Reguladores Vegetais E Sombreamento Na Emergência De Plântulas De Macadâmia

This study aimed to evaluate the effect of plant growth regulators and shading on seed germination of macadamia nut trees. The experiment was conducted in a seedling production nursery of the company "QueenNut Macadâmia" located in the "Palmeiras" Farm, Dois Córregos, São Paulo (SP) state, Brazil. The Treatments were T1: water (control) under a shading screen, T2: GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) at 200 mL L-1 under a shading screen, T3: Promalin® at 400 mL L-1 under a shading screen, T4: gibberellic acid (GA3) + kinetin (Kt) + 3- indolebutyric acid (IBA) - Stimulate® at 5 mL kg-1 seeds under a shading screen, T5: Stimulate® at 10 mL kg-1 of seeds under a shading screen, and T6: water (control) under no shading screen. Seeds were soaked in the solutions or in water containing plant growth regulators for 24 hours. Then, they were dried and sown in sand. 450 seeds were used for each treatment. The evaluations began from seedling emergence by counting the total number of seedlings per treatment. A high average of macadamia nut tree seedling emergence was obtained in the treatments GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) 400 mL L-1 with Sombrite® (75.7%), GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) 200 mL L-1 (72.6%) Sombrite® and water (control) without Sombrite® (71.5%). © 2016, Universidade Federal de Uberlandia. All rights reserved.3251263126

Sistema com aeração, decantação e filtragem para a melhoria da qualidade de água em irrigação localizada System with aeration, sedimentation and filtering for the improving of water quality in drip irrigation

A qualidade da água é muito importante para irrigação por gotejamento, pois ela escoa por pequenos bocais dos emissores, podendo ocorrer obstrução devido à deposição dos sólidos em suspensão. Portanto, antes da instalação do projeto, devem-se avaliar parâmetros de qualidade da água, para adotar medidas preventivas, evitando o risco de entupimento do sistema. Este trabalho teve como objetivo avaliar um sistema composto por aeradores com aspersores, sobre leito de pedra, para a precipitação dos íons Fe+2e Mn+2 em tanque de decantação, e um conjunto de filtragem composto por três filtros de areia e um de disco, em sistema de irrigação localizada. O trabalho foi realizado na Fazenda Alvorada, no município de Nova Granada - SP, no período de março a outubro de 2008. Foram realizadas determinações de variáveis físicas e químicas da água, ao longo do sistema de aeração, decantação e filtragem, o qual foi eficiente para a melhoria da qualidade de água, reduzindo os níveis de risco de entupimento de severo para médio e de médio para baixo. Oxigênio dissolvido, condutividade elétrica, pH, Fe+2e Fe+3 não diferenciaram a qualidade de água entre os pontos do sistema de tratamento, porém a turbidez, sólidos dissolvidos, sólidos em suspensão, ferro total e manganês total reduziram-se significativamente pelo uso do sistema proposto, melhorando a qualidade da água.<br>Water quality is very important to drip irrigation, as it flows in small diameter holes, and may cause obstruction due to deposition of solid matter. Whence the water must be evaluated before installation of the project. Parameters related to water quality are essential to define conducting measures to avoid the risk of clogging the system. This study aimed to evaluate a system with sprinklers aeration on bedrock, for Fe+2and Mn total precipitation in sedimentation tank and a set of filtering consisting of three sand filters and a disk, installed in drip irrigation system. The study was conducted at Alvorada Farm, in the municipality of Nova Granada - SP, Brazil, from March to October of 2008, when the physical and chemical water analyses were made. It was concluded that: the aeration system, sedimentation and filtration were efficient for improving water quality, reducing the levels of risk of severe to medium obstruction and medium to low obstruction. The variables, dissolved oxygen, electrical conductivity; pH, Fe+2and Fe+3 were not significant to indicate differences of water quality among the points of the water treatment. However, the variables such as: turbidity, dissolved solids, suspended solids, total iron and Mn+2 were statistically significant for the differentiation of the water quality

Contaminação por mercúrio em sedimento e em moluscos do Pantanal, Mato Grosso, Brasil Mercury contamination in sediment and in molluscs of Pantanal, Mato Grosso, Brazil

<abstract language="eng">The total level of mercury detected in the sediment and in the tissues of molluscs from the Bento Gomes basin, although low, have shown that the mercury used in the gold mining activities in the Poconé wetlands has contaminated those aquatic habitats in Pantanal. From 69 sediment samples analyzed, 26 % (N = 18) have shown levels ranging from 0.01 to 0.25µg.g-1 of mercury (moist weight). Mercury levels analyzed in 54 samples of mollusc tissues (Ampullaria scalaris Orbigny, 1835; A. canaliculata Lamarck, 1819 and Marisa planogyra Pilsbry, 1933) have shown that 30% (N = 16) were contaminated with levels ranging from 0.02 to 1.16µg.g-1 moist weight. This study shows that the mercury used in digs for gold mining and released into the environment has reached the habitats of Pantanal spread from the sediment into the molluscs living in the region