13 research outputs found
Influence of stage of maturity on bromatological quality of corn forage
ABSTRACT -The objective of this study was to evaluate the effects of stalk/leaf ratio and the stage of maturity on the digestibility of the corn plant. Hybrids AG1051, AG4051, AG5011, DOW2B710, DOW2C577, DOW2A525, NB7315 and P30F90 were used, harvested at the one-half milk line (½ ML), three-quarters milk line (¾ ML) and black layer (BL) stages. A randomized block design was used in an 8 (hybrids) × 3 (stages of maturity) factorial design, with three replications. The means generated were used for grouping into high and low stalk/leaf ratio and a new analysis of variance was generated in a 2 × 3 (two groups and three stages of maturity) factorial design. The whole plant and its stalk, leaf, husk, cob and grain components were incubated in situ in the rumen of three cows for determination of degradability of dry matter and degradable neutral detergent fiber. Stalk/leaf ratio did not influence neutral detergent fiber content or the degradability of dry matter and neutral detergent fiber of any of the components, except for the cob, in which the high ratio group had greater degradable neutral detergent fiber contents. There was a reduction in the degradability of all the parts, except for the stalk and cob, and an increase in the neutral detergent fiber contents of the vegetative parts, except for the stalk. Unlike the vegetative components, the neutral detergent fiber contents of the whole plant decreased throughout the stages evaluated. For degradable neutral detergent fiber, there was a reduction in the whole plant and in its components. The advance of maturity reduces the quality of the vegetative components; however, this loss in the entire plant is moderated by grain filling. Forage quality depends more on the quality of the components than on their proportions in the dry matter
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
Influence of stage of maturity on bromatological quality of corn forage
The objective of this study was to evaluate the effects of stalk/leaf ratio and the stage of maturity on the digestibility of the corn plant. Hybrids AG1051, AG4051, AG5011, DOW2B710, DOW2C577, DOW2A525, NB7315 and P30F90 were used, harvested at the one-half milk line (½ ML), three-quarters milk line (¾ ML) and black layer (BL) stages. A randomized block design was used in an 8 (hybrids) × 3 (stages of maturity) factorial design, with three replications. The means generated were used for grouping into high and low stalk/leaf ratio and a new analysis of variance was generated in a 2 × 3 (two groups and three stages of maturity) factorial design. The whole plant and its stalk, leaf, husk, cob and grain components were incubated in situ in the rumen of three cows for determination of degradability of dry matter and degradable neutral detergent fiber. Stalk/leaf ratio did not influence neutral detergent fiber content or the degradability of dry matter and neutral detergent fiber of any of the components, except for the cob, in which the high ratio group had greater degradable neutral detergent fiber contents. There was a reduction in the degradability of all the parts, except for the stalk and cob, and an increase in the neutral detergent fiber contents of the vegetative parts, except for the stalk. Unlike the vegetative components, the neutral detergent fiber contents of the whole plant decreased throughout the stages evaluated. For degradable neutral detergent fiber, there was a reduction in the whole plant and in its components. The advance of maturity reduces the quality of the vegetative components; however, this loss in the entire plant is moderated by grain filling. Forage quality depends more on the quality of the components than on their proportions in the dry matter
NUTRIÇÃO E PRODUÇÃO DE MATÉRIA SECA DE MILHO SUBMETIDO A CALAGEM E ADUBAÇÃO SULFATADA MAIZE NUTRITION AND DRY MATTER YIELD UNDER LIMING AND SULFUR FERTILIZATION
<p style="text-align: justify !important;"><span><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span>A calagem é uma prática indispensável para obtenção de altos rendimentos das culturas, em solos tropicais ácidos. Objetivou-se avaliar a nutrição e produção de matéria seca de milho, em solo submetido a calagem estimada por três métodos de cálculo e adubação sulfatada. O experimento foi desenvolvido em casa-de-vegetação, em tubos de PVC, com uma planta por tubo. Utilizou-se Latossolo Vermelho distrófico (LVd), sob vegetação nativa. Foi aplicado calcário dolomítico, tipo filler, nas doses de 4,2 Mg ha</span></span></span></span></span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span>-1</span></span></span></span></span></sup></span></span><span style="color: #000000;"><span><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span>; 6,7 Mg ha</span></span></span></span></span></span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span lang="pt-BR"><span><span><span>-1</span></span></span></span></span></span></sup></span></span><span style="color: #000000;"><span><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span>; e 8,0 Mg ha</span></span></span></span></span></span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span lang="pt-BR"><span><span><span>-1</span></span></span></span></span></span></sup></span></span><span style="color: #000000;"><span><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span>, calculadas pelo método do alumínio trocável, cálcio e magnésio; método da elevação da saturação por bases; e método do tampão SMP, respectivamente, além do tratamento sem aplicação de calcário, combinados com três doses de S (10 mg dm</span></span></span></span></span></span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span lang="pt-BR"><span><span><span>-3</span></span></span></span></span></span></sup></span></span><span style="color: #000000;"><span><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span>, 30 mg dm</span></span></span></span></span></span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span lang="pt-BR"><span><span><span>-3</span></span></span></span></span></span></sup></span></span><span style="color: #000000;"><span><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span> e 60 mg dm</span></span></span></span></span></span></span><span style="color: #000000;"><span><sup><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span lang="pt-BR"><span><span><span>-3</span></span></span></span></span></span></sup></span></span><span style="color: #000000;"><span><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span>), mais o tratamento sem adição de enxofre. As plantas de milho foram colhidas aos 45 dias após a semeadura, sendo separada a parte aérea do sistema radicular. O método mais eficiente de recomendação de calagem para o milho foi o método da elevação da saturação por bases. A aplicação de doses de enxofre não teve efeito no desenvolvimento do milho, até o estádio avaliado.</span></span></span></span></span></span></span></p> <p class="western"><span style="color: #000000;"><span><span style="font-family: Verdana, Arial, Helvetica, sans-serif;"><span style="font-size: xx-small;"><span><span><span><br />PALAVRAS-CHAVE: Zea mayz; acidez do solo; matéria seca; desenvolvimento radicular.</span></span></span></span></span></span></span><span style="color: #000000;"><span><span style="font-family: Verdana, sans-serif;"><span style="font-size: x-small;"><span> </span></span></span></span></span></p><br />Liming is essential for obtaining high yield levels in tropical acid soils. The objective of this study was to evaluate maize nutrition and dry matter yield in soil under liming estimated by three calculation methods and sulfur fertilization. The experiment was carried out under greenhouse conditions, in PVC cylinders, by using one plant per cylinder. Filler dolomite lime was added to an Oxisol collected from native forest, at the 4.2 Mg ha-1, 6.7 Mg ha-1, and 8.0 Mg ha-1 doses, respectively calculated by the exchangeable aluminum, magnesium, and calcium method; base saturation method; and SMP buffer method, combined with three sulfur doses (10 mg dm-3, 30 mg dm-3, and 60 mg dm-3). Control treatments without lime or sulfur were also included. Maize plants were harvested at 45 days after sowing and divided into shoots and roots. The most efficient lime recommendation method for maize was the base saturation method. The application of sulfur doses did not affect the maize development up to the evaluated stage.<br /><br />KEY-WORDS: Zea mayz; soil acidity; dry mass; root development
Aspectos ecológicos de flebotomíneos (Diptera: Psychodidae) em área urbana do município de Ponta Porã, Estado de Mato Grosso do Sul Ecological aspects of Phlebotomines (Diptera: Psychodidae) in the urban area of Ponta Porã municipality, State of Mato Grosso do Sul, Brazil
INTRODUÇÃO: Neste trabalho, realizou-se análise faunística de flebotomíneos e levantamento dos índices de infestações (intra e peridomicílio) na área urbana de Ponta Porã/MS, de setembro de 2005 a agosto de 2007. MÉTODOS: As coletas foram realizadas com armadilhas automáticas luminosas do tipo CDC, instaladas mensalmente durante três noites consecutivas, das 18h às 6h. RESULTADOS: Foram capturados 3.946 flebotomíneos, pertencentes a oito espécies, com amplo predomínio de Lutzomyia longipalpis, apresentando os maiores índices de frequência, constância, abundância e dominância. Do total capturado, 82,9% foram de machos e 17,1% fêmeas. A média mensal de machos capturados (136,29 ± 152,01) foi significativamente maior que o número médio de fêmeas. Embora não tenham sido constatadas diferenças significativas, verificou-se que a incidência média de flebotomíneos no peridomicílio foi maior do que no intradomicílio. Uma análise de correlação revelou que três variáveis ambientais medidas (temperatura máxima, umidade relativa e precipitação pluviométrica), correlacionaram-se positivamente de forma significativa com a abundância de flebotomíneos. CONCLUSÕES: Constitui-se motivo de alerta a predominância de L. longipalpis no município de Ponta Porã, visto que implica na possibilidade de surtos de leishmaniose visceral na área, pois essa espécie é o principal vetor da Leishmania chagasi no estado bem como em outras localidades do Brasil.<br>INTRODUCTION: The aim of this study was to carry out an analysis of urban phlebotomine fauna and a survey of infestations (intradomiciliary and peridomiciliary) in Ponta Porã municipality State of Mato Grosso do Sul. METHODS: Sand flies were collected with automatic CDC light traps, installed monthly on three consecutive nights, from 18h to 6h, from September 2005 to September 2007. RESULTS: A total of 3,946 phlebotomines, representing eight species, were captured, among which was a large predominance of Lutzomyia longipalpis, presenting high indexes of frequency, constancy, abundance and dominance. Of the total, 82.9% were males and 17.1% females. The monthly average number (136.29 ± 152.01) of males captured being, much larger than that of females. Although the average number of phlebotomines in the intradomicile was much larger than that in the peridomicile, there was no significant statistical difference. A positive correlation was found between the abundance of phlebotomines and the average daily maximum temperature, precipitation and relative atmospheric humidity. CONCLUSIONS: The predominance of Lutzomyia longipalpis in Ponta Porã municipality is a reason for concern as regards the possibility of outbreaks of visceral leishmaniasis in the area, because this species is the main Leishmania chagasi vector not only in Mato Grosso do Sul but also nationwide