SEEDLING EMERGENCE AND GENETIC PARAMETERS OF OPEN-POLLINATED CANDEIA PROGENIES GROWN IN TREE NURSERY

MacLeish is economically appreciated due to its wood and to the extraction of its essential oil, whose active principle is alpha-bisabolol. Despite its economic importance, studies about the genetic breeding of this species remain scarce. The aim of the current study is to determine E. erythropappus seedling emergence rate, genetic parameters, as well as to identify potential open-pollinated progenies of this species and their respective matrices. The experiment was set up in tree nursery, based on a completely randomized design, with 22 progenies in four replicates comprising 14 plants per plot. Seedling emergence rate was evaluated 30 days after seeding, whereas plant height (H) and stem diameter (SD) were measured at 100 days. Statistical analyses were carried out based on the REML/BLUP method. Three progenies have shown seedling emergence rate lower than 50%; this value is considered limiting to seedling production process. Genetic variation was observed among progenies, as well as high and positive genetic correlation between H and SD. Thus, it was possible identifying superior progenies and matrices, as well as the ones presenting low performance in the evaluated traits

Caracterização genética no crescimento inicial de progênies de Eremanthus erythropappus (DC.) MacLeish em Aiuruoca, MG, Brasil

MacLeish in Aiuruoca, Minas Gerais State, Brazil). Eremanthus erythropappus (DC.) MacLeish is a native species, economically appreciated due to its wood and the extraction of essential oil, whose active ingredient is alphabisabolol, but studies on genetic improvement of this species are still scarce. The aim of this study was to evaluate survival, genetic variability and estimate genetic parameters in E. erythropappus progenies in the field at 15, 22 and 30 months of age. The experiment was set up at Fazenda Guapiara, in Aiuruoca, Minas Gerais State, where seedlings of 15 progenies were planted in a randomized block design with five replications and six plants per plot. Plant height evaluations were performed and genetic studies were carried out in the SELEGEN software using the REML/BLUP method. At 30 months, the percentage of seedling survival was evaluated. Significant differences were observed between progenies, and the highest estimates of h²mp (0.48) and Acprog (0.69) were found at 30 months. Therefore, even in the juvenile stage, it was possible to identify genetic variability and analyze its expression over time, which makes it possible to continue studies of genetic improvement of the species.MacLeish em Aiuruoca, MG, Brasil). Eremanthus erythropappus (DC.) MacLeish é uma espécie nativa, apreciada economicamente devido a sua madeira e à extração de óleo essencial, cujo princípio ativo é o alfabisabolol, porém os estudos em melhoramento genético dessa espécie ainda são escassos. Objetivou-se com este trabalho avaliar a sobrevivência e estimar parâmetros genéticos em progênies de E. erythropappus em campo aos 15, 22 e 30 meses de idade. O experimento foi instalado na Fazenda Guapiara, em Aiuruoca, MG, onde foram plantadas mudas de 15 progênies em delineamento de blocos casualizados, com cinco repetições e seis plantas por parcela. Foram realizadas avaliações da altura das plantas e procederam-se aos estudos genéticos no software SELEGEN por meio do método REML/BLUP. Aos 30 meses, foi avaliado o percentual de sobrevivência das mudas. Verificou-se diferenças significativas entre as progênies, e as maiores estimativas de h²mp (0,48) e de Acprog (0,69) foram encontradas aos 30 meses. Portanto, mesmo em estágio juvenil, foi possível identificar variabilidade genética e analisar a sua expressão ao longo do tempo, o que possibilita dar continuidade aos estudos visando o melhoramento genético da espécie

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

Production of pectin lyase by Penicillium griseoroseum in bioreactors in the absence of inducer

Penicillium griseoroseum was grown in bioreactors on mineral medium supplemented with yeast extract and sucrose. The influence of inoculum and carbon source concentrations, aeration and pH on pectin lyase (PL) production, as well as the capacity of P. griseoroseum to produce PL when grown on sugar cane syrup as carbon source were evaluated. Inoculum concentration did not influence PL production. Production was higher in non-aerated than in aerated medium. The best results were obtained using 60 mM sucrose at pH 6.3-7.2. Production using cane syrup 25% (v/v), without yeast extract supplement, was equal to that obtained under the conditions cited above

Production of pectin lyase by Penicillium griseoroseum in bioreactors in the absence of inducer

Penicillium griseoroseum was grown in bioreactors on mineral medium supplemented with yeast extract and sucrose. The influence of inoculum and carbon source concentrations, aeration and pH on pectin lyase (PL) production, as well as the capacity of P. griseoroseum to produce PL when grown on sugar cane syrup as carbon source were evaluated. Inoculum concentration did not influence PL production. Production was higher in non-aerated than in aerated medium. The best results were obtained using 60 mM sucrose at pH 6.3-7.2. Production using cane syrup 25% (v/v), without yeast extract supplement, was equal to that obtained under the conditions cited above.Penicillium griseoroseum foi cultivado em biorreatores em meio mineral suplementado com extrato de levedura e sacarose. As influências das concentrações do inóculo e da fonte de carbono, da aeração e do pH do meio de cultivo sobre a produção de pectina liase (PL), bem como a capacidade de P. griseoroseum em produzir PL quando cultivado em caldo de cana diluído foram avaliadas. A concentração do inóculo não influenciou significativamente a produção de PL. O cultivo do fungo em biorreatores não aerados favoreceu a produção da PL em detrimento aos biorreatores com injeção de ar. Maior produção de PL foi obtida com o cultivo de P. griseoroseum em meio com pH 6,3 – 7,2, adicionado de 60 mM de sacarose. Quando cultivado em caldo de cana diluído, 25% (v/v), sem suplementação com extrato de levedura, a atividade máxima de PL alcançada foi igual as das condições citadas acima

Kinetics of growth and ethanol formation from a mix of glucose/xylose substrate by Kluyveromyces marxianus UFV-3

The fermentation of both glucose and xylose is important to maximize ethanol yield from renewable biomass feedstocks. In this article, we analyze growth, sugar consumption, and ethanol formation by the yeast Kluyveromyces marxianus UFV-3 using various glucose and xylose concentrations and also under conditions of reduced respiratory activity. In almost all the conditions analyzed, glucose repressed xylose assimilation and xylose consumption began after glucose had been exhausted. A remarkable difference was observed when mixtures of 5 g L^−1 glucose/20 g L^−1 xylose and 20 g L^−1 glucose/20 g L^−1 xylose were used. In the former, the xylose consumption began immediately after the glucose depletion. Indeed, there was no striking diauxic phase, as observed in the latter condition, in which there was an interval of 30 h between glucose depletion and the beginning of xylose consumption. Ethanol production was always higher in a mixture of glucose and xylose than in glucose alone. The highest ethanol concentration (8.65 g L^−1) and cell mass concentration (4.42 g L^−1) were achieved after 8 and 74 h, respectively, in a mixture of 20 g L^−1 glucose/20 g L^−1 xylose. When inhibitors of respiration were added to the medium, glucose repression of xylose consumption was alleviated completely and K. marxianus was able to consume xylose and glucose simultaneously