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LIXIVIAÇÃO DO SAFLUFENACIL EM SOLOS COM DIFERENTES TEORES DE MATÉRIA ORGÂNICA
No full textSaflufenacil is a herbicide recommended for use in the main agricultural crops in Brazil to control eudicotyledonous weeds. However, the application of saflufenacil has been carried out without previous knowledge of this herbicide interactions with soil colloids, which may increase environmental contamination risks. In this study, the leaching of saflufenacil in soil samples was estimated with different organic matter contents. Therefore, PVC columns were filled with samples of Xanthic Ferralsol (XF) and Ferralsol (F), with different physical and chemical attributes. Twelve hours after herbicide (70 g i.a. ha-1) application, the PVC columns were subjected to a rainfall of 60 mm. For the evaluation of saflufenacil leaching, the columns were sectioned in ten parts with 5-cm each. Saflufenacil leached up to 50 and 40 cm deep in the samples, with the lowest contents of organic matter of XF and F, respectively. The increase in organic matter content of Ferralsol and Xanthic Ferralsol samples reduced saflufenacil leaching and the symptoms of intoxication in the indicator species. There was an inverse relation between the content of organic matter and the leaching of the herbicide in both soils studied. It was observed that the application of saflufenacil in soils with low organic matter contents may represent a significant environmental contamination risk of soils and watercourses. Saflufenacil é um herbicida recomendado para uso nas principais culturas agrícolas no Brasil para o controle de plantas daninhas eudicotiledôneas. No entanto, o saflufenacil tem sido aplicado sem o conhecimento prévio desse herbicida com os coloides do solo, o que pode aumentar o risco de contaminação ambiental. Por essa razão, o objetivo deste trabalho foi estimar a lixiviação do saflufenacil em amostras de solos com diferentes teores de matéria orgânica. Para isso, colunas de PVC foram preenchidas com amostras de Latossolo Amarelo e Latossolo Vermelho-Amarelo com diferentes atributos físicos e químicos. Após a aplicação do herbicida, as colunas de PVC foram submetidas à 60 mm de chuva simulada. Para a avaliação da lixiviação do saflufenacil, as colunas foram seccionadas a cada 5 cm. O saflufenacil lixiviou até a profundidade de 50 e 40 cm das amostras de solo com o menor teor de matéria orgânica, do Latossolo Amarelo e Latossolo Vermelho-Amarelo, respectivamente. O aumento do teor de matéria orgânica em amostras de ambos os solos reduziu a lixiviação do saflufenacil e os sintomas de intoxicação da espécie indicadora. Observa-se que houve uma relação inversa entre o teor de matéria orgânica e a lixiviação do herbicida em ambos os solos estudados. Conclui-se que a aplicação do saflufenacil em solos com baixo teor de matéria orgânica pode representar um significativo risco de contaminação ambiental de solos e cursos d’água
DESEMPENHO AGRONÔMICO DE TOMATE TIPO SALADA CONDUZIDO EM DIFERENTES SISTEMAS DE CONDUÇÃO E DOSES ADUBAÇÕES
No full textLooking to reduce the cost and maximize tomato productivity, this study aimed to evaluate fertilizer doses and conduction systems. For this, a field experiment was carried out in randomized blocks, in a simple factorial scheme, which consists in four fertilizer doses, (50, 100, 150 and 200% dose), and four conduction systems (with one or two plants per pit, and one or two stems per plant). Plants were spaced 0.44m and 1.5m between lines. Each plot consisted of 10 plants. The evaluated characteristics were fruit mass, number of fruits, total production per plant and pit, longitudinal and transversal dimension of the fruit. Under the experiment conditions, interactions were observed between fertilization and conduction only for the transversal and longitudinal diameter. The C4 conduction system showed superior results for the estimated yield when compared to the treatments containing only one plant per pit (C1 and C2). For the fertilizer doses, the observed yield was 142.68 t ha -1, in the 150% dose, and 114.84 t ha -1 for the 50% dose. The highest production per pit was obtained in the 150% fertilizer dose and the C4 conduction, but this treatment showed a lower average fruit mass. The treatment with two plants per pit and two stems provided lower fruit average mass than the treatments containing a single plant. The fertilization influenced only in the longitudinal diameter, and the largest diameter was observed in the recommended fertilization dose. Aiming at cost/efficiency relation, the 100% dose and the C3 were considered the best treatments.Visando a redução do custo de produção de tomate e a maximização da produtividade, esse trabalho teve como objetivo avaliar doses de adubação e sistemas de condução de tomate tipo mesa, na região do Distrito Federal. Para isso foi desenvolvido um experimento em blocos ao acaso, em esquema fatorial simples, que consistia em 4 doses de adubação aplicada via fertirrigação (50, 100, 150 e 200% da dose recomendada) e 4 sistemas de condução (C1- Uma plant por cova com uma haste, C2- Uma planta por cova com duas hastes cada, C3- Duas plantas por cova com uma hase, C4- Duas plantas por cova com duas hastes cada). O espaçamento adotado foi de 0.44m entre plantas e 1.5 metros entre linhas. Cada parcela era composta por 14 plantas, das quais apenas 10 foram utilizadas na amostragem. Foram avaliadas as características de produtividade, massa de fruto, número de frutos por planta e cova, produção total por planta e cova, dimensão longitudinal e transversal do fruto. Nas condições do experimento, foram observadas interações significativas entre adubação e condução apenas para diâmetro transversal e longitudinal. Para todas as doses de adubação, o sistema de condução contendo duas plantas por cova com duas hastes apresentou resultado superior para a produtividade estimada quando comparados aos tratamentos contendo apenas uma planta por cova com uma haste, variando de 163.71 t ha -1, na dose de 150%, e 130.09 t ha -1 para a dose de 50%. A maior produção por cova foi obtida na condução com duas plantas com duas hastes, na dose de 150% de adubação, mas este tratamento apresentou menor massa média de frutos. O tratamento com duas plantas por cova com duas hastes proporcionou menor massa média de frutos do que os tratamentos contendo uma única planta para todas as doses de fertilizante, exceto na dose de 50%. A adubação influenciou apenas no diâmetro longitudinal, e o maior diâmetro foi obtido na adubação recomendada. Conduções com duas plantas por cova com duas hastes apresentaram diâmetros longitudinais menores em todas as adubações
EFICÁCIA DOS HERBICIDAS INDAZIFLAM E CLOMAZONE SOBRE PROBLEMÁTICAS PLANTAS DANINHAS DA FAMÍLIA POACEAE, PARA A CULTURA DA CANA-DE-AÇÚCAR
No full textIt is believed that indaziflam gives a longer period of weed control compared to clomazone, irrespective of the type or texture of the soil. Thus, the aim of this study was to evaluate pre-emergent control in five problematic weed species of family Poaceae to sugarcane, using the herbicides indaziflam and clomazone in two soils of different textures. Two experiments were carried out, one in a soil of a sandy-loam texture and the other in a clayey soil. For both experiments, a randomised block design of split plots was chosen, with four replications. The treatments consisted of the herbicides indaziflam (75 and 100 g ai ha-1), clomazone (1080 g ai ha-1) and a control with no herbicide. In the subplots, the treatments were Digitaria horizontalis, Panicum maximum, Rottboellia cochinchinensis, Urochloa decumbens and Urochloa plantaginea. Both herbicides were more effective in the clayey soil, but with indaziflam (100 g ai ha-1), more than 90% control of the weeds remained after 240 days after application (DAA), whereas for clomazone, control remained only up to 90 DAA. The herbicide clomazone did not satisfactorily control the weeds in the sandy-loam soil. The herbicide indaziflam did not control U. decumbens in the sandy-loam soil. D. horizontalis and R. cochinchinensis were the most sensitive species to the herbicide indaziflam, irrespective of soil texture.Acredita-se que o indaziflam proporcione um período mais longo de controle de plantas daninhas em comparação com o clomazone, independentemente do tipo ou textura do solo. Assim, objetivou-se com este trabalho avaliar o controle em pré-emergência de cinco espécies de plantas daninhas da família Poaceae, problemáticas para de cana-de-açúcar, com os herbicidas indaziflam e clomazone em dois solos de texturas distintas. Foram realizados dois experimentos, um em solo de textura franco-arenosa e outro em textura argilosa. Para ambos os experimentos, o delineamento escolhido foi o de blocos ao acaso, em esquema de parcelas subdivididas, com quatro repetições. Os tratamentos foram compostos pelos herbicidas indaziflam (75 g ia ha-1 e 100 g ia ha-1), clomazone (1080 g ia ha-1) e uma testemunha sem aplicação. Nas subparcelas os tratamentos foram as espécies, Digitaria horizontalis, Panicum maximum, Rottboellia cochinchinensis, Urochloa decumbens e Urochloa plantaginea. Os dois herbicidas foram mais eficazes em solo de textura argilosa, mas com indaziflam (100 g ia ha-1) o controle acima de 90% das plantas daninhas permanece até 240 DAA, enquanto com clomazone apenas aos 90 DAA. O herbicida clomazone não controlou satisfatoriamente as plantas daninhas no solo de textura franco-arenosa. O herbicida indaziflam não controlou a espécie U. decumbens em solo de textura franco-arenosa. D. horizontalis e R. cochinchinensis foram às espécies mais sensíveis ao herbicida indaziflam, independentemente da textura do solo
Correlation of biometric characteristics of fruits and seeds with the vigor of Agonandra brasiliensis seedlings in northern Amazonia
Get PDFThe goal of this study was to determine and correlate the main morphometric characteristics of fruits, seeds, and seedling vigor of Agonandra brasiliensis, in Roraima. The design was completely randomized with three treatments, consisting of six replications with 20 seeds. The treatments established were three classes of seeds: T1 - small seeds (S = 1.50-1.69 g); T2 - medium seeds (M = 1.70-1.89 g) and T3 - large seeds (L = 1.90-2.09 g). The variables evaluated were: length; diameter; the fresh mass of fruits and seeds; percentage, speed (in index) and average time of emergence, length of roots and aerial part; number of leaves; fresh, dry and total seedling mass; seedling lignification index; root/shoot ratio and dry root/shoot ratio and correlations between all studied variables. The fresh mass of the fruit of Agonandra brasiliensis has a high positive correlation with the mass of seeds. Small seeds of Agonandra brasiliensis exhibit a higher percentage of emergence in the conditions of the northern Amazon.Objetivou-se determinar e correlacionar as principais características morfométricas de frutos, sementes e o vigor de plântulas de Agonandra brasiliensis, em Roraima. O delineamento foi o inteiramente casualizado com três tratamentos, composto de seis repetições com 20 sementes. Os tratamentos estabelecidos foram três classes de sementes: T1 - sementes pequenas (P= 1,50-1,69 g); T2 - sementes médias (M= 1,70-1,89 g) e T3 - sementes grandes (G= 1,90-2,09 g). As variáveis avaliadas foram: comprimento; diâmetro; massa fresca dos frutos e de sementes; porcentagem, velocidade (em índice) e tempo médio de emergência, comprimento de raízes e parte aérea; número de folhas; massa fresca, seca e total das plântulas; índice lignificação de plântulas; relações raiz /parte aérea e massa seca de raiz /parte aérea e correlações entre todas as variáveis estudadas. A massa fresca do fruto de Agonandra brasiliensis apresenta correlação positiva alta com a massa de sementes. Sementes pequenas de Agonandra brasiliensis exibem maior percentagem de emergência nas condições da Amazônia setentrional
Organic onion growth, yield and storage improved by foliar sprays of microalgae and fulvic acid as a natural biofertilizer
Get PDFThe use of microalgae as natural biofertilizer in horticulture has recently been reported, while the use of humic substances is widespread. However, the combined use of microalgae with humic substances applied to plant leaves is still unexploited. Thus, the objective of this work was to combine fulvic acid (FA) with the Scenedesmus subspicatus microalga biomass (SC) as a natural biofertilizer applied via leaf in two onion cultivars in organic system. Four experiments were conducted: i) bioassays to verify the bioactive effect of FA, SC and combinations using the Vigna radiata model plant; ii) greenhouse pot experiment with foliar applications of FA, SC and combination in two onion cultivars; iii) field experiment in organic system with foliar applications of FA, SC and combination in two onion cultivars; and iv) onion bulb storage experiment. The bioactive effect of SC, FA and their combinations was identified by promoting changes in root growth of V. radiata. In pots, treatments containing FA, SC and combination promoted increase in fresh and dry leaf mass. The foliar application of FA, SC and combination promoted an increase in field bulb productivity, reduced mass loss in stored bulbs and increased carbohydrate, amino acid and protein contents in onion bulbs
LÂMINAS DE ÁGUA E ADUBAÇÃO NITROGENADA NO CRESCIMENTO E ACÚMULO DE BIOMASSA SECA DA CANA-DE-AÇÚCAR
No full textIrrigation and soil fertilization management are essential agricultural practices that improve the growth and development of sugarcane plants and, consequently, increase their production capacity, which is important for sugar and alcohol productions. In this context, the objective of this work was to evaluate the effect of water depths and nitrogen rates on the growth and dry biomass accumulation of sugarcane plants. The treatments consisted in four water depths (1,498; 1,614; 1,739; and 1,854 mm), five nitrogen rates (0; 20; 40; 80; and 120 kg ha-1) and five evaluation times. The experiment was conducted in a randomized block design with a split-split-plot arrangement and four replications, including the factors water depths, nitrogen rates, and days after planting. The dry biomasses of the plant pointer, leaves and culms, culm diameter, plant height, and number of plants were analyzed. The application of nitrogen increased the sugarcane biomass, mainly the pointer (with leaves) and dry culm biomass, and the number of plants. The highest dry culm biomass accumulation and dry leaf biomass were found at the end of the crop cycle for the treatment with the application of nitrogen rates of 80 and 120 kg ha-1. The increases in water depths applied increased the number of plants per linear meter, but the culm and dry leaf biomass did not happen.O manejo da irrigação e da adubação são práticas agrícolas fundamentais para melhoria do crescimento e do desenvolvimento das plantas e, consequentemente, do aumento da sua capacidade produtiva, que é importante para produção do açúcar e do álcool. Diante disto, objetivou-se com o presente estudo, avaliar o efeito de lâminas de água e doses de nitrogênio sobre o crescimento e acúmulo de biomassa seca da cana-de-açúcar (cana-planta). Os tratamentos consistiram em quatro lâminas de água (1498; 1614; 1739 e 1854 mm), cinco doses de nitrogênio (0; 20; 40; 80 e 120 kg ha-1) e cinco épocas de avaliação, arranjados em faixas e delineados em blocos ao acaso com quatro repetições. As variáveis analisadas foram a biomassa seca de ponteiros, folhas e colmos, o diâmetro de colmos, a altura e o número de plantas. A altura de planta foi favorecida tanto pelas lâminas de irrigação quanto pelas doses de nitrogênio. O nitrogênio promoveu aumento de biomassa na cana-de-açúcar, principalmente a biomassa seca do ponteiro mais as folhas e do caule e o número de plantas. O maior acúmulo de biomassa seca no colmo foi obtido no final do ciclo da cultura com a aplicação das doses de nitrogênio de 80 e de 120 kg ha-1. O aumento das lâminas de água aplicadas promoveu incrementos no número de plantas por metro linear, com a obtenção dos maiores números de plantas no início do ciclo da cultura
Effect of oral health intervention program on the self oral care of children attending childcare facilities: a quasi-experimental study
Get PDFThis study aimed to conduct a quasi-experimental study for assessing the effects of an oral health intervention program (OHIP), on the self-management of oral health in children attending childcare centers. The participants recruited were 83 children from two childcare centers, who were allocated to the intervention and control groups. The intervention group received the OHIP. At baseline, a self-reported survey of parents was conducted. In addition, the oral status of the children at baseline and at 5 weeks was evaluated. Their brushing behavior was assessed once a week and every day during the OHIP intervention period and at home, respectively. After the follow-up at 12 weeks, dental plaque index (PI) was measured and two-way repeated measures analysis of variance was performed. The PI of the intervention group significantly decreased at week 5, compared to the baseline (1.90 ± 0.53, p < 0.001). Despite a substantial increase in week 12 (2.67 ± 0.08, p < 0.001), the PI was significantly lower than that of the control group (3.37 ± 0.60). The OHIP was effective in reducing the PI and modifying the brushing behavior among children. It is necessary to develop and expand a systematic oral health education program to promote self-management of oral health in children
Biocontrol potential of Beauveria bassiana and Metarhizium anisopliae isolates from Turkey against Hyphantria cunea (Drury) (Lepidoptera: arctiidae) Larvae under laboratory and field conditions
Get PDFHyphantria cunea is one of the most important pest insects causing significant damage in many plant species. The present study aimed to evaluate the insecticidal activity of Turkey isolates of Beauveria bassiana and Metarhizium anisopliae against H. cunea larvae under laboratory and field conditions. B. bassiana isolates YK16, YK23 and YK26, and M. anisopliae isolates YK41 and YK45 were sprayed onto the larvae of H. cunea at the respective doses of 1x105 and 1x106 conidia mL-1 and monitored for seven days. Fungal isolates, bio-insecticide Bacillus thuringiensis and chemical insecticide diflubenzuron were used in field studies. Trials were carried out in five replications. All B. bassiana isolates caused 100% mortality on first instar larvae in laboratory trials. Mortality ratios ranged from 100 to 96% on second instar larvae. M. anisopliae isolates YK45 and YK41 caused 88 and 84%, and 81.33 and 77.11% mortalities for the first and second instar larvae, respectively. The mortality rates fluctuated between 91.78-72.89% for B. bassiana on third instar larvae in laboratory conditions. However, M. anisopliae isolates YK45 and YK41 caused 77.11 and 60.22% mortality on third instar larvae, respectively. In the field trials, B. bassiana YK23 displayed promising insecticidal activity with 80.60% mortality on second instar larvae of H. cunea. Other isolates as well caused mortalities ranging from 60.77 to 49.55%. The results revealed that some isolates of B. bassiana and M. anisopliae have potential to control H. cunea larvae. However, additional detailed studies need to be carried out to increase their effectiveness in field conditions
Quality of life and adherence to dental treatment in adolescents: a longitudinal analytical study
Get PDFThe study aimed to analyze the quality of life, oral health impact on daily activities and its association with adherence to dental treatment, and other factors, among vulnerable adolescents. It is a longitudinal analytical study performed with 15- to 19-year-old adolescents in the city of Piracicaba, São Paulo, from 2014 to 2015. The sample consisted of 476 adolescents referred for the treatment of caries and/or periodontal disease in family health units (initial phase). After 18 months, 325 individuals were assessed to investigate the dental treatment provided (final phase). The response variables considered in the final phase were the Quality of Life (WHOQOL-bref) and the Oral Impacts on Daily Performances (OIDP) questionnaires. The independent variables analyzed were sex, age, treatment adherence, and family cohesion and adaptability. A multiple regression model was used. The data on the physical (p<0.0001), social (p=0.0003), environmental (p<0.0001), and psychological (p<0.0001) domains of the WHOQOL collected in the initial phase had a positive relationship with the same domains assessed in the final phase. The WHOQOL data of the initial phase were associated with the WHOQOL data of the final phase (p=0.0341). The OIDP data of the initial phase were associated with the OIDP data of the final phase (p<0.0001). The OIDP of volunteers who did not adhere to dental treatment showed a higher impact (p=0.0234). The quality of life and impacts on daily performances of adolescents improved between the evaluation periods
AVALIAÇÃO DO METABOLISMO DE NITROGÊNIO E CARBONO EM PLANTAS DE PARICÁ - SUJEITAS A DIFERENTES CONCENTRAÇÕES DE CÁDIO
No full textThe development of anthropogenic activities such as industry, mining, agriculture, urban waste discard has been, the main actions that result in increased contamination by heavy metals in soil, water and air. One of the most harmful metals made available by these activities is cadmium, and even at low concentrations it is very toxic mainly in plant structures. The objective of this work was to verify the biochemical behavior of nitrogen and carbon metabolism in young plants of paricá when submitted to increasing cadmium application. For this, a completely randomized experiment was carried out with five treatments (control, CdCl2 178 μM, CdCl2 356 μM, CdCl2 534 μM, CdCl2 712 μM), with seven replicates, totaling 35 experimental units. The sensitivity of this vegetable to the increasing concentrations of cadmium was evident. The root system it presents’’ saw where the most toxic element accumulated, solutes such as carbohydrates, sucrose were affected in their concentrations, mainly in the leaves. The root system saw in its concentrations of glycine betaine a possibility of osmoprotection, but this did not reflect an increase in the concentration of nitrate in both leaf and roots. In the other hand, this fact not observed by the concentration of ammonium that increased in the root system. The results showed that the cadmium was transported to aerial part, however, concentrated mainly in the root system characterizing as a phytoextractor species.O desenvolvimento de atividades antrópicas como a indústria, mineração, agricultura, descarte de lixo urbano tem sido, as principais ações que resultam no aumento da contaminação por metais pesados no solo, água e ar. Um dos metais mais nocivos disponibilizados por essas atividades é o cádmio, e mesmo em baixas concentrações é muito tóxico principalmente nas estruturas das plantas. O objetivo deste trabalho foi verificar o comportamento bioquímico do metabolismo do nitrogênio e do carbono em mudas de paricá quando submetidas à aplicação crescente de cádmio. Para isso, foi realizado um experimento inteiramente casualizado com cinco tratamentos (controle, CdCl2 178μM, CdCl2 356μM, CdCl2 534μM, CdCl2 712μM), com sete repetições, totalizando 35 unidades experimentais. A sensibilidade deste vegetal às concentrações crescentes de cádmio é evidente. O sistema radicular foi onde o elemento tóxico se acumulou mais, solutos como carboidratos, sacarose foram afetados em suas concentrações, principalmente nas folhas. O sistema radicular viu em suas concentrações de glicina betaína uma possibilidade de osmoproteção, mas isso não refletiu um aumento na concentração de nitrato tanto na folha como nas raízes. fato não observado pela concentração de amônio que aumentou no sistema radicular. Os resultados mostraram que o cádmio foi transportado para a parte aérea, porém, concentrou-se principalmente no sistema radicular caracterizando-se como uma espécie fitoextratora