EMERGÊNCIA E ESTABELECIMENTO DE PLÂNTULAS DE Guazuma ulmifolia LAM. EM FUNÇÃO DE DIFERENTES TRATAMENTOS PRÉ-GERMINATIVOS

This study tested the influence of mechanical and thermal scarification methods on emergence and establishment of Guazuma ulmifolia seedlings. Seeds were subjected to pre-germination treatments of (1) mechanical scarification (sandpaper), and (2) thermal scarification (hot water), in addition to the control treatment (3) from which the seeds were left intact. The thermal scarification treatment differed from the other treatments featuring the largest number of seedling emergence (70%). The seeds treated with sandpaper achieved the lowest emergence percentage not differing from the control treatment. For the germination speed index no significant difference between treatments has been verified and the emergence peak was between the 13rd and 15th days of incubation in all treatments. In the establishment, the seedlings growth (height, diameter and number of leaves and nodes) presented differences between the treatments. It was observed further development of seedlings after their seeds go through thermal scarification. Therefore, scarification with hot water is the most appropriate method for breaking the dormancy of seeds of Guazuma ulmifolia, providing more vigorous seedlings.Este trabalho testou a influência de métodos de escarificação térmica e mecânica na emergência e estabelecimento de plântulas de Guazuma ulmifolia.As sementes foram submetidas aos tratamentos pré-germinativos de (1) escarificação mecânica (lixa), e (2) escarificação térmica (água quente), além do tratamento-controle (3) no qual as sementes foram deixadas intactas. O tratamento feito com escarificação térmica diferiu dos demais tratamentos, apresentando o maior número de plântulas emergidas. As sementes tratadas com lixa obtiveram a menor porcentagem de emergência, não diferindo do tratamento-controle. Para o índice de velocidade de germinação não foi verificada diferença significativa entre os tratamentos e o pico de emergência de plântulas foi entre o 13º e 15º dia de incubação em todos os tratamentos. Quanto ao estabelecimento, o crescimento (altura, diâmetro e número de folhas e de nós) das plântulas diferiu entre os tratamentos pré-germinativos. Observou-se maior crescimento das plântulas após suas sementes passarem por escarificação térmica. Assim, a escarificação com água quente é o método mais adequado para quebra da dormência das sementes de Guazuma ulmifolia, proporcionando plântulas mais vigorosas

SEEDLING EMERGENCE AND ESTABLISHMENT OF Guazuma ulmifolia LAM. SUBMITTED TO DIFFERENT PRE-GERMINATION TREATMENTS

Este trabalho testou a influ\ueancia de m\ue9todos de escarifica\ue7\ue3o t\ue9rmica e mec\ue2nica na emerg\ueancia e estabelecimento de pl\ue2ntulas de Guazuma ulmifolia . As sementes foram submetidas aos tratamentos pr\ue9-germinativos de (1) escarifica\ue7\ue3o mec\ue2nica (lixa), e (2) escarifica\ue7\ue3o t\ue9rmica (\ue1gua quente), al\ue9m do tratamento-controle (3) no qual as sementes foram deixadas intactas. O tratamento feito com escarifica\ue7\ue3o t\ue9rmica diferiu dos demais tratamentos, apresentando o maior n\ufamero de pl\ue2ntulas emergidas. As sementes tratadas com lixa obtiveram a menor porcentagem de emerg\ueancia, n\ue3o diferindo do tratamento-controle. Para o \uedndice de velocidade de germina\ue7\ue3o n\ue3o foi verificada diferen\ue7a significativa entre os tratamentos e o pico de emerg\ueancia de pl\ue2ntulas foi entre o 13\uba e 15\uba dia de incuba\ue7\ue3o em todos os tratamentos. Quanto ao estabelecimento, o crescimento (altura, di\ue2metro e n\ufamero de folhas e de n\uf3s) das pl\ue2ntulas diferiu entre os tratamentos pr\ue9-germinativos. Observou-se maior crescimento das pl\ue2ntulas ap\uf3s suas sementes passarem por escarifica\ue7\ue3o t\ue9rmica. Assim, a escarifica\ue7\ue3o com \ue1gua quente \ue9 o m\ue9todo mais adequado para quebra da dorm\ueancia das sementes de Guazuma ulmifolia, proporcionando pl\ue2ntulas mais vigorosasThis study tested the influence of mechanical and thermal scarification methods on emergence and establishment of Guazuma ulmifolia seedlings. Seeds were subjected to pre-germination treatments of (1) mechanical scarification (sandpaper), and (2) thermal scarification (hot water), in addition to the control treatment (3) from which the seeds were left intact. The thermal scarification treatment differed from the other treatments featuring the largest number of seedling emergence (70%). The seeds treated with sandpaper achieved the lowest emergence percentage not differing from the control treatment. For the germination speed index no significant difference between treatments has been verified and the emergence peak was between the 13rd and 15th days of incubation in all treatments. In the establishment, the seedlings growth (height, diameter and number of leaves and nodes) presented differences between the treatments. It was observed further development of seedlings after their seeds go through thermal scarification. Therefore, scarification with hot water is the most appropriate method for breaking the dormancy of seeds of Guazuma ulmifolia, providing more vigorous seedlings

Enzimas fúngicas em dietas com alimentos alternativos para frangos de crescimento lento

The feeding represents most of the total cost of production and to reduce costs and increase the profit of the producer have been researched alternative food, as the pie of babassu palm, the pie of palm and the cassava bagasse, which show potential for use in feeding the chickens for slow growth, however, with limited use, due to the different grades of fiber. Non-starch polysaccharides make it difficult for digestible enzymes to reach the food, reducing the digestibility of nutrients. To minimize this effect, exogenous enzymes have been supplemented in poultry diets. Various sources can originate these additives, most of which are acquired through fermentation processes. The temperature, pH, substrate concentration and composition of the ingredients are factors that influence the enzymatic action and consequently the availability of the nutrients. Studies show that the use of fungal enzymes can increase the nutritional value of the food and improves the digestibility of nutrients, reflecting the productive efficiency, representing savings in production costs and benefits to the environment, however, it is necessary to evaluate the use in diets with alternative foods of Regional expression. Keywords: Zootechnical additives; Enzymatic activity; Non-starch polysaccharides.Su objetivo era abordar en esta revisión sobre las enzimas fúngicas y sus efectos sobre las dietas con alimentos alternativos para los pollos de crecimiento lento. La alimentación representa la mayor parte del coste total de la producción y reducir los costes y aumentar lucre del productor se han investigado alimento alternativo, tal como la torta de babasú, la torta de palmiste y bagazo de yuca, que demuestra el potencial para su uso em la alimentación pollos cateto, sin embargo, conun uso limitado debido a los diferentes contenidos de fibra. Polisacáridos no amiláceos dificultan el acceso de las enzimas digestible acerca de los alimentos, lo que reduce la digestibilidad de los nutrientes. Para minimizar este efecto, se han complementado enzimas exógenas em las dietas de las aves. Varias fuentes pueden originate a estos aditivos, la mayoría adquirida através de los procesos de fermentación. La temperatura, pH, concentración de sustrato y la composición de los ingredientes son factores que afectan a la actividad enzimática y, por consiguiente, la disponibilidad de nutrientes. Los estudios demuestran que el uso de enzimas de fúngicas puede aumentar el valor nutritivo de los alimentos y mejorar la digestibilidad de los nutrientes, lo que refleja la eficiência productiva, lo que representa un ahorro en los costes de producción y beneficios para el medio ambiente, sin embargo, es necessário evaluarel uso de dietas con alimento alternativo expresión regional. Descriptores: Aditivos zootécnicos; La actividad enzimática; Polisacáridos no amiláceos.Objetivou-se nesta revisão abordar sobre enzimas fúngicas e seus efeitos em dietas com alimentos alternativos para frangos de crescimento lento. A alimentação representa maior parte do custo total de produção e para reduzir os gastos e aumentar o lucro do produtor têm sido pesquisados alimentos alternativos, como a torta de babaçu, a torta de dendê e o bagaço de mandioca, que demonstram potencial de utilização na alimentação de frangos caipira, no entanto, com limitação de uso, devido os diferentes teores de fibra. Os polissacarídeos não amiláceos dificultam o acesso das enzimas digestíveis sobre o alimento, diminuindo a digestibilidade dos nutrientes. Para minimizar esse efeito, têm sido suplementados enzimas exógenas nas dietas das aves. Várias fontes podem originar esses aditivos, sendo a maioria adquirida por meio dos processos fermentativos. A temperatura, o pH, a concentração do substrato e a composição dos ingredientes são fatores que influenciam a ação enzimática e, consequentemente, a disponibilidade dos nutrientes. O uso das enzimas fúngicas pode aumentar o valor nutricional do alimento e melhorar a digestibilidade dos nutrientes, refletindo na eficiência produtiva, representando economia no custo de produção e benefícios ao meio ambiente, todavia, torna-se necessário avaliar o uso em dietas com alimentos alternativos de expressão regional

Gall-forming insect attack patterns: a test of the Plant Vigor and the Resource Concentration Hypotheses

We tested the following two hypotheses to investigate the attack patterns by gall-inducing insects on their host plant Eriotheca pubescens: (i) vigorous modules are more often attacked by galling insects; and (ii) E. pubescens trees associated with a higher density of co-specific individuals have a higher gall abundance. We collected terminal branches from the host plant to measure their module lengths and gall richness and abundance and determined the E. pubescens densities in a 5m radius around the focal individual. There was a higher availability of short branches. Among the four gall morphotypes, two preferred the higher branches, and the other two morphotypes had no shoot length preference. Gall attack did not present a relationship with the host plant density. Thus, the vigor of E. pubescens was a determining factor only for some gall morphotypes. In contrast, the resource concentration hypothesis was not important at an intraspecific level for gall attack in this system

Caracterização física de frutos e putâmens e taxa de ataque por Carmenta sp. a pequizeiros (Caryocar brasiliense Camb.) no norte de Minas Gerais

O pequizeiro é uma espécie nativa do cerrado brasileiro, cujos frutos, explorados de forma extrativista, têm grande importância econômica. O extenso período de oferta dos frutos do pequi, aliado à heterogeneidade das regiões produtoras levam a crer na existência de diferenças entre as suas características físicas. Dessa forma, este trabalho objetivou comparar as características físicas de frutos de pequizeiro coletados em três municípios do norte de Minas Gerais e verificar se a taxa de ataque por Carmenta sp. está diretamente relacionada com as características biométricas. Assim, foram marcados 10 indivíduos e coletados 20 frutos de cada árvore, em Montes Claros, Mirabela e Japonvar, totalizando 200 frutos por área. Foram determinados as variáveis físicas dos frutos e dos putâmens, o número de frutilhos, de putâmens e de sementes e a porcentagem de frutos e de putâmens intactos e danificados. Os resultados indicaram que há diferenças nas características físicas entre as localidades, possuindo a região de Japonvar os putâmens mais vigorosos e com menor taxa de ataque pela broca-do-pequizeiro. Além disso, a porcentagem de ataque por Carmenta sp. relacionou-se com a espessura da casca e o comprimento dos frutos nas localidades de Japonvar e Mirabela, respectivamente. As diferenças encontradas entre as localidades podem estar associadas às influências climáticas e edáficas das regiões, que podem ressaltar certos aspectos de sua composição genética

Transcription blockage by DNA damage in nucleotide excision repair-related neurological dysfunctions

Human genetic syndromes deficient in nucleotide excision repair (NER), such as xeroderma pigmentosum and Cockayne syndrome, may present neurological abnormalities and premature aging symptoms. Unrepaired endogenously generated DNA damage that hampers transcription is a strong candidate that contributes to the development of these severe effects in neuronal tissue. Endogenous lesions include those generated due to byproducts of cellular metabolisms, such as reactive oxygen species. This review presents much of the evidence on the mechanisms related to neurodegenerative processes associated with DNA damage responses. The primary focus is on the effects of the transcription machinery, including the accumulation of DNA•RNA hybrids (R-loops) that, in turn, influence DNA damage and repair metabolism. Moreover, several neuronal tissues present higher expression of long genes, a genomic subset more affected by DNA lesions, which may explain part of the neurological abnormalities in these patients. Also, neuronal tissues have different DNA repair capabilities that might result in different neurological consequences, as observed in patients and NER deficient animal models. The better understanding of how the accumulation of transcription blocking lesions can lead to neurological abnormalities and premature aging-like phenotypes may assist us in finding potential biomarkers and therapeutic targets that might improve the lives of these patients, as well as other neurological disorders in the general population.This work was supported under the International Collaboration Research Funding from São Paulo Research Foundation (FAPESP, SP, Brazil) and the Netherlands Organization for Scientific Research – NWO (Grant #2019/19435-3). Financial support was also received from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Grant #308868/2018-8) and Coordenação de Aperfeiçoamento de Pessoal do Ensino Superior (CAPES, Brasília, DF, Brazil, financial code 001)

Data from: Changes in tree and liana communities along a successional gradient in a tropical dry forest in south-eastern Brazil

We investigated changes in species composition and structure of tree and liana communities along a successional gradient in a seasonally dry tropical forest. There was a progressive increase in tree richness and all tree structural traits from early to late stages, as well as marked changes in tree species composition and dominance. This pattern is probably related to pasture management practices such as ploughing, which remove tree roots and preclude regeneration by resprouting. On the other hand, liana density decreased from intermediate to late stages, showing a negative correlation with tree density. The higher liana abundance in intermediate stage is probably due to a balanced availability of support and light availability, since these variables may show opposite trends during forest growth. Predicted succession models may represent extremes in a continuum of possible successional pathways strongly influenced by land use history, climate, soil type, and by the outcomes of tree–liana interactions

Data from: Changes in tree and liana communities along a successional gradient in a tropical dry forest in south-eastern Brazil

We investigated changes in species composition and structure of tree and liana communities along a successional gradient in a seasonally dry tropical forest. There was a progressive increase in tree richness and all tree structural traits from early to late stages, as well as marked changes in tree species composition and dominance. This pattern is probably related to pasture management practices such as ploughing, which remove tree roots and preclude regeneration by resprouting. On the other hand, liana density decreased from intermediate to late stages, showing a negative correlation with tree density. The higher liana abundance in intermediate stage is probably due to a balanced availability of support and light availability, since these variables may show opposite trends during forest growth. Predicted succession models may represent extremes in a continuum of possible successional pathways strongly influenced by land use history, climate, soil type, and by the outcomes of tree–liana interactions

Database for Dryad mata seca curated

Database for Dryad mata seca curate