Viabilidade Técnica E Econômica Da Irrigação Localizada Do Cafeeiro, Nas Condições Climáticas Do Planalto De Araxá, Mg

In the region of Araxá highlands, the economical production of coffee is traditionally made without irrigation. Notwithstanding in recent years, with climate change, water deficit of 150 mm have been verified, affecting the vegetative and productive development of the culture. Within this context, the aim of this study was to evaluate supplementary irrigation to increase production and profitability of the coffee grown in the highlands of Araxá, compared to a non-irrigated and irrigated cultivation throughout the year. The work was implemented in Araxá, Minas Gerais in 2006 and carried out throughout the period of nine years. Different periods of water stress (from April to November) were evaluated, compared with irrigation throughout the year and the witness. After 6 consecutive harvests, it can be concluded that supplemental irrigation promoted an increased productivity in the coffee grown under the conditions of the Araxá Plateau, especially in years of drought. With regard to economic performance, the process of irrigation applied throughout the year promoted profits of 279% (R$/ha year-1) compared to the treatment without irrigation. © 2016, Editora UFLA. All rights reserved.11334735

Infrared thermography as a tool in welfare assessment of equines handled in paddock and stall

ABSTRACT This study aims to describe the effects of stabling on thermographic characteristics of adult equine limbs, to compare the level of animal welfare between horses kept loose and those under continuous stabling and to investigate whether the Infrared Thermography (IRT) can be an effective tool to evaluate the welfare of equines. 24 gelding horses of Brazilian Sport Horse breed, aged between 5 and 9 years and weighing 500 ± 50kg were used in a 6-week trial. They were divided into 2 groups: 1) Paddock - equines kept in paddocks and ridden exclusively on urban patrol; 2) Stall - animals that ridden exclusively on urban patrol, but were kept in continuous stabling, housed in 12m² with concrete and bedless stables. Every animal was evaluated once a week over six weeks. Animal behavior and temperature of the eyes and distal extremities of the limbs as well as blood samples were collected. The confined horses showed stereotyped behavior and higher serum cortisol, indicating lower animal welfare when compared to those managed in a pasture. Limb IRT showed predictive potential for identifying chronic stress as the discriminating analysis showed 74.5% hits while eye temperature was not efficient for this purpose

Arabidopsis thaliana as a model host for Brevipalpus mite-transmitted viruses

ABSTRACT: Brevipalpus-transmitted viruses (BTV) are a taxonomically diverse group of plant viruses which severely affect a number of major crops. Members of the group can be sub-classified into cytoplasmic (BTV-C) or nuclear type (BTV-N) according to the accumulation sites of virions in the infected plant cells. Both types of BTV produce only local infections near the point of inoculation by viruliferous mites. Features of BTV-plant interactions such as the failure of systemic spread in their natural hosts are poorly understood. In this study we evaluated Arabidopsis thaliana, a model plant commonly used for the study of plant-virus interactions, as an alternative host for BTV. Infection of Arabidopsis with the BTV-N Coffee ringspot virus and Clerodendrum chlorotic spot virus, and the BTV-C Solanum violaefolium ringspot virus, were mediated by viruliferous Brevipalpus mites collected in the wild. Upon infestation, local lesions appeared in 7 to 10 days on leaves of, at least, 80 % of the assayed plants. Presence of viral particles and characteristic cytopathic effects were detected by transmission electron microscopy (TEM) and the viral identities confirmed by specific reverse-transcriptase polymerase chain reaction (RT-PCR) and further amplicon sequencing. The high infection rate and reproducibility of symptoms of the three different viruses assayed validate A. thaliana as a feasible alternative experimental host for BTV

Acúmulo de carbono em Latossolo adubado com dejeto líquido de suínos e cultivado em plantio direto

O objetivo deste trabalho foi estimar taxas de acúmulo de C orgânico em Latossolo Vermelho adubado com adubo solúvel e dejeto líquido de suíno e cultivado em plantio direto. O experimento foi conduzido em Campos Novos, SC, e os seguintes tratamentos foram aplicados anualmente: sem adubação; adubo solúvel; 25 m3 ha-1 de dejeto líquido + adubo solúvel; e doses de 25, 50, 100 e 200 m3 ha-1 de dejeto líquido. Foram determinados: os estoques de C orgânico (CO) na camada de 0-20 cm do solo; a adição de C pela fitomassa dos cultivos e pelo dejeto líquido de suíno; as taxas anuais de fixação de C; e os coeficientes de humificação (k1) e de mineralização (k2) de CO do solo. As taxas de fixação de C real e aparente aumentaram de acordo com as doses de dejeto, tendo variado de 0,6 a 1,7 e de 0,05 a 1,0 Mg ha-1 por ano, respectivamente. Os coeficientes k1 e k2 foram 0,17 e 0,011, respectivamente, enquanto o aporte de C requerido para manter o estoque inicial de CO do solo é de 4,14 Mg ha-1 por ano. O dejeto líquido de suíno aplicado anualmente em Latossolo Vermelho cultivado com a sucessão milho-aveia-preta em plantio direto aumenta o CO do solo em doses de até 200 m3 ha-1

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications 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, 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