esterases and ribosomal DNA (rDNA) markers to determine endophytic variability in order to better understand endophyte-host interactions. Polyacrylamide gel electrophoresis and esterase isoenzymes (EST; EC 3.1.1.3), with α-naphthyl acetate and β-naphthyl acetate as substrates, were used to assess relationships among endophytes. ITS1-5.8S-ITS2 sequencing data were used as rDNA markers. Thirty-two esterases were obtained from 37 isolates of Saccharum spp, which clustered into five endophyte groups. Esterase EST-06 was observed with the highest frequency, being present in 22 of the 37 isolates analyzed, followed by esterase EST-11, which was present in 20 isolates. The esterases EST-10 and EST-14 were present in 19 isolates and EST-09 was present in 18 isolates. The esterase EST-01 was unique to isolate 33 and can, therefore, be used as a marker for this isolate. None of the esterases identified were common to all isolates tested. Similarly, phylogenetic analysis, based on rDNA sequence data, classified the isolates into 5 genus groups: 1) Curvularia with a 100% bootstrap value (BP), 2) Alternaria with 100% BP, 3) Epicoccum with 60% BP, 4) Phoma with 89% BP, and 5) Saccharicola with 100% BP. This polyphyletic analysis based on several markers, therefore, proved to be a valuable approach in determining the relationship between variation in endophytes and their associated host plants. Furthermore, both the esterase and rDNA analyses obtained similar results and were equally effective in resolving relationships.

Redução de chalconas utilizando cultura de células de Cereus peruvianus

Abstract: Cereus peruvianus e um cacto conhecido como “mandacaru” e que produz varios compostos de interesse economico, farmacologico e industrial. Os tecidos de calos foram mantidos em meio solido ate serem transferidos para frascos de cultura contendo a substância a ser biotransformada e tampao fosfato pH 7,0 sendo mantidos em agitador orbital. Atualmente os quimicos orgânicos sinteticos tem utilizado reacoes enzimaticas na sintese de intermediarios enantiomericamente puros para preparar moleculas opticamente ativas de interesse farmacologico, agroquimico e alimenticio. O objetivo do presente estudo foi reduzir chalconas, utilizadas como substratos nas reacoes de biocatalise, utilizando celulas de tecidos de calos de C. peruvianus. Esta cultura de celulas apresentou a capacidade de reducao regiosseletiva das enonas avaliadas. A partir destes resultados, pode-se concluir que as celulas utilizadas na biocatalise expressam enzimas do tipo redutase podendo entao atuar como biocatalisadores em reacoes orgânicas de reducao de duplas ligacoes.

Genética de poplaciones de Atta sexdens rubropilosa (Hymenoptera: Formicidae)

Abstract: The genetic variability of Atta sexdens rubropilosa leaf-cutting ants collected from five brazilian localities was evaluated with PCR-RAPD technique. We used 15 primers producing 148 fragments of which 123 (83.11 %) contained polymorphisms. The estimated Shannon index was 0.3836 ± 0.2335 showing that these ants possess high genetic diversity. The G ST value was 0.2372 and ΦPT = 0.184, indicating that the analyzed populations are moderately differentiated and 82 % of the variation obtained occur within populations. Although Mantel’s test had shown correlation between genetic distances and geographic was observed that Ivatuba and Itambe (33.8 km) have the small geographical distance and the largest genetic distance. The lower genetic distance was estimated for Maringa and Ivatuba but this localities have a small geographic distance (42.3 km), indicating that there are no barriers for mating among reproducers in these populations. The high degree of polymorphism (83.11 %) and the ability to cross among the populations in the studied regions indicate that this species of leaf-cutting ant is well adapted to the region; therefore, integrated control programs can be developed.

Genetic diversity analysis of Capsicum spp germplasm bank accessions based on α/β-esterase polymorphism.

Abstract: Genetic diversity and structure were analyzed in 10 accessions belonging to Banco Ativo de Germoplasma de Capsicum located at Federal University of Piaui in northwestern Brazil that receives pepper samples grown in community gardens in various regions and Brazilian states. Selections were made from seeds of C. chinense (4 accessions), C. annuum (5 accessions), and C. baccatum (1 accession). Samples consisting of leaves were collected from 4-10 plants of each accession (a total of 85 plants). Native polyacrylamide gel electrophoresis was used to identify α- and β-esterase polymorphisms. Polymorphism was clearly detected in 5 loci. Sixteen alleles were found at 5 α/β-esterase loci of the three Capsicum species. In the C. chinense samples, the highest HO and HE values were 0.3625 and 0.4395, respectively, whereas in C. annuum samples, HO and HE values were 0.2980 and 0.3310, respectively; the estimated HO and HE values in C. chinense samples were higher than those detected in C. annuum samples. A deficit of homozygous individuals was found in C. chinense (FIS = -0.6978) and C. annuum (FIS = 0.7750). Genetic differentiation between C. chinense and C. annuum at these loci was high (FST = 0.1867) indicating that C. chinense and C. annuum are genetically structured species for α/β- esterase isozymes. The esterase analysis showed high genetic diversity among the C. chinense and C. annuum samples and very high genetic differentiation (FST = 0.6321) among the C. chinense and C. annuum samples and the C. baccatum accession.

POPULATION GENETICS OF Atta sexdens rubropilosa (HYMENOPTERA: FORMICIDAE)

Abstract: The genetic variability of Atta sexdens rubropilosa leaf-cutting ants collected from five brazilian localities was evaluated with PCR-RAPD technique. We used 15 primers producing 148 fragments of which 123 (83,11 %) contained polymorphisms. The estimated Shannon index was 0.3836 ± 0.2335 showing that these ants possess high genetic diversity. The GST value was 0,2372 and PT = 0,184, indicating that the analyzed populations are moderately differentiated and 82 % of the variation obtained occur within populations. Although Mantel’s test had shown correlation between genetic distances and geographic was observed that Ivatuba and Itambe (33,8 km) have the small geographical distance and the largest genetic distance. The lower genetic distance was estimated for Maringa and Ivatuba but this localities have a small geographic distance (42,3 km), indicating that there are no barriers for mating among reproducers in these populations. The high degree of polymorphism (83,11 %) and the ability to cross among the populations in the studied regions indicate that this species of leaf-cutting ant is well adapted to the region; therefore, integrated control programs can be developed.