Mineralization of sheep manure and its influence on lettuce production

Diversos resíduos orgânicos são utilizados na agricultura sem o adequado conhecimento da sua dinâmica de mineralização. Avaliou-se a mineralização de esterco de ovinos e sua influência na produção de alface. Utilizou-se o delineamento experimental de blocos ao acaso com três repetições. Foram utilizadas 25 t ha-1 como dose de esterco para cada um dos seguintes tratamentos: 1) esterco de ovinos que se alimentaram de feno de mandioca (PAM); 2) esterco de ovinos que se alimentaram de subproduto de ervilha (ERV); 3) esterco de ovinos que se alimentaram de feno de capim coast-cross (FCC); 4) esterco de ovinos que se alimentaram de subproduto de saccharina (SAC) e 5) solo sem aplicação de esterco (testemunha). Foi determinada semanalmente a respiração basal do solo, utilizada como indicador de mineralização da matéria orgânica. A massa fresca de alface foi avaliada como medida de produção. Os tratamentos ERV, FCC e SAC apresentaram ganhos de massa fresca na ordem de 68, 65 e 62% em relação à testemunha e de 43, 39 e 33% em relação ao PAM, respectivamente. A produção menor promovida pelo PAM, em relação às demais, pode ser explicada pela forma de mineralização da matéria orgânica que apresentou elevada respiração microbiana cinco dias após o transplantio, com acentuado declínio, nas medições subseqüentes, ao longo do ciclo da cultura. Os demais tratamentos apresentaram mineralização sincronizada com conseqüente aumento na produção de massa fresca. ____________________________________________________________________________________________________________ ABSTRACTSeveral organic wastes are used in agriculture with no precise knowledge about the mineralization dynamics of these materials. In this study the sheep manure mineralization and its influence on the lettuce production was evaluated. A randomized block design with three replications was used. Five treatments were studied using 25 t ha-1 as dose of manure: 1) sheep manure obtained from animals fed with cassava straw (PAM); 2) sheep manure obtained from animals fed with residue of pea crop (ERV); 3) sheep manure obtained from animals fed with Coast-Cross hay (FCC), 4) sheep manure obtained from animals fed with saccharin residue (SAC) and 5) soil without application of manure (control). Weekly the basal respiration was determined and used as an indicator of organic matter mineralization. Lettuce fresh mass was evaluated as a measure of production. Treatments ERV, FCC and SAC showed superior weight gains of 68, 65 and 62% compared to the control and 43, 39 and 33% compared to MAP, respectively. Lower production promoted by the MAP in relation to the other treatments can be explained by organic matter mineralization that showed a high microbial respiration five days after transplanting, with marked decline in subsequent measurements during the crop cycle. The other systems showed mineralization synchronized with the production increase of lettuce fresh mass

Effects of Glyphosate and its Formulation, Roundup, on Reproduction in Zebrafish (Danio rerio)

This is an open access article that is freely available in ORE or from the publisher's web site. Please cite the published version.Copyright © 2014 American Chemical SocietyRoundup and its active ingredient glyphosate are among the most widely used herbicides worldwide and may contaminate surface waters. Research suggests both Roundup and glyphosate induce oxidative stress in fish and may also cause reproductive toxicity in mammalian systems. We aimed to investigate the reproductive effects of Roundup and glyphosate in fish and the potential associated mechanisms of toxicity. To do this, we conducted a 21-day exposure of breeding zebrafish (Danio rerio) to 0.01, 0.5, and 10 mg/L (glyphosate acid equivalent) Roundup and 10 mg/L glyphosate. 10 mg/L glyphosate reduced egg production but not fertilization rate in breeding colonies. Both 10 mg/L Roundup and glyphosate increased early stage embryo mortalities and premature hatching. However, exposure during embryogenesis alone did not increase embryo mortality, suggesting that this effect was caused primarily by exposure during gametogenesis. Transcript profiling of the gonads revealed 10 mg/L Roundup and glyphosate induced changes in the expression of cyp19a1 and esr1 in the ovary and hsd3b2, cat, and sod1 in the testis. Our results demonstrate that these chemicals cause reproductive toxicity in zebrafish, although only at high concentrations unlikely to occur in the environment, and likely mechanisms of toxicity include disruption of the steroidogenic biosynthesis pathway and oxidative stress.Natural Environment Research Counci

The potential for dementia prevention in Brazil: a population attributable fraction calculation for 14 modifiable risk factors

Background: The Lancet Commission on dementia prevention, intervention, and care 2024 updated the list of modifiable risk factors to include 14 factors. The potential for dementia prevention seems to be greater in low- and middle-income countries (LMIC) due to the higher prevalence of these factors. This study aims to provide the first LMIC figure for the potential for dementia prevention in Brazil attributed to 14 modifiable risk factors. Methods: Data was retrieved from 9949 participants aged 50 years or older from the nationally representative second wave of the Brazilian Longitudinal Study of Aging (ELSI-Brazil) conducted between 2019 and 2021. The prevalence of modifiable risk factors was estimated, and principal component analysis was used to account for factor communalities. Overall and individual population attributable fractions (PAF) were calculated using relative risks from the 2024 Lancet Commission report. Stratified analyses by sex, race, and Brazilian macro regions were performed to assess disparities in dementia risk. Findings: The overall PAF for the 14 modifiable risk factors was 59.5% (95% CI = 58.5–60.5). The three risk factors with the highest PAFs were less education (9.5%, 95% CI = 8.9–10.1), untreated visual loss (9.2%, 95% CI = 8.6–9.8), and midlife depression (6.3%, 95% CI = 5.8–6.8). The overall PAF was similar across race and region but was higher among women (61.1%, 95% CI = 59.9–62.4) compared to men (58.2%, 95% CI = 56.7–59.8). Interpretation: Almost 60% of dementia cases in Brazil could potentially be prevented by addressing 14 modifiable risk factors. Public health strategies could further reduce the dementia burden in Brazil. Funding: CKS, PC, and CPF received productivity fellowships from the National Council for Scientific and Technological Development (CNPq). ELSI-Brazil was supported by the Brazilian Ministry of Health: DECIT/SCTIE (Grants: 404965/2012-1 and TED 28/2017); COPID/DECIV/SAPS (Grants: 20836, 22566, 23700, 25560, 25552, and 27510)

Fabaceae e Myrtaceae arbustivas e arbóreas do bioma Pampa: restauração ecológica e usos econômicos.

Devido às exigências da Lei de Proteção da Vegetação Nativa (popularmente conhecido como Novo Código Florestal), é iminente a busca e ampla disponibilização por estratégias e espécies que relacionem a restauração ecológica com o uso econômico e geração de renda por parte da agricultura familiar. Dentre as espécies arbustivas e arbóreas de grande utilização cotidiana por agricultores no bioma Pampa, destacam-se aquelas das famílias Fabaceae e Myrtaceae, que apresentam ampla gama de usos no meio rural, além de possuírem potencial para restauração ecológica. O objetivo do trabalho foi realizar o levantamento de espécies das famílias Fabaceae e Myrtaceae para restauração e uso econômico e proceder a um comparativo entre estas famílias. Foram avaliadas 38 espécies de arbustos e árvores nativas do bioma Pampa das famílias Fabaceae (20 espécies) e Myrtaceae (18 espécies). Os três usos de maior frequência foram: ornamental, madeireiro e lenha para ambas as famílias. Este trabalho agrega informações que podem incentivar o uso destas espécies para diversos fins econômicos, agregando valor à propriedade rural e ao mesmo tempo adequando o agricultor à legislação vigente.Suplemento. Edição dos Anais do 10 Congresso Brasileiro de Agroecologia; 6 Congresso Latino-americano de Agroecologia; 5 Seminário de Agroecologia do Distrito Federal e Entorno, Brasília, DF, set. 2017

Desempenho produtivo de novas introduções de cultivares resistentes a doenças (PIWI) na Serra Gaúcha.

As condições climáticas do sul do Brasil são favoráveis a patógenos fúngicos que reduzem a produtividade e a qualidade da uva em vinhedos comerciais. A seleção assistida por marcadores moleculares combinada com retrocruzamentos múltiplos com variedades Vitis vinifera L. permitiu o desenvolvimento de cultivares híbridas resistentes com elevada qualidade enológica, denominadas Pilzwiderstandsfähigen (PIWIs), sigla alemã para “resistente a fungos”