18 research outputs found

    Desenvolvimento de mudas de guanandi (Calophyllum brasiliens Cambess.) sob diferentes condições de sombreamento

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    Guanandi is a tree species greatly valued for its wood and widely used in mixed reforestation programs in degraded riparian forests. We aimed to evaluate the relationship between the initial development of the species saplings and shading levels, by analyzing variations in the concentration of chlorophylls (a/b), carotenoids, and foliar nitrogen, as well as biomass accumulation. Treatments with intermediary shading (30% and 50%) resulted in increased height and increased stem secondary growth. The lowest foliar nitrogen content was found in saplings grown under 70% shading. Saplings grown under 50% shading showed lower levels of chlorophyll a than of chlorophyll b, and consequently a lower chlorophyll a/b ratio than plants subjected to the other treatments. Overall, the best vegetative performance was observed in saplings grown under 30% and 50% shading. The full-sun growth condition is not recommended for the initial development of guanandi saplings.Guanandi é uma espécie arbórea muito utilizada na obtenção de madeira e em programas de reflorestamentos mistos de matas ciliares degradadas. Objetivou-se caracterizar o desenvolvimento de mudas sob diferentes níveis de sombreamento, pleno sol, 30%, 50% e 70%, avaliando-se características físicas e químicas das plantas. Tratamentos com sombreamento intermediário (30% e 50%) foram os que exibiram as plantas com maior altura e crescimento secundário de caule. Menor teor de nitrogênio foliar foi encontrado em mudas a 70% de sombreamento. Já as mudas crescidas em 50% de sombreamento mostraram menores valores de clorofila a do que de clorofila b, com menor relação clorofila a/b. O melhor desempenho vegetativo das mudas foi obtido sob 30% e 50% de sombreamento, sendo a condição de pleno sol não recomendada para a formação de mudas da espécie

    Micropropagação de candeia, uma espécie nativa do cerrado brasileiro

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    Candeia (Eremanthus elytropappus) is a native species from Brazilian Cerrado and presenting economic potential for the timber and pharmaceutical industry. However, the ex vitro germination rate of the seeds is considered low. In this context, the objective was to establish a protocol for in vitro germination and multiplication, aiming at the rapid multiplication of the species. For the in vitro germination medium were tested WPM; ½ WPM; ¼ WPM; MS; MS ½ and ¼ MS. In addition, Were Also tested GA3 (0.0; 0.2; 0.4; 0.6; 0.8 mg L-1) and pH levels (4.8, 5.8 and 6.8) in ¼ WPM culture medium. For in vitro multiplication, stem segments were inoculated in ¼ WPM supplemented with BAP (0.0, 1.0, 2.0, 3.0, 4.0 and 5.0 mg L-1). Shoots obtained in vitro were individually and inoculated in WPM ¼ culture, supplemented with IBA (0.0, 1.0, 2.0, 3.0, 4.0 mg L-1) and 1.5 g L-1 of activated carbon for the in vitro rooting. The shoots were transferred to plastic tubes containing Plantmax® for acclimatization. The more efficient culture medium for in vitro germination is ¼ WPM supplemented with 0.56 mg L-1 GA3 and pH 4.8. For multiplication must be used ¼ WPM medium supplemented with 2.8 mg L-1 BAP and 3.1 mg L-1 IBA. The plants showed 70% of ex vitro acclimatization.Candeia (Eremanthus erythropappus) é uma espécie nativa do Cerrado que apresenta potencial econômico para a indústria madeireira e farmacêutica. Entretanto, a taxa de germinação ex vitro das sementes é considerada baixa. Neste contexto, objetivou-se estabelecer um protocolo para germinação e multiplicação in vitro, visando a rápida multiplicação da espécie. Para a germinação in vitro foram testados os meios de cultura WPM; ½ WPM; ¼ WPM; MS; ½ MS e ¼ MS. Além disso, também foram testadas concentrações de GA3 (0,0; 0,2; 0,4; 0,6; 0,8 mg L-1) e níveis de pH (4,8, 5,8 e 6,8) no meio de cultura ¼ WPM. Para a multiplicação in vitro, segmentos caulinares foram inoculados em meio de cultura ¼ WPM, suplementado com BAP (0,0; 1,0; 2,0; 3,0; 4,0 e 5,0 mg L-1). Brotações obtidas in vitro foram individualizadas e inoculadas em meio de cultura ¼ WPM, suplementado com AIB (0,0; 1,0; 2,0; 3,0; 4,0 mg L-1) e 1,5 g L-1 de carvão ativado para o enraizamento in vitro. As brotações foram transferidas para tubetes contendo Plantmax® para posterior aclimatização. Conclui-se que o meio de cultura mais eficiente para a germinação in vitro de candeia é o ¼ WPM suplementado com 0,56 mg L-1 de GA3, e nível de pH 4,8. Para a multiplicação deve ser utilizado o meio ¼ WPM suplementado com 2,8 mg L-1 de BAP e 3,1 mg L-1 de AIB. As plantas apresentaram 70% de aclimatização ex vitro

    Germinação in vitro e criopreservação de sementes de paineira-rosa

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    The paineira-rosa (Chorisia speciosa St. Hil) is an arboreal species of great importance in restoring degraded ecosystems and riparian forests, however, the availability of seeds of this species is low. The objective was to establish in vitro germination protocols and cryopreservation of paineira-rosa seeds. For the in vitro germination, MS culture medium and WPM was tested three concentrations of sucrose (0, 15, 30 g L-1) and three pH levels (4.8, 5.8 and 6.8). For cryopreservation, the seeds were dried on silica gel or laminar flow for different times (0, 1, 2, 3 and 4 h) and then were stored in liquid nitrogen (-196 °C) for 24 h, defrosted in a water bath (38 °C) for four minutes and they were inserted into test tubes containing WPM medium cultivation. The paineira-rosa seeds showed germination when inoculated in WPM (84%). The concentration of 15 g L-1 sucrose and the pH adjusted to 5.8, favored seed germination with 79% and 82%, respectively. The initial water content rose from paineira-rosa seeds was 14%. After 4 h of dehydration on silica gel or laminar flow, the water content was 7.8% and 6.8%, respectively. There was no significant loss of viability of seeds subjected to 4 h of drying in laminar flow (63.33%). The results obtained in this study indicate that the in vitro germination and kapok pink seed cryopreservation can be successfully obtained.A paineira-rosa (Chorisia speciosa St. Hil) é uma espécie arbórea de grande importância na recuperação de ecossistemas degradados e matas ciliares, porém, o armazenamento convencional das sementes aumenta a incidência de fungos, causando deterioração e lesões nas plântulas. Objetivou-se estabelecer protocolos de germinação in vitro e de criopreservação para o armazenamento em longo prazo das sementes de paineira-rosa. Para a germinação in vitro, testou-se os meios de cultura MS e WPM, três níveis de pH (4,8; 5,8 e 6,8) e três concentrações de sacarose (0; 15; 30 g L-1). Para a criopreservação, as sementes foram submetidas à secagem em sílica gel e fluxo laminar por diferentes tempos (0, 1, 2, 3 e 4 h) e em seguida, foram armazenadas em nitrogênio líquido (-196 ºC) por 24 h, descongeladas em banho-maria (38 ºC) por quatro min e inseridas em tubos de ensaio contendo meio de cultura WPM. As sementes de paineira-rosa apresentaram germinação superior em meio de cultura WPM (84%). O pH corrigido para 5,8 e a concentração de 15 g L-1 de sacarose favoreceram a germinação das sementes, com 82% e 79%, respectivamente. O teor de água inicial das sementes de paineira-rosa foi de 14%. Após 4 h de desidratação em sílica gel e fluxo laminar, o teor de água foi de 7,8% e 6,8%, respectivamente. Não houve perda significativa da viabilidade das sementes submetidas à 4 h de secagem em fluxo laminar, com germinação de 63,33%. Os resultados alcançados nesse estudo indicam que a germinação in vitro e a criopreservação de sementes de paineira-rosa podem ser obtidos com sucesso

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Catálogo Taxonômico da Fauna do Brasil: setting the baseline knowledge on the animal diversity in Brazil

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    The limited temporal completeness and taxonomic accuracy of species lists, made available in a traditional manner in scientific publications, has always represented a problem. These lists are invariably limited to a few taxonomic groups and do not represent up-to-date knowledge of all species and classifications. In this context, the Brazilian megadiverse fauna is no exception, and the Catálogo Taxonômico da Fauna do Brasil (CTFB) (http://fauna.jbrj.gov.br/), made public in 2015, represents a database on biodiversity anchored on a list of valid and expertly recognized scientific names of animals in Brazil. The CTFB is updated in near real time by a team of more than 800 specialists. By January 1, 2024, the CTFB compiled 133,691 nominal species, with 125,138 that were considered valid. Most of the valid species were arthropods (82.3%, with more than 102,000 species) and chordates (7.69%, with over 11,000 species). These taxa were followed by a cluster composed of Mollusca (3,567 species), Platyhelminthes (2,292 species), Annelida (1,833 species), and Nematoda (1,447 species). All remaining groups had less than 1,000 species reported in Brazil, with Cnidaria (831 species), Porifera (628 species), Rotifera (606 species), and Bryozoa (520 species) representing those with more than 500 species. Analysis of the CTFB database can facilitate and direct efforts towards the discovery of new species in Brazil, but it is also fundamental in providing the best available list of valid nominal species to users, including those in science, health, conservation efforts, and any initiative involving animals. The importance of the CTFB is evidenced by the elevated number of citations in the scientific literature in diverse areas of biology, law, anthropology, education, forensic science, and veterinary science, among others
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