Maurílio F. de Oliveira

Weed suppression and organic green corn production in no tillage system

O sombreamento do solo com cobertura morta proporciona reducao na germinacao das sementes e diminuicao da populacao de plantas daninhas, possibilitando as plantas da cultura de interesse se desenvolverem sob efeito de menor competicao inicial. Dessa forma, objetivou-se neste trabalho investigar o efeito do cultivo de leguminosas na evolucao da comunidade de plantas daninhas na cultura do milho-verde cultivado em sucessao, num sistema orgânico. O ensaio foi realizado em delineamento em blocos ao acaso, com parcelas subdivididas e quatro repeticoes. Inicialmente, houve o plantio das leguminosas: feijao-de-porco (Canavalia ensiformes), guandu (Cajanus cajan), mucuna-preta (Mucuna aterrinum), mucuna-ana (Mucuna deeringiana) e crotalaria (Crotalaria juncea); foi mantida uma testemunha sem cultivo em pousio. Anteriormente ao cultivo do milho, foi avaliada a producao de materia seca de cada especie de leguminosa. Em seguida, apos a rocada das leguminosas foi semeado sobre a palhada o milho, cultivar HTMV 02. A amostragem das plantas daninhas foi realizada aos 15 e 30 dias apos a emergencia do milho, lancando-se de forma aleatoria sobre cada parcela um quadro de 50 x 50 cm. As plantas daninhas dentro do quadro foram identificadas, pesadas e contadas por especie, sendo posteriormente colocadas em estufa a 65 oC, por 72 horas, para determinacao da materia seca. As palhadas da mucuna-preta e da crotalaria proporcionaram maior reducao de materia seca e populacao das plantas daninhas. A maior produtividade de espigas comerciais de milho-verde foi obtida na area de palhada de mucuna-preta e crotalaria.

Efeito da palha e da mistura atrazine e metolachlor no controle de plantas daninhas na cultura do milho, em sistema de plantio direto

The objective of this work was to study the effect of corn plant residue and mixture of atrazine plus metolachlor on weed control in no-till corn system. This experiment was performed in an Oxisol, and the weed desiccation was done using glyphosate, 15 days before planting. The experimen- tal design was a randomized block, with three replications. Before corn planting, five levels of corn plant residues (0, 3, 6, 9 e 12 t ha -1 ) were equally distributed in the plots. Two treatments were applied in subplots after corn planting: one without herbicide and the other one using the commercial mixture of atrazine plus metolachlor (1,200 + 1,800 g ha -1 ). Different weed species were evaluated, at 26 and 41 days after planting. The total grass weeds number was significantly affected by the plant residue levels, independently of herbicide treatments and of evaluation period. The herbicide did not show a significant effect in the first evaluation period. However, in the second evaluation period, the herbicide reduced about 53% the total number of weeds compared to the plots without herbicide. It was verified that in the herbicide absence the total population of weeds were significantly higher in the second evaluation period. However, in the herbicide presence there was no significant difference in the total population of weeds between the two evaluated periods.

Lixiviação de flumioxazin e metribuzin em dois solos em condições de laboratório

This study was conducted to evaluate leaching of herbicides flumioxazin and metribuzin under greenhouse conditions, in a Utisol and a Oxisol (collected in two differents agricultural regions in the state of Minas Gerais) soils in two moisture conditions (wet and dry soil). Simulation of rainfall ( 45 mm and 90 mm) was done after application of flumioxazin (60 g/ha) and metribuzin (384 g/ha) in columns containing two soils under wet and dry conditions. Flumioxazin did not leach beyond 5 cm from the surface when applied in the sandy-loam soil. In the sandy soil, this herbicide reached a depth of 10 cm from the surface in the column. Metribuzin presented great mobility in both soils and moisture conditions, reaching depth of 20 cm in wet sandy-loam soil and 45 cm in dry sandy soil.This study was conducted to evaluate leaching of herbicides flumioxazin and metribuzin under greenhouse conditions, in a Utisol and a Oxisol (collected in two differents agricultural regions in the state of Minas Gerais) soils in two moisture conditions (wet and dry soil). Simulation of rainfall ( 45 mm and 90 mm) was done after application of flumioxazin (60 g/ha) and metribuzin (384 g/ha) in columns containing two soils under wet and dry conditions. Flumioxazin did not leach beyond 5 cm from the surface when applied in the sandy-loam soil. In the sandy soil, this herbicide reached a depth of 10 cm from the surface in the column. Metribuzin presented great mobility in both soils and moisture conditions, reaching depth of 20 cm in wet sandy-loam soil and 45 cm in dry sandy soil.

Atividade da acetolactato sintase de plantas de milho e de amendoim-bravo (Euphorbia heterophylla) resistentes e suscetíveis ao imazaquin

O amendoim-bravo, (Euphorbia heterophylla) e uma importante planta daninha em mais de 56 paises, inclusive no Brasil, onde tem sido relatado o aparecimento de populacoes resistentes aos herbicidas inibidores da acetolactato sintase (ALS). O objetivo do trabalho foi avaliar o efeito do herbicida imazaquin na atividade da ALS extraida das plantas de milho e amendoim-bravo, resistentes e suscetiveis ao produto. Sementes de dois genotipos de milho e varios biotipos de amendoim-bravo provenientes de diferentes regioes agricolas brasileiras foram cultivadas em casa de vegetacao por 21 dias. A atividade da ALS extraida das folhas das plantas foi determinada na presenca de doses de imazaquin. A etapa de purificacao da enzima foi substituida por uma centrifugacao de 2.800 rpm por dois minutos. Equacoes de regressao linear para absorbância em funcao do log da concentracao de imazaquin foram ajustadas para cada populacao, visando obtencao do I50. A dose de imazaquin necessaria para inibir 50% da atividade da ALS (I50) na variedade de milho Pioneer 3162 IR (I50 260 µM) foi 4.333 vezes maior que a dose requerida pela BRS 473 (0,06 µM), a qual e suscetivel ao imazaquin. Os biotipos de amendoim-bravo provenientes do Rio Grande do Sul apresentaram valores de I50 de 1.961,3 e 13,8 mM para os biotipos resistentes e suscetiveis, respectivamente. Os biotipos provenientes de Cafelândia e Maringa (PR) e Vicosa (MG) apresentaram valores de I50 maiores que 5.000 mM para os biotipos resistentes e maiores que 1.000 mM para os suscetiveis. O amendoim-bravo coletado na Embrapa Milho e Sorgo, em area que nunca foi tratada com herbicidas inibidores da ALS, apresentou I50 de 12,2 mM. Conclui-se que a medida in vitro da atividade da ALS e um metodo sensivel para determinacao da presenca de biotipos resistentes a acao do herbicida imazaquin. A etapa de purificacao da ALS pode ser substituida por um metodo que envolve uma rapida centrifugacao.

Atividade dos herbicidas flumioxazin e metribuzin em diferentes solos

The activity of flumioxazin and metribuzin herbicides was evaluated in four different soils using washed sand. The soils were: an Utisol collected in an agricultural region in the State of Minas Gerais and an Oxisol collected in three different agricultural regions; two in the State of Minas Gerais and one in the State of Mato Grosso do Sul. Ten rates of each herbicide were evaluated for each soil in pots, with five replications per treatment. Herbicide rates tested and the amount of soil per pot varied with the type of soil being evaluated. The soil moisture content was maintained at soil moisture capacity with simulated rainfalls. The soil type, its physical-chemical properties, and mainly its organic carbon content affected the activity rate of both herbicides. For flumioxazin, the soils with the highest organic carbon content presented the highest values of I50, which means, greater adsorption of the herbicide. Meanwhile, for metribuzin, the activity rate was affected by the pH and the organic carbon content of the different soils tested. The results of this study sug gest that the recomendations for use of herbicides should vary according to the type of soil.

Mobilidade do dimethenamid em diferentes solos

The mobility of herbicide dimethenamid in sand and soils from Monte Santo (sandy clay loam), Sete Lagoas (clay) and Tres Marias (loamy sand) - MG was evaluated in greenhouse conditions using bioassay methodology. The herbicide was applied to the soil at a dose of 1.125 kg i.a. ha-1. After product application, a rainfall (45 and 90 mm) was simulated on top of column containing the samples. The experimental layout was randomized block design with 4 replications in a factorial scheme. The dimethenamid was strongly leached in sand substract. In the Tres Marias soil dimethenamid achieved 10 to 15 cm depth with 45 mm rainfall simulation and 20 to 30 cm when 90 mm rainfall was used. Monte Santo and Sete Lagoas soils had a similar leaching behavior remaining in the first 5 cm of column.

Tolerance of corn hybrids to nicosulfuron

ABSTRACT – This experiment was carried out at Embrapa Milho e Sorgo Experimental Station,Sete Lagoas-MG, Brazil, to evaluate the tolerance of corn hybrids BRS 3060, 3101, 2114 and2110 to different rates of nicosulfuron, during the growing season of 1998/1999. Corn plantdensity was 50,000 plants per hectare and nicosulfuron rates were 50, 60 and 70 g a.i. ha -1 plusone control treatment, without herbicide. However, this treatment was kept weed free. Theexperiment design was a randomized block with 3 replications in 4 x 4 factorial design. Nicosulfuronwas sprayed at the stage of 4 to 6 leaves, or 20 days after crop emergence. Phytotoxicity evaluationwas at 7, 14 and 21 days after nicosulfuron application. Only BRS 3060 presented very lowtolerance to nicosulfuron in the period of 14 and 21 days after herbicide application but grainyield was not affected. The results showed that nicosulfuron can be sprayed to control weeds incorn hybrids BRS 3060, 3101, 2114 and 2110, at the rates of 50 and 70 g i.a. ha

AB0881 Biologic Disease Modifying Anti-Rheumatic Drug Use in the Treatment of Juvenile Idiopathic Arthritis: Data from the Rheumatic Diseases Portuguese Register, Reuma.Pt

Background The Portuguese Society of Rheumatology developed the Rheumatic Diseases Portuguese Register (Reuma.pt) encompassing also Juvenile Idiopathic Arthritis patients followed by rheumatologists and pediatricians. Objectives 1. To obtain an overview of biological agents use in Portuguese children with JIA. 2. To assess the effectiveness and safety of biological therapy at 6 months and 1 year of treatment. Methods We retrieved data from Reuma.pt, until December 2013. We collected baseline patient and disease characteristics of patients with JIA who started treatment with biological agents. Follow-up data were analyzed and are presented at 6 months and 1 year. Disease activity was assessed using the number of active joints, ESR and CHAQ. Results 812 patients with JIA,227 received biological therapy.The mean age at disease onset of patients treated with biologic DMARDs was 6.9±4.7years and the mean age for starting biological therapy was 16.1±9.4years. The most common JIA categories were polyarticular RF negative (23.3%), polyarticular RF+(17.5%) and extended oligoarticular (16.0%).The median duration of the first biological agent was 5.76years. Most patients were treated with antiTNF as first line (90.3%):etanercept 69.2%,adalimumab 12.8%,infliximab 8.4%. Mean baseline active joint count was 5.1±5.8, decreasing to 1.2±2.4 and 1.0±3.1 after 6 months and 1 year of therapy. Mean ESR was 33.9±25.3 mm/1sth and 26.9±23.9 and 19.1±180 after 6 months and 1 year. CHAQ decreased from 0.8±0.7 to 0.4±0.5 and 0.4±0.5 at 6 months and 1 year. 14.1% switched once to other biological therapy (3.08% in the first 6 months,4.4% in the first year), 5.73% switched twice (0.88% in the first 6 months,1.76% in the first year) and 2 patients (0.88%) switched 3 times after the first year of treatment. 14 serious adverse events were reported leading to discontinuation of the treatment, 6 in the first 6 months and 8 in the first year of treatment. There were no reported deaths. The one-year treatment retention with biological agents was 91%. Conclusions JIA patients treated with biologics and registered in Reuma.pt showed a good profile of effectiveness and safety at 1 year. Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.3142

PReS-FINAL-2021: JADAS-CRP instead of JADAS-ESR...results from REUMA.PT

Recently, Juvenile Arthritis Disease Activity Score (JADAS) was found to be a valid instrument for assessment of disease activity. JADAS was developed with erythrocyte sedimentation rate (ESR) because C-reactive protein (CRP) values were not available in all databases used to validate the tool. Nordal et al compared recently in a Nordic population the JADAS based on CRP with JADAS based on ESR and concluded that these instruments correlated closely, indicating that both scores can be recommended for assessing disease activity in JIA.

Efeito do eptc + r 25788 em combinação com o diuron no controle de plantas daninhas e seletividade para a cultura da batata-doce

Four levels of EPTC + R 25788 (0.0; 1.6; 3.2 e 4.8 kg/ha) and diuron (0.0; 0.8; 1.2 and 1.6 kg/ha) with four replications were evaluated in a fatorial field experiment in a Utisol containg 3.5 % organic matter. Better control of nutsedge was obtained with the highest dosage of EPTC + R 25788, mainly in the absence of diuron. However, when the highest eradicane levels were applied as single treatments there was a marked increase in the broadleaf weed population. The best control of broadleaf weed population was achieved when the highest diuron levels were combined with the highest EPTC + R 25788 levels although this condition have not resulted in highest productions. The greatest sweet potato production was obtained with the combination of 6 1/ha of Eradicane plus 1.32 kg/ha of Karmex 800.