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One of the most important functions of forests is their capacity to store carbon, which varies according to floristic composition, age, and tree density. To provide information that is useful for the carbon inventories, the construction of growth curves for dominant strata within the study area was set as the objective of this work. With data from the National Forest and Soil Inventory 2005-2009 were calculated the IVI by conglomerate and from a dendrogram performed with cluster analysis, using the Ward's linkage method, dominant strata were formed. A growth curve per community was constructed based on the maximum yields per hectare recorded in the forestry management plans, the percentage increases were attributed to volume per species at different ages, which was obtained by ICA through trunk analysis. Five dominant strata were formed; Pinus oocarpa (21.08 % to 54.38 %), Pinus douglasiana (41.45 % to 89.83 %), Pinus devoniana (27.53 % to 63.88 %), Pinus leiophylla (27.53 % to 89.03 %) and Quercus spp. (36.05 % to 93.26 %). The maximum yields for the stands within the study area were 329.98 m3 ha-1, 330.71 m3 ha-1, 171.35 m3 ha-1, 185.22 % and 127. 46 m3 ha-1, respectively. The Pinus oocarpa and Pinus douglasiana dominant strata are had the highest percentage increases in the region due to their historical foment. [ABSTRACT FROM AUTHOR]

Endophytic microorganisms are those that inhabit the interior of plant tissues and organs without causing damage to the plant, triggering a mutualistic interaction. These endophytes are known to produce compounds with various applications in the areas of biotechnology, pharmaceutical industry and agriculture; therefore, molecular methods are used to investigate the phylogeny of these organisms. The Brazilian Cerrado is the second largest biome in Brazil and is considered a hotspot, with a high diversity of endemic fauna and flora. The objective of this work was to analyze, through in silico analysis, the phylogeny of cultivable endophytic fungi isolated from plants found in the Brazilian Cerrado biome. A search was carried out for articles that worked with endophytes in the period between 2012 and 2022. The dendrogram was generated using the Neighbor-joining method based on the ITS1-5.8S-ITS2 conserved region obtained by GenBank codes of isolated endophytes. The genera Xylaria, Diaporthe, and Colletotrichum were isolated in more than three plants in the seven articles found. Most of the articles found related to the biodiversity of endophytic fungi from the Brazilian Cerrado aim at the bioprospecting of bioactive compounds, through culture-dependent methods; as such, a part of endophytic diversity may be lost due to the inability of certain endophytes to grow in artificial media. In silico analysis can assist in the investigation of phylogenetic relationships between endophytic fungi and has the potential to guide future work aimed at prospecting for bioactive compounds, phylogenetic identification, or biodiversity of this group of endophytes. [ABSTRACT FROM AUTHOR]

Microsatellites were used to evaluate and compare the lineage relationships and genetic diversity of two improved cultivars of corn (Zea mays L.), seven modern native races, and eight archaeological Chimú samples (1.100-1.500 AD) of the North Peruvian coast. Electrophoresis was required to remove the PCR inhibitors from ancient DNA. Eight STR primer pairs generated amplicons from the genome of modern corn, but only five amplified ancient corn DNA. To establish the lineage relationships among samples, the coefficient of similarity of Jaccard and the technique of analysis of conglomerate with binding average were used. Thus, the pattern of genealogical and genetic relationships of the genotypes were determined. Seven out of the eight pairs of SSR primers revealed polymorphism, being 2.47 (range 2-6) the average of polymorphic alleles. The total alleles tested were 23, with 97 polymorphic bands for the modern corn, yet being monomorphic for the Chimú corn, generating an average of genetic similarity of 0.44 and 1, respectively. These results suggest the existence of inbreeding in some populations of Chimú corn of the north coast of Peru 500 to 900 years ago. Modern races exhibited higher polymorphism, due to hybridization and better assisted selection, in agreement with cytogenetic data. [ABSTRACT FROM AUTHOR]

Which came first, the chicken or the egg? That is not a pun, joking or irrelevant question. Two hypotheses have tried to answer it. The first, and accepted for years, proposes that the evolutionary process went from oviparity, through an Embryonic Retention (ER) phase, to viviparity. In other words, the simpler egg came first, which hatched into the more complex chicken. That is known as the terrestrial model. Indeed, fishes typically lay eggs, albeit some sharks are viviparous. Even some living (extant) mammals are oviparous, (monotremes like platypus and echidnas). But new evidence has challenged such traditional view, proposing that it was the other way round. Thus, first came the chicken, which eventually laid the egg. That is the Extended Embryo-Retention (EER) model. In the first evolutionary step of this scenario, ancient reptiles, birds and mammals gave birth to offspring. Subsequently, some of them developed oviparity. Indeed, several archaeological and phylogenetic discoveries have shown that first, during the ER period, thin layers of tissues (extraembryonic membranes) evolved for a better development of the embryo, given rise to the amniotes. It is known that living reptiles (like crocodiles and turtles) and birds typically show non-EER oviparity. But curiously, most lizards, snakes and mammals exhibit oviparity with EER or viviparity. While the debate continues, both archaeology and molecular biology will contribute to clarify this interesting topic. [ABSTRACT FROM AUTHOR]

Which came first, the chicken or the egg? That is not a pun, joking or irrelevant question. Two hypotheses have tried to answer it. The first, and accepted for years, proposes that the evolutionary process went from oviparity, through an Embryonic Retention (ER) phase, to viviparity. In other words, the simpler egg came first, which hatched into the more complex chicken. That is known as the terrestrial model. Indeed, fishes typically lay eggs, albeit some sharks are viviparous. Even some living (extant) mammals are oviparous, (monotremes like platypus and echidnas). But new evidence has challenged such traditional view, proposing that it was the other way round. Thus, first came the chicken, which eventually laid the egg. That is the Extended Embryo-Retention (EER) model. In the first evolutionary step of this scenario, ancient reptiles, birds and mammals gave birth to offspring. Subsequently, some of them developed oviparity. Indeed, several archaeological and phylogenetic discoveries have shown that first, during the ER period, thin layers of tissues (extraembryonic membranes) evolved for a better development of the embryo, given rise to the amniotes. It is known that living reptiles (like crocodiles and turtles) and birds typically show non-EER oviparity. But curiously, most lizards, snakes and mammals exhibit oviparity with EER or viviparity. While the debate continues, both archaeology and molecular biology will contribute to clarify this interesting topic. [ABSTRACT FROM AUTHOR]

Microsatellites were used to evaluate and compare the lineage relationships and genetic diversity of two improved cultivars of corn (Zea mays L.), seven modern native races, and eight archaeological Chimú samples (1.100-1.500 AD) of the North Peruvian coast. Electrophoresis was required to remove the PCR inhibitors from ancient DNA. Eight STR primer pairs generated amplicons from the genome of modern corn, but only five amplified ancient corn DNA. To establish the lineage relationships among samples, the coefficient of similarity of Jaccard and the technique of analysis of conglomerate with binding average were used. Thus, the pattern of genealogical and genetic relationships of the genotypes were determined. Seven out of the eight pairs of SSR primers revealed polymorphism, being 2.47 (range 2-6) the average of polymorphic alleles. The total alleles tested were 23, with 97 polymorphic bands for the modern corn, yet being monomorphic for the Chimú corn, generating an average of genetic similarity of 0.44 and 1, respectively. These results suggest the existence of inbreeding in some populations of Chimú corn of the north coast of Peru 500 to 900 years ago. Modern races exhibited higher polymorphism, due to hybridization and better assisted selection, in agreement with cytogenetic data. [ABSTRACT FROM AUTHOR]

Trichoderma spp., perteneciente a las especies fúngicas del suelo, son usadas ampliamente en la agricultura, debido a sus múltiples beneficios, en especial al ser antagonista de plagas y enfermedades que presentan los cultivos. El objetivo del presente trabajo fue seleccionar, caracterizar, identificar, propagar y conservar hongos benéficos del suelo. El estudio se desarrolló en la Finca Nueva Era en la vía la Primavera, sector La Iberia, perteneciente al Cantón El Guabo de la provincia de El Oro, Ecuador. Se identificaron varias especies de Trichodermas tales como: T. asperellum, T. theobromicola, T. spirales, T. reesei, T. melanomagna, T. harzianum, T. viride. Empleando como variables 12 descriptores, que caracterizan a las especies mediante la observación macro y microscópica de las accesiones, los factores más discriminantes fueron número de anillos, ancho del primer anillo y longitud del septo (Nani, AA1, LSep, R5D), el ANOVA presento significancia para estos descriptores y en el análisis de componentes principales fueron los que permitieron acumular la mayor varianza. El análisis de conglomerados jerárquicos arrojó un dendrograma que permite la identificación de 4 grupos bien definidos: G1 (T. asper (1-6); T. theob (1-2); T. spir (1-3); T. rees (1-2)); G2 (T. rees 3; T. melan); G3 (T. harz); G4 (T. viride). La diversidad encontrada de Trichodermas spp., nos demuestra que podemos tener suelos con una microbiota benéfica muy importante si realizamos un buen manejo de este recurso en la producción bananera.

En el presente trabajo se muestran los resultados de la evaluación de 129 árboles de cacao (Theobroma cacao, L.) que forman parte del jardín clonal de la UTMACH en la granja Santa Inés perteneciente a la Facultad de Ciencias Agropecuarias; con la finalidad de conocer su riqueza genética y el potencial agronómico de interés, que puede estar contenido en dicha población, mediante un análisis morfológico y estadístico que permita generar información sobre las accesiones en estudio. Se realizó una toma de datos entre los meses de junio y enero, de un total de 46 variables respecto a tres partes vegetativas, flores, fruto y semilla Los datos obtenidos fueron organizados y se efectuó un análisis estadístico mediante el SPSS, dando como resultado un cubo de componentes principales y un dendrograma que utiliza distancias Euclidianas para formar agrupaciones. En el análisis de componentes principales se determinó 17 variables responsables de 70,33% de variabilidad para las accesiones de estudio. La información generada da paso a la conservación de material genético único y de suma importancia en futuros proyectos de fitomejoramiento, encaminados a la obtención de cultivares con características agronómicas que garanticen el futuro de la producción de cacao en el Ecuador y la provincia, El Oro.

Copyright of Revista Mexicana de Ciencias Agrícolas is the property of Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agronomía Colombiana is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Six simultaneous experiments were carried out to determine the content of primary and secondary metabolites of six species of trees, shrubs and forage herbaceous legumes under the edaphoclimatic conditions of Valle del Cauto, Cuba. A randomized block design with six replications was used and the treatments were the regrowth ages of 60, 120 and 180 days for trees and shrubs (Leucaena leucocephala, Tithonia diversifolia, Gliricidia sepium and Eritrina variegata) and 30, 45, 60, 75 and 90 days for creeping legumes (Neonotonia wightii and Teramnus labialis), in the rainy and dry seasons. There were determined N, glucose, fructose and sucrose (primary); total phenols, total tannins, total condensed tannins, total bound condensed tannins, free condensed tannins, alkaloids, flavonoids, saponins, triterpenes, total steroids, stachyose, verbascose and raffinose. Cluster analyzes to group species with similar characteristics were performed. During the rainy season seven groups were found and in the dry season eight; with the best results, comprehensively, for Gliricidia sepium and Tithonia diversifolia in both seasonal periods. The age had a marked effect on the content of primary and secondary metabolites by decreasing the former and increasing the latter as maturity advanced. This performance was evidenced by verifying, through cluster analysis, that the groups where the highest contents of secondary compounds were found were composed of the most advanced ages of the Neonotonia wightii, Teramnus labialis, Erythrina variegata and Leucaena leucocephala species, in both seasonal periods. Aspects of vital importance for future studies where the associative effects of species with lower content of these compounds (Tithonia diversifolia and Gliricidia sepium) were are analyzed, both in the ecosystem and in the animal response. [ABSTRACT FROM AUTHOR]

El análisis de contenido jerárquico ponderado (ACJP) integra criterios y procedimientos de diversas tradiciones de análisis de datos cualitativos, siendo los más relevantes: el análisis en progreso (Taylor & Bogdan, 1985), el método de comparaciones constantes (Glaser & Strauss, 1967; Strauss & Corbin, 1997), el análisis etnográfico secuencial (Spradley, 1979) y el análisis estadístico del contenido manifiesto (Krippendorff, 1990).

The documentation of the Neotropical species of the Arecaceae family, based on the recent contributions to its taxonomy and its relationship with natural landscapes, updates the spatial patterns to which they adapt in their range of distribution. In this case 121 records of specimens of the 11 species of the genus Attalea of Bolivia and their relationship with 30 ecological systems that approximate their scope of distribution at regional level are released. To this end, the geographical coordinates were systematized, verified and corrected. Localities of all the specimens collected from the genus Attalea in order to compare them with ecological systems, using the ArgGis tools. We then elaborate a dendrogram (species vs. ecological systems) using the minimum distance method in the R program. The analysis of the relation of the species with the ecological systems highlights a species that does not compose to the southwest amazon: A. eichleri and that is native to ecological systems of the Cerrado. Among the SW Amazonian Attalea species, A. blepharopus (endemic to Bolivia) is isolated from the others and the rest subgroup species according to their presence in forests and savannas, in addition to the subandean and alluvial, as it is for A. princeps, which is found in 17 systems (57%). Eight species of Attalea are common with Peru and 10 with Brazil. It is important to relate the hierarchical grouping of the Attalea species with ecological systems in function of landscape dynamics to document their space patterns and also for their conservation.

Copyright of Brazilian Journal of Applied Technology for Agricultural Science / Revista Brasileira de Tecnologia Aplicada nas Ciências Agrárias is the property of Brazilian Journal of Applied Technology for Agricultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The global market has an increasing demand for buffalo by-products due to their unique nutritional characteristics. Many buffalo herds lack suitable breeding control programs, hindering the implementation of selection programs. Objective: To evaluate milk production per lactation (MP), lactation length (LL), and calving interval (CI) of a herd of crossbred Murrah buffaloes to support buffalo clustering according to their potential. Methods: Data from 543 lactations between 2002 and 2014 from 105 crossbred Murrah female buffaloes were used. Data were subjected to principal component analysis (PCA) and cluster analysis. Results: The first components (PCs) were responsible for 92.32% of the total variation, of which 61.45 and 30.87% were explained by the first (PC1) and second (PC2) components, respectively. The cluster analysis allowed three female buffalo groups according to their potentials. Conclusion: Buffalo farmers can make decisions on nutritional, reproductive management and cow culling based on grouping. [ABSTRACT FROM AUTHOR]

In this work, we analyzed the richness and biogeographic relations of Papilionoidea at the Mexican Gulf Biogeographic Province. It applied PAE and Jaccard index at 24 sites and we find 793 species was associated at high evergreen tropical forest (ETF), of which 218 were Exclusives species in this vegetation type and they can used in conservation studies and 86 of these as Restricted with limited distribution in ETF. In this analysis, the studied sites formed two groups, one at north and another at south of the Sierra Chiconquiaco. These groups support the idea of the Mexican Gulf biogeographic province separated in two districts. [ABSTRACT FROM AUTHOR]

Elaeagnus is a Eurasian tree with 77 species worldwide. In this study, ISSR markers were used to establish the level of genetic relationships and polymorphism across nine genotypes of Elaeagnus angustifolia collected from 9 different regions of West Azarbaijan province. The ISSR analysis with 11 anchored primers also generated 116 scorable loci, of which 92 were polymorphic (79.3%). The estimated Jaccard similarity coefficient ranged from 0.44 to 0.76 for the ISSR markers. Cluster analysis was carried out, based on the Unweighted Pair Group Method with Arithmetic Averages (UPGMA) and the dendrogram drawn with the help of the NTSYSpc 2.02 software. The analysis revealed 5 main clusters for the ISSR data. According to our results, there is a relatively high genetic distance across E. angustifolia genotypes in the West Azarbaijan province of Iran. Furthermore, it could be inferred that ISSR markers are suitable tools for the evaluation of genetic diversity and relationships within the Elaeagnus genus.A Elaeagnus é uma árvore da Eurásia com 77 espécies em todo o mundo. Neste estudo, marcadores ISSR foram usados para estabelecer o nível de relações genéticas e polimorfismo entre nove genótipos de Elaeagnus angustifolia, coletados em 9 diferentes regiões da província do Azerbaijão Ocidental. A análise ISSR, com 11 primers ancorados, também gerou 116 loci contáveis, dos quais 92 polimórficos (79,3%). O coeficiente de similaridade de Jaccard estimado, variou de 0,44 a 0,76 para os marcadores ISSR. A análise de agrupamento foi realizada com base no Método não-ponderado de pares não-agrupados, com médias aritméticas (UPGMA), e a dendrograma elaborada com a ajuda do software NTSYSpc 2.02. A análise revelou cinco grupos principais para os dados ISSR. De acordo com nossos resultados, há uma distância genética relativamente alta entre genótipos de E. angustifolia na província de Azarbaijan Ocidental no Iran. Além disso, pode-se inferir que os marcadores ISSR são ferramentas adequadas para a avaliação da diversidade genética e as relações dentro do gênero Elaeagnus.

Se realizó un análisis de clasificación numérica para comparar las semejanzas florístico-geográficas-bioclimáticas de los bosques mesófilos de montaña (BMM) de México. Con base en publicaciones de carácter florístico, de vegetación y sinecológico se obtuvo una base de datos de la flora vascular del BMM que contiene 6 453 especies, 1 426 géneros y 213 familias. La matriz de presencia-ausencia consta de 2 856 especies (180 familias, 897 géneros) distribuidas en 83 localidades; la clasificación se realizó mediante un análisis de conglomerados, utilizando índices de similitud; se agrupó con el método UPGMA y se construyeron dendrogramas. Con BIOCLIM se obtuvo el perfil bioclimático de cada grupo y con el promedio de las variables se generó una matriz que se clasificó como la anterior. La importancia de las variables bioclimáticas fue evaluada mediante un análisis de ordenación por componentes principales. Los grupos florísticamente similares se ajustan a las provincias florísticas de México y los perfiles bioclimáticos respaldan dichas agrupaciones. Por sus características bioclimáticas, los BMM se agrupan en 3 conjuntos de localidades. Se sustenta que las localidades geográficamente más cercanas presentan mayor similitud florística. Conforme se genera más información sobre el BMM de México se refuerzan las hipótesis de relación entre las provincias florísticas.A numerical classification analysis was made to compare the floristic-geographic-bioclimatic resemblance among Mexico's cloud forest (MCF). A MCF vascular flora database was made based on floristics, vegetation and sinecological published work; which contains 6 453 species, 1 426 genera and 213 families. The presence-absence matrix consists of 2 856 species (180 families and 897 genera) scattered through 83 localities; this was rated by means of a conglomerate analysis using the similarity indexes this was put together using the UPGMA method; dendrograms were also made. The bioclimatic profile of each group was obtained using BIOCLIM, the variable average was used to generate a matrix which was rated like the previous one. Based on the order analysis the importance of bioclimatic variables was evaluated through its main component. The floristical similar groups match Mexico's floristic provinces and bioclimatic profiles which back up such groupings. Based on their bioclimatic features the MCF are rated on three groups of localities. It has been noticed that the closer localities are geographically they exhibit greater floristic similarities. Based on the research of the MCF relationships among floristic provinces we reach stronger hypothesis.

O objetivo deste trabalho foi estabelecer padrões alélicos e estimar as distâncias genéticas baseadas em marcador SSR de 44 cultivares de cebola adaptadas às condições de cultivo tropicais e subtropicais do Brasil. Para visualização da similaridade genética, utilizou-se o dendrograma UPGMA gerado da matriz de distâncias do coeficiente de Jaccard, com base em 40 alelos de 13 locos SSR. O DNA total foi extraído pelo método CTAB 2x, e os produtos de PCR foram analisados em géis de poliacrilamida desnaturante 6% e corados com nitrato de prata. O número de pares de bases foi estimado pelo método da mobilidade inversa, com base em regressão de produtos de tamanho conhecido. A média da heterozigosidade dos locos SSR foi 0,58. Os 40 alelos dos 13 locos SSR foram suficientes para distinguir as 44 cultivares de cebola. O maior número de alelos em comum foi observado entre as cultivares Yellow Granex e Henry's Special PRR e o menor, entre as cultivares Baia Periforme Super Precoce e Excel. Os sete grupos principais de cultivares identificados no dendrograma apresentaram concordância com a genealogia conhecida e o tipo agronômico das cultivares avaliadas. Os locos SSR selecionados são adequados para melhoramento e proteção de cultivares da espécie.The objective of this work was to establish allelic patterns and to estimate genetic distances based on the SSR marker in 44 onion cultivars adapted to Brazil's tropical and subtropical growing conditions. An UPGMA dendrogram generated from the distance matrix of the Jaccard's coefficient, based on 40 alleles of 13 SSR loci, was used for visualizing genetic similarities. Total DNA was extracted according to the CTAB 2x protocol, and the PCR products were analyzed in 6% denaturing polyacrylamide gels and stained with silver nitrate. The number of base pairs was estimated by the inverse mobility method, based on regression of products of known size. The heterozygosity mean was 0.58 for all SSR loci. The 40 alleles of the 13 SSR loci were enough to distinguish all 44 onion cultivars. The highest number of common alleles was observed between Yellow Granex and Henry's Special PRR cultivars, and the lowest was observed between the Baia Periforme Super Precoce and Excel cultivars. The seven main groups of onion cultivars identified in the dendrogram were in agreement with the known genetic genealogy and with the agronomic type of the analyzed cultivars. The selected SSR loci are adequate for breeding programs and for protection of the cultivars of the species.

O propósito deste trabalho foi determinar a similaridade genética entre acessos de germoplasma e cultivares comerciais de três espécies de Brachiaria (inter e intraespecífica), por meio de marcadores RAPD. Sementes foram utilizadas como fonte de DNA. 10 “primers” decâmeros foram selecionados de 120 “primers” avaliados, produzindo 107 bandas polimórficas, as quais foram utilizadas para a análise de variância molecular (Amova), o coeficiente de similaridade de Jaccard e índices de fixação gênica. 24,40% da variabilidade genética total estão contidas entre as espécies e 75,60% dentro destas, com índice de fixação gênica (FST) 0,24. No dendrograma, houve a formação de dois ramos, um formado por P. maximum e B. arrecta e o outro subdividido em três: todas amostras de B. ruziziensis; todos os acessos de B. decumbens e três acessos de B. brizantha e o último com dois acessos de B. brizantha mais as B. brizantha comerciais e a B. decumbens cv ‘Basilisk’. Foi possível agrupar os acessos e as cultivares de Brachiaria por meio de RAPD. O índice de variabilidade genética entre espécies foi considerado baixo, sendo inferior a valores determinados em algumas espécies autógamas. B. brizantha apresenta maior variabilidade genética e menor FST indicando maior fluxo gênico intra-específico do que as outras.The aim of this work was to determine intra and intergenetic similarity among three Brachiaria species for germplasm accesses and commercial cultivars using RAPD markers. Seeds were used as DNA source. 10 decamer ‘primers’ were selected among 120 ‘primers’, and 107 polymorphic bands were used to perform the analysis of molecular variance (Amova), Jaccard similarity coefficient and species fixation index. 24.4% of the total variability was contained between species and 75.6% within species, with a species fixation index (FST) of 0.24. The tree showed that two major branches were formed: one with the three outgroup species and another with the species, the latter split into three minor branches: one with all B. ruziziensis samples; another with all B. decumbens accessions and three of B. brizantha; and the last with two B. brizantha accesses, all commercial cultivars and B. decumbens cv. ‘Basilisk’. It was possible to group, through RAPD, Brachiaria accesses and cultivars. The genetic variability index between species was considered low, and somewhat low when compared with autogamous species. B. brizantha showed the highest genetic variability and the lowest FST, which means that there is a higher intra specific genetic flux than the others.

O objetivo deste trabalho foi avaliar a distribuição da variabilidade genética do umbuzeiro (Spondias tuberosa), no Semi-Árido brasileiro, por meio de marcadores AFLP, para subsidiar estratégias de prospecção e conservação da espécie. Foram analisados 68 indivíduos de umbuzeiro de 15 ecorregiões, pelo dendrograma UPGMA e pela dispersão em escala multidimensional (MDS), com o coeficiente de Jaccard de 141 bandas polimórficas de AFLP. A análise da variância molecular foi realizada pela decomposição total entre e dentro das regiões ecogeográficas. O dendrograma apresentou valor cofenético de 0,96, e o gráfico MDS apresentou 0,25 para a falta de ajustamento. A variabilidade genética do umbuzeiro foi estimada em 0,3138, o que indica grande variação entre os grupos de indivíduos. Agrupamentos específicos foram observados em seis regiões ecogeográficas, enquanto nas demais regiões observaram-se pares entre alguns indivíduos, sem formação de agrupamentos específicos por local de amostragem, o que indica que a variabilidade genética do umbuzeironão está uniformemente distribuída no Semi-Árido. Sugerem-se estratégias para o estabelecimento de maior número de áreas para conservação in situ ou amostragens de menor número de indivíduos, em várias unidades de paisagens, para conservação ex situ da variabilidade genética do umbuzeiro.The objective of this work was to evaluate the genetic variability distribution of umbu tree (Spondias tuberosa), within Brazilian Semi-Arid region, based on AFLP markers, in order to suggest prospecting and preservation strategies for this species. Sixty-eight umbu trees of 15 ecogeographic regions were analyzed for 141 polymorphic AFLP bands, through the UPGMA dendrogram and the multidimensional scaling (MDS), based on Jaccard's coefficient . Analysis of molecular variance was accomplished by total decomposition among and within ecogeographic regions. The dendrogram presented co-phenetic value of 0.96, while the MDS presented 0.25 for the badness-of-fit. Umbu genetic variability was estimated in 0.3138, indicating a large variance among individual groups. Specific clusters were observed in six ecogeographic regions, and some individual pairs were observed in the other regions, with no specific clustering by sampling place, which indicates that the genetic variability of umbu tree is not uniformly distributed within Brazilian Semi-Arid. Strategies are suggested to set a larger number of protection areas for in situ conservation, or a smaller number of umbu individuals sampled, in various ecoregion units, for ex situ genetic variability conservation of this species.

Extracts from young leaves of nine sweet cherry (Prunus avium L.) and eight sour cherry (Prunus cerasus L.) varieties, located in the germplasm collection of the 'Direção Regional de Agricultura da Beira Interior' (Fundão, Portugal), were analysed for five isozyme systems in order to characterise these varieties and detect problems of synonymies and homonymies that frequently present. The sweet and sour cherry varieties analyzed showed low isoenzymatic polymorphism, being PGM and PGI the systems with the highest discrimination power. These systems presented seven and five different zymogrames, respectively. IDH showed four patterns. SKDH and 6-PGD grouped the varieties only into two patterns. The evident and discriminant restrictions of this type of analysis had got results that have only been a complement for agronomical and morphological characterization.Nove extratos de folhas com desenvolvimento encompleto foram obtidos de 9 variedades de cerejeira (Prunus avium L.) e 8 de ginjeira (Prunus cerasus L.), localizados no campo de germoplasma da "Direcção Regional de Agricultura da Beira Interior" (Fundão, Portugal). Esses extratos foram analisados para 5 sistemas isoenzimáticos a fim de caracterizar essas variedades e simultaneamente detectar sinonímias e homonímias, freqüentes neste tipo de estudos. As variedades de cerejeira e ginjeira analisadas mostraram baixo polimorfismo isoenzimático, sendo que os sistemas PGM e PGI mostraram maior poder de discriminação. Estes sistemas apresentaram 7 e 5 zimogramas diferentes, respectivamente. IDH mostrou 4 padrões. SKDH e 6-PGD agruparam as variedades em 2 padrões. Os evidentes limites discriminatórios desse tipo de análise serviram somente de complemento para a caracterização agronômica e morfológica.

O objetivo deste trabalho foi avaliar a resistência parcial de genótipos de soja ao fungo Phakopsora pachyrhizi. Calcularam-se o número médio de pústulas, a severidade e a área abaixo da curva de progresso da doença. Foram encontradas diferenças significativas entre os genótipos quanto ao número médio de pústulas e severidade, aos 12 dias após a inoculação. A análise de agrupamento permitiu a discriminação de genótipos parcialmente resistentes. Os genótipos G4, G41 e G42, referentes aos parentais Cristalina e IAC 100, foram detectados como os de maior resistência parcial à ferrugem da soja.The objective of this work was to evaluate the partial resistance of soybean genotypes against Phakopsora pachyrhizi. Resistance characteristics were: average number of pustules, rust severity and the area under the disease progress curve. Significant differences were found among the genotypes for the average number of pustules and rust severity. Multivariate analysis allowed the discrimination of partially resistant genotypes. Three genotypes (G4, G41, and G42), referring to parents Cristalina and IAC 100, presented greater partial resistance to soybean rust.

In order to determine the variability of the bromatological composition of cocoa shells between Amazonia cantons, seven cantons were selected and, from each of them, three farms, according to their production and edaphoclimatic characteristics. For sampling, the "five points" method for plots lower than ten hectares was applied. Statistical relations by analysis of principal components and cluster were analyzed. The total variance indicated that with three principal components which was possible to explain 85.03% of the total variability. The principal component 1 (crude fiber, ether extract and nitrogen-free extract) was identified with the "energetic component", and explained 39.35% of the system variance. The principal component 2 (dry matter and ash) corresponded to the mineral component, and explained 26.2%. The principal component 3 was identified with the crude protein and explained 19.05%. The cut made in the dendrogram to interrupt the forming groups process, ranged 2.52, allowed to join four groups:1) comprising three cantons, characterized by a slight increase of dry matter and ash (90.30 and 9.09%); 2) a canton, with increase of ether extract, nitrogen-free extract and lower crude fiber content (3.61, 57.41, 21.95%); 3) two cantons, with crude protein increase of 8.97% and 4) two cantons with higher crude fiber content (24.93%). It is concluded that the bromatological composition of cocoa shells, from the seven cantons of the Amazonia, can be mainly differentiated by the contents of ether extract, nitrogen-free extract and crude fiber, but remains in the range described in the literature, so they would be good alternatives as substrates in the solid state fermentation processes. [ABSTRACT FROM AUTHOR]

The objectives of this work were to optimize the isozyme electrophoresis technique for Bixa orellana, and use isozyme markers for a preliminary survey on the genetic variability in Brazilian annatto germplasm accessions. Collection consisted of seed samples from sixty open pollinated trees, representing two Northern and four Southern geographic provenances. The extraction, electrophoresis, and interpretation of annatto isozymes are described. Three out of the twenty-one identified isozyme loci were polymorphic in the collection. The percentage of polymorphic loci (P = 21.05) and the expected heterozygosity in annatto (H T = 0.064) were low, compared to other tropical woody species. A UPGMA phenogram, constructed with Nei's genetic distances, clearly separated the germplasm provenant from North and Central Brazil. Variability was significantly higher among the accessions from Maranhão. A sharp genetic differentiation was detected between accessions from Maranhão and Pará States, despite their geographical proximity. The distinctive isozyme polymorphism, observed in the accessions from Maranhão, together with reports on local morphological heterogeneity in annatto fruit shape, color, and pubescence, calls for more detailed genetic and taxonomic investigation.Os objetivos deste trabalho foram: otimizar a técnica de eletroforese de isoenzimas para Bixa orellana, e usar marcadores isoenzimáticos para um estudo preliminar da variabilidade genética, presente em uma coleção de germoplasma de urucum. Foi estudada uma coleção de amostras de sementes oriundas de 60 indivíduos de polinização aberta, que representam duas procedências do Norte e quatro do Sul do Brasil. São descritas a extração, a eletroforese e a interpretação de isoenzimas de urucum. Três, dos vinte e um locos isoenzimáticos identificados, foram polimórficos na coleção examinada. A porcentagem de locos polimórficos (P = 21,05) e a heterozigosidade esperada em urucum (H T = 0,064) foram baixas, em comparação com outras espécies arbóreas tropicais. O dendrograma UPGMA, construído com base nas distâncias genéticas de Nei, diferenciou claramente as procedências de urucum do Norte, daquelas oriundas do Brasil Central. A variabilidade foi significativamente superior na procedência Maranhão. Uma pequena diferenciação genética foi detectada entre os acessos do Maranhão e do Pará, apesar da proximidade geográfica. O polimorfismo isoenzimático diferenciado, observado no germoplasma procedente do Maranhão, somado a relatos de heterogeneidade morfológica local com relação à forma, à cor e à pubescência dos frutos de urucum, sugerem uma investigação genética e taxonômica mais detalhada dessa espécie.

Elephantgrass (Pennisetum purpureum Schum.) is native to regions of tropical Africa and was introduced in Brazil around 1920 through plantings imported from Cuba. It is currently one of the most widespread forage plants throughout the country. At first, there were two cultivars, Napier and Mercker, with well defined characteristics. New genotypes arose and it is believed that the large number of cultivars existing today in germplasm bank is due to duplicates. DNA markers for cultivar characterization are a very valuable tool, especially in situations where morphological and isoenzymatic markers have already been used as in the case of elephantgrass. Thus RAPD markers were used to estimate the genetic divergence among the Napier group elephantgrass cultivars from the elephantgrass Active Germplasm Bank at EMBRAPA Dairy Cattle. The polymerase chain reaction with 37 arbitrary primers from the OPERON Technologies series supplied 94 polymorphic and 73 monomorphic bands. From the matrix of complement of the Nei index, cluster analysis by the Tocher optimization method formed three clusters. Pearson correlation among genetic distance estimates obtained from the DNA markers and the isoenzymatic markers showed the consistency of both the methods in assessing genetic divergence among elephantgrass cultivars. No duplicates were found in the treatments assessed.O capim-elefante (Pennisetum purpureum Schum.) é nativo de regiões da África Tropical e foi introduzido no Brasil por volta de 1920, por meio de mudas provenientes de Cuba, e é, atualmente, uma das forrageiras mais difundidas em todo o país. No início de sua utilização, existiam praticamente dois cultivares com características bem definidas, Napier e Mercker. Com o decorrer do tempo, surgiram novos genótipos e acredita-se que o grande número de cultivares existentes atualmente no Banco de Germoplasma da espécie se deva à ocorrência de duplicatas. O uso de marcadores de DNA na caracterização de cultivares constitui uma ferramenta de grande valor, principalmente em situações em que marcadores morfológicos e isoenzimáticos já foram empregados, caso do capim-elefante. Em vista disso, objetivou-se estimar a divergência genética entre cultivares de capim-elefante do grupo "Napier" provenientes do Banco Ativo de Germoplasma de capim-elefante da EMBRAPA Gado de Leite, por meio de marcadores RAPD. As reações de polimerase em cadeia com 37 iniciadores arbitrários da série OPERON Technologies proporcionaram 94 bandas polimórficas e 73 monomórficas. Por meio da matriz do complemento do índice de Nei, a análise de agrupamento pelo método de otimização de Tocher indicou a formação de três grupos. Correlação de Pearson entre estimativas de distância genética obtidas a partir dos marcadores de DNA e dos marcadores isoenzimáticos indicaram a consistência de ambos os métodos para a avaliação da divergência genética entre cultivares de capim-elefante. Não foram encontradas duplicatas nos tratamentos avaliados.

Glucose is preferentially stored as starch in plants. Thus, the remains of such polysaccharide may represent an invaluable source of archaeological evidence. The genomics, proteomics and metabolomics pathways can be also exploited to ascertain key events in phylogenetic processes. This includes the reconstruction of polyploidization events in plants and the identification of taxonomic positions. These developments are particularly relevant for the study of selection, evolution and domestication events of microorganisms, plants and animals. They include the adaptation to such food resource and the study of paleodiets and their implications for ancient and modern animals, including humans. [ABSTRACT FROM AUTHOR]

Glucose is preferentially stored as starch in plants. Thus, the remains of such polysaccharide may represent an invaluable source of archaeological evidence. The genomics, proteomics and metabolomics pathways can be also exploited to ascertain key events in phylogenetic processes. This includes the reconstruction of polyploidization events in plants and the identification of taxonomic positions. These developments are particularly relevant for the study of selection, evolution and domestication events of microorganisms, plants and animals. They include the adaptation to such food resource and the study of paleodiets and their implications for ancient and modern animals, including humans. [ABSTRACT FROM AUTHOR]

The spiralling whitefly Aleurodicus dispersus Russell (Hemiptera: Aleyrodidae), a highly polyphagous pest, has since about 2000 been an important pest of agricultural and horticultural crops in India. Despite its economic importance, little is known about the level and patterns of genetic variability in populations of the A. dispersus. In this study, we used the simple sequence repeats - polymerase chain reaction (SSR-PCR) technique was used to study the genetic diversity of A dispersus in India. The present study is the first of its kind in India to utilize SSR markers for characterizing A. dispersus populations. A total of 356 different bands were scored using 18 primers for amplification. About 66.0% of alleles were polymorphic in A. dispersus populations. The SSR survey clearly detected moderate levels of polymorphism among the whitefly populations; multiple alleles were identified in many markers. The polymorphism information content (PIC) for SSR primers ranged from 0.0000 to 0.9541. Average genetic distances were estimated in our effort to investigate the level of DNA variation among the 7 geographic populations of A dispersus from southern and northeastern India. The highest average genetic distance (0. 8182) was found between populations from Karnataka and Andhra Pradesh and Meghalaya and Mizoram. An UPGMA dendrogram based on similarity coefficients was constructed for the 7 populations analyzed. The A. dispersus population from Maharashtra was separated from those in the other 6 states viz., Tamil Nadu, Kerala, Andhra Pradesh, Karnataka, Mizoram and Meghalaya [ABSTRACT FROM AUTHOR]

O propósito deste trabalho foi determinar a similaridade genética entre acessos de germoplasma e cultivares comerciais de três espécies de Brachiaria (inter e intraespecífica), por meio de marcadores RAPD. Sementes foram utilizadas como fonte de DNA. 10 “primers” decâmeros foram selecionados de 120 “primers” avaliados, produzindo 107 bandas polimórficas, as quais foram utilizadas para a análise de variância molecular (Amova), o coeficiente de similaridade de Jaccard e índices de fixação gênica. 24,40% da variabilidade genética total estão contidas entre as espécies e 75,60% dentro destas, com índice de fixação gênica (FST) 0,24. No dendrograma, houve a formação de dois ramos, um formado por P. maximum e B. arrecta e o outro subdividido em três: todas amostras de B. ruziziensis; todos os acessos de B. decumbens e três acessos de B. brizantha e o último com dois acessos de B. brizantha mais as B. brizantha comerciais e a B. decumbens cv ‘Basilisk’. Foi possível agrupar os acessos e as cultivares de Brachiaria por meio de RAPD. O índice de variabilidade genética entre espécies foi considerado baixo, sendo inferior a valores determinados em algumas espécies autógamas. B. brizantha apresenta maior variabilidade genética e menor FST indicando maior fluxo gênico intra-específico do que as outras.

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Las técnicas moleculares empleadas para el análisis de ADN cromosomal como el RFLP IS200 han demostrado ser eficientes para resolver relaciones filogenéticas y epidemiológicas entre las cepas de Salmonella spp., aisladas de aves y humanos. El presente estudio tuvo como objetivo determinar si la IS200 estaba presente en las cepas de Salmonella aisladas de aves de corral y de humanos para establecer una posible cadena de transmisión entre ambos. El análisis filogenético de las cepas de Salmonella mostró 13 perfiles de IS200 que exhibieron de 1 a 11 copias de la secuencia de inserción, localizadas en un rango entre 13 y 1.71kb. El trabajo permitió concluir que IS200 es un marcador molecular eficiente, sensible y específico, útil para realizar estudios epidemiológicos ya que discriminó entre cepas de diferentes orígenes y comprobó que existe una relación clonal entre las cepas aviares y humanas. Los resultados obtenidos muestran la necesidad de implementar medidas sanitarias que conlleven a que en la producción se minimicen las condiciones que favorezcan la propagación de Salmonella entre las aves.

A genetic study of seven cultivars of H. psittacorum and Heliconia interspecific hybrids was carried out. The heritability estimate and genetic variation coefficient were highest for stem diameter (SD) (99.32% and 56.90%, respectively) and for CVg/CVe (1.85), indicating a favorable situation for selection. The genetic correlations of SD with days to inflorescence emergence (DIE) (0.64), period from shoot emergence to stem cut (CYCLE) (0.63) and stem weight (SW) (0.96) showed that the time from inflorescence emergence to cut is longer and the stem weight is greater for genotypes with larger stem diameter. Inflorescence length (IL), SD and DIE were the most important traits, accounting for 99.55% of the total variation. For SD and IL, the repeatability values exceeded 0.60 and for SD, SW, DIE and IL the coefficients of determination exceeded 93%. [ABSTRACT FROM AUTHOR]