Differential Responses of Yield and Shoot Traits of Five Tropical Grasses to N and Distance to Trees in Silvopastoral Systems

Light intensity and nitrogen (N) availability are important factors influencing the growth of C4 forage species. Trade-offs may occur in the adaptive responses of species to shading and N inputs, and functional shoot traits can help to explain the consequences of these responses for species performance. Our objective was to gain understanding of the mechanisms between traits of five C4 perennial grasses determining above-ground dry matter yield (DMY) when both resources, light and N, vary. Forage grasses were grown in six shading conditions (full sunlight vs. five positions between Eucalyptus dunnii rows) with two N levels (0 vs. 300 kg N ha-1year-1) and clipped when the canopy reached 95% light interception. Path analysis was used to explore the relationship between DMY, shading levels, N nutrition index and shoot traits. Dry matter yield increased between 126 to 569 g dry matter m-2 with N fertilization. Nitrogen nutrition index was the most important predictor for determining DMY followed by shading level. Increased shading reduced DMY by 9.5 g DM m- ² for each 1% of increase in shading. DMY was also modulated by shoot traits such as specific leaf area and leaf area index, but with different responses according to species, highlighting different strategies to cope with changes in light and N availability

Procedimento de operação, manutenção e verificação de centrífuga JOUAN refrigerada.

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Resposta da produção de matéria seca do meloeiro à omissão de micronutrientes em um solo de Juazeiro - BA.

O trabalho teve como objetivo avaliar o efeito da omissão de B, Cu, Fe, Mn e Zn em plantas de melão (Cucumis melo L.) cultivadas em vasos contendo um solo argiloso de Juazeiro-BA, em ambiente protegido. Foram testados sete tratamentos: completo, testemunha, omissão de B, de Cu, de Fe, de Mn ou de Zn, dispostos no delineamento inteiramente casualizado, com quatro repetições. Avaliou-se o peso da matéria seca da parte aérea e das raízes aos 55 dias após a emergência das plantas. A omissão de Cu e Zn, provocou uma redução significativa na produção de matéria seca da parte aérea. Não houve efeito dos tratamentos sobre a matéria seca das raízes.Suplemento. Edição de Resumos expandidos e palestras do 43. Congresso Brasileiro de Olericultura, Recife, jul. 2003

Análise genética entre acessos de Oenocarpus mapora (Arecaceae) de hábito cespitoso e solitário.

A bacaby ou Oenocarpus mapora é uma palmeira considerada potencial para a domesticação devido às suas características comerciais de seu fruto e palmito. A espécie tem hábito predominantemente cespitoso, mas palmeiras de hábito solitário já foram descritas. O banco de germoplasma (BAG) do complexo Oenocarpus/Jessenia da Embrapa Amazônia Oriental possui em seu acervo uma amostra de materiais do tipo solitário de O. mapora coletados no noroeste paraense. Para veriicar a diversidade genética desse grupo no BAG e sua proximidade genética com materiais de hábito cespitoso, foram utilizados 18 indivíduos do tipo solitário para serem comparados com 1γ indivíduos do tipo cespitoso coletados em Itacoatiara (Aε) e oito coletados em Parintins (Aε), por meio de genotipagem com cinco locos microssatélites. A análise descritiva mostrou que há variabilidade genética dentro do grupo do tipo solitário, com H E = 0,7λ, variação que foi maior que a dos grupos de hábito cespitoso. A análise com AεOVA demonstrou grande diferenciação entre os grupos, com γβ,γη% de variação genética entre grupos. A distância genética par a par com base em FST mostrou que houve diferença significativa entre os grupos, e que o grupo do tipo solitário teve mais proximidade genética com um dos grupos do tipo cespitoso, do que entre os grupos do tipo cespitoso, indicando que o material pode ser utilizado em programas de melhoramento

Susceptibility of Hypsipyla grandella (Lepidoptera: Pyralidae) to Bacillus thuringiensis strains.

Na publicação: Rose Gomes Monnerat

The Oral-Vascular-Pulmonary Infection Route:a Pathogenic Mechanism Linking Oral Health Status to Acute and Post-Acute COVID-19

Purpose of Review: In recent years, much attention has focused on the role of poor oral health in the development or worsening of systemic diseases, including COVID-19. The mouth is an important site of cellular infection early in the disease course of COVID-19. We review how oral pathology, and specifically viral infection within the oral cavity, may mediate the disease severity and duration of COVID-19. In particular, the previously reported model of SARS-CoV-2 vascular delivery from the mouth to the lungs via the bloodstream is revisited.Recent Findings: We previously proposed that an oral-vascular-pulmonary route of infection could facilitate severe lung disease in COVID-19. This pathway could also explain the vital link between periodontitis and COVID-19 severity, including higher mortality risk. This model of pathogenesis is reconsidered in light of recent findings regarding the involvement of the mouth as a viral reservoir, and pathological processes in the blood, pulmonary vasculature, and elsewhere in the body. Oral dysbiosis in COVID-19 and the effect of oral hygiene in mitigating disease severity are discussed. The evidence for viral persistence in the mouth and intravascular viral passage from the mouth to the rest of the body via blood is also discussed in the context of post-acute COVID (long COVID).Summary: High viral load in the mouth and poor oral health status are associated with COVID-19 disease severity, increasing the risk of death. Pathophysiological links between viral activity in the mouth, oral health status, and disease outcome in the lungs and blood provide a rationale for further evaluation of the oral-vascular-systemic pathway in patients with acute COVID-19 and long COVID. The potential benefits of oral hygiene protocols and periodontal procedures in COVID-19 also warrant further investigation

The Oral-Vascular-Pulmonary Infection Route:a Pathogenic Mechanism Linking Oral Health Status to Acute and Post-Acute COVID-19

Purpose of Review: In recent years, much attention has focused on the role of poor oral health in the development or worsening of systemic diseases, including COVID-19. The mouth is an important site of cellular infection early in the disease course of COVID-19. We review how oral pathology, and specifically viral infection within the oral cavity, may mediate the disease severity and duration of COVID-19. In particular, the previously reported model of SARS-CoV-2 vascular delivery from the mouth to the lungs via the bloodstream is revisited.Recent Findings: We previously proposed that an oral-vascular-pulmonary route of infection could facilitate severe lung disease in COVID-19. This pathway could also explain the vital link between periodontitis and COVID-19 severity, including higher mortality risk. This model of pathogenesis is reconsidered in light of recent findings regarding the involvement of the mouth as a viral reservoir, and pathological processes in the blood, pulmonary vasculature, and elsewhere in the body. Oral dysbiosis in COVID-19 and the effect of oral hygiene in mitigating disease severity are discussed. The evidence for viral persistence in the mouth and intravascular viral passage from the mouth to the rest of the body via blood is also discussed in the context of post-acute COVID (long COVID).Summary: High viral load in the mouth and poor oral health status are associated with COVID-19 disease severity, increasing the risk of death. Pathophysiological links between viral activity in the mouth, oral health status, and disease outcome in the lungs and blood provide a rationale for further evaluation of the oral-vascular-systemic pathway in patients with acute COVID-19 and long COVID. The potential benefits of oral hygiene protocols and periodontal procedures in COVID-19 also warrant further investigation