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Morfologia dos tricomas das pétalas de espécies de Pseudobombax Dugand (Malvaceae, Bombacoideae) e seu significado taxon?mico
Carvalho-Sobrinho, Jefferson Guedes de;Santos, Francisco de Assis Ribeiro dos;Queiroz, Luciano Paganucci de;
Acta Botanica Brasilica , 2009, DOI: 10.1590/S0102-33062009000400003
Abstract: trichome morphology of the petals of pseudobombax dugand species was investigated. the eight species selected of pseudobombax were analyzed using optical microscopy and scanning electron microscopy. the study detected the existence of variation, both qualitative and quantitative, in morphology of trichomes in petals of species analyzed. in pseudobombax petals, two kinds of trichomes were found: (a) trichomes 2-4-armed, sessile, long, flexible and with thin walls, situated on the adaxial surface; (b) tufted trichomes, sessile, short, rigid, with thick, lignified walls, on the abaxial surface of the petals. the qualitative and quantitative data were of taxonomic value for the resolution of problems of specific identification in the genus.
EVALUACIóN DEL HáBITAT, LAS POBLACIONES Y EL ESTATUS DE CONSERVACIóN DEL BARRIGóN (CAVANILLESIA CHICAMOCHAE, MALVACEAE - BOMBACOIDEAE)
DíAZ-PéREZ,CARLOS NELSON; PUERTO-HURTADO,MIGUEL ANTONIO; FERNáNDEZ-ALONSO,JOSé LUIS;
Caldasia , 2011,
Abstract: we estimated the degree of threat of the recently described malvaceae-bombacoideae cavanillesia chicamochae fern. alonso, species considered endemic of the chicamocha river canyon and areas along the sogamoso river canyon (santander-colombia). we determined the geographical distribution and habitat of this species based on local historical information and the recognition of the area. the population's state, age structure, and phenology were diagnosed. alongside, the vegetation was characterized by analyzing the disruption and / or threat factors that affect them. a total of 256 individuals were recorded at different altitudes (between 230 - 1100 m) and grouped into five age classes. the best represented were the seedlings with 118 individuals (46.1%), followed by adults 1 with 70 (27.34%). the reproductive period is annual, from late november to early march. the surrounding vegetation is represented by 100 species, 86 genera, and 40 families. the conservation status was determined according to the iucn criteria (2001) as endangered (en) because it has a potential range of 972 km2 and has an actual occupation area of 251 km2. the area has four main agents of disturbance: goat rearing, crop establishment, land instability, and an increasing removal of plants by collectors.
Seed germination and seedling growth of two Pseudobombax species (Malvaceae) with contrasting habitats from Brazilian Cerrado
Clesnan Mendes-Rodrigues,Paulo Eugênio Oliveira,Marli Aparecida Ranal
Revista de Biología Tropical , 2011,
Abstract: Pseudobombax tomentosum and P. longiflorum are common trees in the Cerrado region, but the former species is more common in forest edges while the later is present in open cerrado areas. This work aimed to investigate differences in seed germination and seedling growth in these species, from seed collected from Cerrado areas in Central Brazil. For this, a seed germination experiment was designed and included four replicates with 25 seeds per species; seeds were randomly distributed in the germination chamber. To evaluate initial seedling growth, seedlings height was measured up to 67 days after seedling emergence; besides, some of these seedlings were grown for biomass evaluation during nine months. Results showed that seeds of the two species had the same germinability (near 100%) and mean germination time (ca. 12 days). However, P. longiflorum showed a more spread seed germination through time, with higher values of coefficient of variation in germination time and uncertainty index; and lower values of synchronization than P. tomentosum. The two species showed basically the same growth pattern, but lower values for height of apical meristem, diameter of underground structures (mostly roots), dry mass of shoots, underground structure and total mass of seedlings in P. tomentosum were obtained, compared to P. longiflorum. Both species allocated more dry mass to underground structures in detriment of shoot. This probably allows resprouting behavior which prevents hydric stress and detrimental fire action typical of the open Cerrado areas. Rev. Biol. Trop. 59 (4): 1915-1925. Epub 2011 December 01. Pseudobombax tomentosum y P. longiflorum son árboles comunes en la región del Cerrado, pero la primera especie es más común en los bordes del bosque mientras que el segundo está presente en áreas abiertas del cerrado. Este trabajo tuvo como objetivo investigar las diferencias en la germinación de las semillas y el crecimiento de ambas especies. Los individuos fueron recolectados en áreas del Cerrado, la región de savanas neotropicales en el centro de Brasil. Fueron utilizados para cada especie cuatro repeticiones con 25 semillas cada una para el experimento de germinación, distribuidas al azar en la cámara de germinación a 25oC. Las plántulas fueron evaluadas en cuanto al crecimiento inicial hasta 67 días después de la emergencia de la plántula. Algunas plantas se mantuvieron para la evaluación de la biomasa durante nueve meses, y luego se mideron para evaluar diferencias en el crecimiento y distribución de masas entre especies. Ambas presentaron la misma capacida
Seed germination and seedling growth of two Pseudobombax species (Malvaceae) with contrasting habitats from Brazilian Cerrado
Mendes-Rodrigues,Clesnan; Oliveira,Paulo Eugênio; Ranal,Marli Aparecida;
Revista de Biología Tropical , 2011,
Abstract: pseudobombax tomentosum and p. longiflorum are common trees in the cerrado region, but the former species is more common in forest edges while the later is present in open cerrado areas. this work aimed to investigate differences in seed germination and seedling growth in these species, from seed collected from cerrado areas in central brazil. for this, a seed germination experiment was designed and included four replicates with 25 seeds per species; seeds were randomly distributed in the germination chamber. to evaluate initial seedling growth, seedlings height was measured up to 67 days after seedling emergence; besides, some of these seedlings were grown for biomass evaluation during nine months. results showed that seeds of the two species had the same germinability (near 100%) and mean germination time (ca. 12 days). however, p. longiflorum showed a more spread seed germination through time, with higher values of coefficient of variation in germination time and uncertainty index; and lower values of synchronization than p. tomentosum. the two species showed basically the same growth pattern, but lower values for height of apical meristem, diameter of underground structures (mostly roots), dry mass of shoots, underground structure and total mass of seedlings in p. tomentosum were obtained, compared to p. longiflorum. both species allocated more dry mass to underground structures in detriment of shoot. this probably allows resprouting behavior which prevents hydric stress and detrimental fire action typical of the open cerrado areas. rev. biol. trop. 59 (4): 1915-1925. epub 2011 december 01.
Armando Dugand: El científico barranquillero del siglo XX  [cached]
Jairo Solano Alonso
Memorias: Revista Digital de Historia y Arqueología desde el Caribe , 2006,
Abstract: El presente estudio es un avance de un trabajo mayor, sobre el botánico Armando Dugand Gnecco, considerado el más importante científico oriundo de la ciudad de Barranquilla que durante el siglo XX, tuvo audiencia y visibilidad nacional e internacional de las comunidades científicas de las Ciencias biológicas que practicaba. Se trata de un trabajo de biobibliografía científica muy afín a la tradición de la Historia Social de la ciencia.
NUEVAS ESPECIES DE MALVACEAE New species of Malvaceae
Antonio Krapovickas
Bonplandia , 2010,
Abstract: Se describen seis especies nuevas de Malvaceae: Abutilon heterochros, Gaya ibitipocana, Sida itaparicana, Sida Arboae y Sida Meloana de Brasil e Hibiscus manuripiensis de Bolivia Six new species of Malvaceae are described: Abutilon heterochros, Gaya ibitipocana, Sida itaparicana, Sida Arboae and Sida Meloana from Brasil and Hibiscus manuripiensis from Bolivia
Nuevas especies de Malvaceae
Antonio Krapovickas
Bonplandia , 2008,
Abstract: Se describen seis especies nuevas de Malvaceae: Abutilon heterochros, Gaya ibitipocana, Sida itaparicana, Sida Arboae y Sida Meloana de Brasil e Hibiscus manuripiensis de Bolivia
Are the Alien Species of Melastomataceae and Bombacoideae a Potential Risk for Brazilian Cerrado?
Clesnan Mendes-Rodrigues, Paulo Eugênio Oliveira, Rafaela Cabral Marinho, Rosana Romero, Marli A. Ranal
Open Access Library Journal (OALib Journal) , 2019, DOI: 10.4236/oalib.1105156
Abstract:
The cultivation of species in urban areas for landscaping or consumption has increased in cities surrounded by Cerrado, putting in risk the local flora. Thus, the objective of this paper was to describe seed germination and seedling emergence of five urban cultivated species of Melastomataceae and Bombacoideae and compare them with Cerrado native species to evaluate if they offer any risk to local vegetation. The seeds were collected in the urban area of Uberlandia, within the Brazilian Cerrado. We calculated germination and emergence measurements and compared them to literature data. Seeds of Bombax ceiba and Pachira aquatica had a germination and emergence pattern similar to other Bombacoideae. Tibouchina pulchra and Tibouchina granulosa also had a similar pattern to other Melastomataceae, with low germinability. In contrast, seed germination of Heterotis rotundifolia, an invasive African species, was similar to Clidemia hirta, also known as invasive, including the higher spreading of germination through time, a common character of invasive plants. Seed germination of H. rotundifolia was more similar to Cerrado species with dormant seeds, showing high germinability and germination spread through time. These features added to its fast-growing due to its decumbent herbaceous habit that forms dense mats could offer risks to local species. Thus, it is being recommended that its populations be monitored.
On the role of assumptions in cladistic biogeographical analyses
Santos, Charles Morphy Dias dos;
Papéis Avulsos de Zoologia (S?o Paulo) , 2011, DOI: 10.1590/S0031-10492011001900001
Abstract: the biogeographical assumptions 0, 1, and 2 (respectively a0, a1 and a2) are theoretical terms used to interpret and resolve incongruence in order to find general areagrams. the aim of this paper is to suggest the use of a2 instead of a0 and a1 in solving uncertainties during cladistic biogeographical analyses. in a theoretical example, using component analysis and primary brooks parsimony analysis (primary bpa), a2 allows for the reconstruction of the true sequence of disjunction events within a hypothetical scenario, while a0 adds spurious area relationships. a0, a1 and a2 are interpretations of the relationships between areas, not between taxa. since area relationships are not equivalent to cladistic relationships, it is inappropriate to use the distributional information of taxa to resolve ambiguous patterns in areagrams, as a0 does. although ambiguity in areagrams is virtually impossible to explain, a2 is better and more neutral than any other biogeographical assumption.
Observa??o da visita de morcegos (Chiroptera) às flores de Pseudobombax grandiflorum (Cav.) A. Robyns
Silva, Shirley S. Pereira da;Peracchi, Adriano Lúcio;
Revista Brasileira de Zoologia , 1995, DOI: 10.1590/S0101-81751995000400015
Abstract: the visit of two species of bats to the flowers of pseudobombax grandiflorum (cav.) a. robyns was observed in the federal rural university of rio de janeiro during the period of may and july of 1989. the flowers of this vegetal species present attributions in accordance to the syndrome of chiropterophily and receive the visit of glossophaga soricina (pallas. 1766) and phyllostomus hastatus (pallas. 1767). glossophaga soricina has morfological caracteristes for nectarivory, phyllostomus hastatus is omnivorous and starts its visils soon after the anthesis. that bats present landing behaviour during the visit.
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