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

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

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

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

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

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

Behavior of lateral buds of Hancornia speciosa after cryopreservation by encapsulation-vitrification

 Hancornia speciosa is a fruitful species from Cerrado biome with high economic potential. However, the intense and disordered extractivism have caused a reduction of its population in its endemic area. In addition, seed recalcitrance negatively affects the conventional conservation of the species. Aiming to find alternatives that enable the long-term conservation of this species, the study’s objective was to assess the behavior of lateral bud’s regrowth after cryopreservation procedures by encapsulation-vitrification technique. Sodium alginate capsules containing lateral buds were pre-cultured in liquid WPM supplemented with 1.0 M glycerol, and subsequently exposed to different concentrations of sucrose (0.3; 0.75 and 1.0 M) for 24 or 48 hours. The capsules were subjected to dehydration in silica gel or airflow hood for 0, 1, 2 and 3 hours before different incubation times in PVS2 (0, 15, 30, 60 and 120 minutes) at 0°C. A high regeneration percentage of lateral buds was observed after cryopreservation of capsules treated with 0.75 M sucrose plus 1.0 M glycerol (24 hours), associated with dehydration in an airflow hood (1 hour) and immersion in PVS2 (15 minutes). Encapsulation-vitrification allowed the long-term conservation, and provided high plant material survival rates after cryopreservation of Hancornia speciosa sensitive explants.

In vitro germination and cryopreservation of Zinnia elegans seeds

Zinnia elegans Jacquim is a species of big cutting and ornamental potential, but its seeds have low germination percentage. This study aimed to establish a protocol for in vitro germination and water content for the cryopreservation of seeds. The length, width, thickness, and weight of one thousand seeds were determined. MS and WPM culture mediums, as well as the concentrations of gibberellic acid (GA3) were tested regarding in vitro culture. For cryopreservation, the seeds were subjected to drying on silica gel or laminar flow for different times. Then, the seeds were stored in liquid nitrogen (-196° C) for 24 hours. After this period, the seeds were thawed and inoculated into culture medium. The biometric results of seeds showed 8.6 mm average length, 4 mm width, and 0.9 mm thickness. The weight of one thousand seeds was 851 mg, characterizing them as small, lightweight, and easy to disperse. The use of MS medium with no addition of GA3 enhanced germination (67%). The initial moisture content of Z. elegans seeds was 9%. Seeds subjected up to 2 hours of drying in both treatments obtained 23% germination in silica gel and 19% in laminar flow. Z. elegans seeds may be desiccated by 4% moisture content and cryopreserved with no loss of germination potential