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1.
Acta toxicol. argent ; 28(1): 19-22, Apr. 2020. graf
Article in Spanish | LILACS | ID: biblio-1248665

ABSTRACT

Resumen La micrografía analítica es una herramienta útil para la identificación de restos vegetales en muestras de material trozado o molido que no podrían ser identificadas de forma morfológica. El objetivo de este estudio es conocer los caracteres mi- crográficos de las semillas de Cebil (Anadenanthera colubrina var. cebil (Griseb.) Altschul, Leguminosae) y Chamico (Datura ferox L., Solanaceae), con el fin de proporcionar parámetros empleables para su identificación en un contexto forense y toxicológico. Los caracteres micrográficos relacionados con el tegumento exterior y las esclereidas fueron los más indicados para diferenciar entre ambas especies.


Abstract Analytical micrography is a useful tool for the identification of plant parts that can't be identified for its morphological characters. The aim of this work is to obtain micrographic characters of Cebil (Anadenanthera colubrina var. cebil (Griseb.) Altschul, Leguminosae) and Chamico (Datura ferox L., Solanaceae) seeds for its identification in a toxicological and forensic context. The most suitable micrographic features were the ones related with exterior testa and the stone cells.


Subject(s)
Seeds/cytology , Solanaceae/cytology , Hallucinogens , Fabaceae/cytology , Argentina , Plant Poisoning/diagnosis , Photomicrography/methods
2.
Rev. biol. trop ; 57(1/2): 303-319, March-June 2009. ilus, tab
Article in English | LILACS | ID: lil-637720

ABSTRACT

We studied the wood anatomy of 29 species belonging to 10 genera of the tribe Detarieae, subfamily Caesalpinioideae and compare them with tribe Caesalpinieae. Detarieae is the largest of four tribes of Caesalpinioideae, with 84 genera, only eleven occur in Venezuela with species of timber importance. The specimens were collected in Venezuela and include wood samples from the collection of the Laboratorio de Anatomía de Maderas de la Facultad de Ciencias Forestales y Ambientales de la Universidad de Los Andes, Venezuela, and of the Forest Products Laboratory of the USDA Forest Service in Madison, Wisconsin, USA. The terminology and methodology used followed the IAWA List of Microscopic Features for Hardwood identification of the IAWA Committee, 1989. Measurements from each specimen were averaged (vessel diameters, vessel element lengths, intervessels pit size, fibre lengths and ray height). The species of Detarieae can be separated using a combination of diagnostic features. Wood characters that provide the most important diagnosis and may be used in systematics of Detarieae include: intercellular axial canals, rays heterocellular, rays exclusively or predominantly uniseriate, prismatic crystals common in ray cells, irregular storied structure and fibre wall thickness. For comparative anatomy between Detarieae and Caesalpinieae: intercellular axial canals, heterocellular rays, rays exclusively or predominantly uniseriate, prismatic crystals common in ray cells (in Detarieae) and regular storied structure, fibres septate, fibre wall thick or very thick, rays homocellular, multiseriate rays and silica bodies (in Caesalpinieae). Axial parenchyma is typically a good diagnostic feature for Leguminosae, but not for Detarieae and Caesalpinieae comparisons. Rev. Biol. Trop. 57 (1-2): 303-319. Epub 2009 June 30.


Se estudió la anatomía de la madera de 29 especies de 10 géneros de la tribu Detarieae, subfamilia Caesalpinioideae, enfocado hacia la identificación de la estructura de la madera y su comparación con la tribu Caesalpinieae. Los especímenes fueron recolectados en Venezuela y pertenecen a la colecciones de maderas del Laboratorio de Anatomía de Maderas de la Facultad de Ciencias Forestales y Ambientales de la Universidad de Los Andes, Mérida, Venezuela y del USDA Forest Service, Forest Products Laboratory, Madison, Wisconsin, USA. Las características anatómicas evaluadas siguen lo propuesto por IAWA List of Microscopic Features for Hardwood identification (IAWA Committee 1989). Las especies de la tribu Detarieae pueden ser identificadas usando un número de características de diagnóstico combinadas: canales intercelulares longitudinales, radios heterocelulares exclusiva o predominantemente uniseriados, patrones del parénquima axial, cristales prismáticos en las células radiales, estructura estratificada y grosor de las paredes de las fibras. Estos caracteres también proporcionan una valiosa información para estudios sistemáticos y filogenéticos. Se presenta la descripción anatómica a nivel de género, una tabla sinóptica con los caracteres de diagnóstico principales y fotomicrografías de las características más importantes.


Subject(s)
Fabaceae/anatomy & histology , Wood/anatomy & histology , Fabaceae/classification , Fabaceae/cytology , Photomicrography , Venezuela , Wood/cytology
3.
Rev. biol. trop ; 56(3): 1075-1086, sep. 2008. ilus, tab
Article in Spanish | LILACS | ID: lil-637848

ABSTRACT

Seed morphology and anatomy of the seed coat in five species of Calliandra (Leguminosae-Mimosoideae) from Venezuela. Calliandra is an exclusively Neotropoical genus with 135 described species. There are 30 species in Venezuela. We studied seed morphology and the seed coat anatomy of five species: Calliandra riparia Pittier, Calliandra glomerulata Karsten var. glomerulata, Calliandra magdalenae (DC.) Benth. var. magdalenae, Calliandra surinamensis Benth. and Calliandra falcata Benth., to establish simililarities and differences amongst taxa for taxonomic characterization. Of the evaluated characters, 10 quantitative characters and 3 qualitative characters were selected as the most informative for the separation of species. Seed morphological characters of taxonomic value are form and size. Thickness of the light line, number of layers and space between the osteosclereids constitute distinctive characters. Rev. Biol. Trop. 56 (3): 1075-1086. Epub 2008 September 30.


Se estudió la morfología de las semillas y la anatomía de la cubierta seminal en cinco especies venezolanas del género Calliandra, con la finalidad de establecer similitudes y diferencias entre estos taxa, para su utilización como criterio taxonómico. Se analizaron caracteres morfológicos de valor taxonómico; entre ellos la forma y el tamaño de la semilla, así como anatómicos tales como espesor de las diferentes regiones, la ubicación de la línea lúcida y el tamaño relativo de los espacios intercelulares en la hipodermis. Con los resultados se realizaron análisis de agrupamiento por medio de la función de análisis discriminante. Diez caracteres cuantitativos, y tres caracteres cualitativos, resultaron informativos para la separación de especies.


Subject(s)
Fabaceae/anatomy & histology , Seeds/anatomy & histology , Fabaceae/classification , Fabaceae/cytology , Seeds/classification , Seeds/cytology , Venezuela
4.
Braz. j. biol ; 65(3): 483-494, Aug. 2005. ilus
Article in English | LILACS | ID: lil-418151

ABSTRACT

O presente trabalho foi desenvolvido com o objetivo de descrever a estrutura da semente de Pterodon emarginatus, nas várias fases do desenvolvimento, utilizando técnicas usuais. Verificou-se que os óvulos são campilótropos, crassinucelados e bitegumentados. Durante o desenvolvimento tegumentar ocorrem os seguintes processos: divisões anticlinais e acúmulo de compostos fenólicos na exotesta, cujas células tornam-se paliçádicas; divisões predominantemente periclinais e alongamento na mesotesta, onde se diferencia o feixe rafeal; diferenciação, adjacente à paliçada, da camada de células em ampulheta; coalescimento do tégmen junto à testa, culminando no concrescimento dos dois tegumentos, que se mantêm individualizados apenas na região micropilar; intensa impregnação de compostos pécticos nas paredes espessadas da mesotesta, com lignificação restrita ao xilema. Na região hilar, desenvolve-se a estrutura característica das sementes de Faboideae, com dupla camada paliçádica, parênquima subhilar e barra de traqueídes. O nucelo é consumido durante a formação da semente, observando-se, na estrutura jovem, células de paredes pécticas espessadas. O endosperma é nuclear e, após a celularização, exibe perifericamente células de conteúdo denso; é encontrado na semente madura, embora se apresente reduzido, acumulando substâncias lipídicas. O embrião é axial, com cotilédones crassos, que acumulam reservas de natureza lipídica e protéica, sendo raros os grãos de amido. Embora a estrutura observada seja típica das Fabaceae, não há reabsorção do tegumento interno, mas concrescimento ao externo.


Subject(s)
Fabaceae/anatomy & histology , Seeds/anatomy & histology , Fabaceae/cytology , Fabaceae/growth & development , Seeds/cytology , Seeds/growth & development
5.
Arch. latinoam. nutr ; 48(1): 41-6, mar. 1998. tab
Article in English | LILACS | ID: lil-217536

ABSTRACT

Four samples each of black beans representing two types of vegetative growth were collected from farmers' fields in four locationes in Guatemala. Soon after collection, samples were stored at 4 and 38 degrees Celsius at ambient relative humidity and subsamples were withdrawn at 0,45, 90 and 135 days of strage for determination of water absorption, cooking time and analysis of neutral-and acid detergent fiber, cellulose, hemicellulose and lignin. The fiber fraction analysis were done on samples of 0,45 and 90 days of storage. Water absorption for all 4 samples of the bush type was similar at both storage T, however the samples stored at 38 degrees Celsius and at 135 days absorbed more water than when stored at 4 degrees Celsius. The 4 vine types of beans showed different water absorption rates, with two showing patterns similar to those beans of the bush type and two which did absorbed water at a very slow rate. For both types of beans stored at 4 degrees Celsius, cooking time decreased from 0 to 135 days of storage. On the other hand for all bean samples of the two types cooking time increased when stored at 38 degrees Celsius. Analysis of variance showed highly significant effects due to plant type, days of storage, temperature and locality, and for some interactions. Analysis of variance of the fiber fractions showed high significant differences for days of storage for NDF, ADF, cellulose, hemicellulose, and lignin. Plant type gave significant differences for cellulose and hemicellulose. Highly significant differences for hemicellulose were found for the interactions of type x days, type x temperature, locality x type, and type x days x temperature. The rate of synthesis of the 5 fractions were calculated by simple regression analysis. For the bush type of beans some synthesis occurred at 4 degrees Celsius, but it was enhanced when stored at 38 degrees Celsius. For vine type of beans at 4 degrees Celsius relative high rates of synthesis were observed, which were higher at 38 degrees Celsius for NDF, hemicellulose and lignin. Cooking time and fiber fraction contents were subjected to regression analysis. The correlations at 38 degrees Celsius were higher than at 4 degrees Celsius for all fractions for both types of beans, but statistical significance was obtained only for NDF, ADF and cellulose for vince type of beans. These data show therefore that synthesis of cell wall structure fractions, and not only lignin formation, are responsible...


Subject(s)
Fabaceae , Food Handling/methods , Analysis of Variance , Cell Wall/metabolism , Fabaceae/cytology , Fabaceae/growth & development , Guatemala , Time Factors
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