Resumo. O conteúdo de genética tem enfrentado uma série de dificuldades em ser compreendido pelos alunos em várias escolas desse país. Muitas delas são atribuídas a deficiências em conhecimentos pré-vios da área da Biologia Molecular, Citologia e, principalmente, ao raciocínio matemático. Além disso, as ferramentas metodológicas, empregadas por muitos dos professores, não têm contribuído para uma aprendizagem significativa do tema. Dessa forma, o presente trabalho buscou identificar as percepções e principais metodologias empregadas pelos professores da disciplina de Biologia no conteúdo de genética das escolas estaduais, localizadas no município de Jaguaribe-CE, analisando a percepção desses profissionais e dos alunos acerca do ensino -aprendizagem do conteúdo ministrado nas aulas. A pesquisa bibliográfica e de campo foi realizada nos meses de Junho e Julho de 2015. Além disso, foram aplicados questionários semiestruturados em um total de 06 professores e 54 alunos, versando sobre as metodologias empregadas no ensino de Genética, bem como a percepção deles em relação à influência dos procedimentos metodológicos na aprendizagem do conteúdo. Diante dos resultados encontrados na pesquisa, foi possível perceber que o ensino de genética nas escolas estaduais de Jaguaribe ainda está voltado, principalmente, para modelos tradicionais, com a prevalência de métodos expositivos de explicação do conteúdo. De maneira adicional, percebeu-se que os alunos possuem dificuldade em compreender o conteúdo de genética, devido a déficits de formação de base em outras disciplinas, principalmente a Matemática, que é bastante utilizada dentro dos cruzamentos e nos cálculos de probabilidade.Palavras-chaves: Ensino Médio. Ensino de Genética. Metodologias.Abstract. The genetic content has faced a number of difficulties in being understood by students in various schools of the country. Many of them are attributed to deficiencies in prior knowledge of the area of Molecular Biology, Cytology and mainly to mathematical reasoning. Moreover, the methodological tools employed by many of the teachers have not contributed to a significant learning theme. Thus, this study sought to identify main perceptions and methods used by the Biology discipline teacher in content genetics of state schools located in the city of Jaguaribe-CE, analyzing the perception of these professionals and students about the teaching -learning of the content taught in class. The literature and field research was conducted in June and July 2015. In addition, semi-structured questionnaires for a total of 06 teachers and 54 students were applied, dealing with the methodologies employed in genetics education, as well as their perception regarding the influence of methodological procedures in content learning. Given the results found in the survey, it was revealed that the genetic teaching in state schools of Jaguaribe is still geared primarily to traditional models, with the prevalence of expository methods of content explanation. Additional way, it was noticed that students h...

Crescimento foliar e atividades das enzimas antioxidativas em plântulas de girassol suplementadas com percolado de aterro sanitário e submetidas a estresse hídrico RESUMOEm regiões áridas ou semiáridas, a escassez hídrica tem sido um dos principais fatores limitantes da produção agrícola. Diante disso, o presente trabalho objetivou analisar os efeitos da aplicação de percolado de aterro sanitário no crescimento foliar (número de folhas e área foliar) e as atividades das enzimas antioxidativas: superóxido dismutase (SOD), catalase (CAT), peroxidase do ascorbato (APX) e peroxidase do guaiacol (GPX) em folhas e raízes de plântulas de girassol submetidas às condições de estresse hídrico. O delineamento experimental foi o inteiramente casualizado, disposto em arranjo fatorial dois (irrigadas ou não irrigadas) x quatro (areia; areia + adubo orgânico 100 kg N ha -1 ; areia + percolado de aterro sanitário 100 kg N ha -1 ; areia + percolado de aterro sanitário 150 kg N ha -1 ), com cinco repetições. Em relação aos parâmetros foliares, o tratamento 100 kg N ha -1 suplementado com percolado de aterro sanitário obteve os melhores incrementos no número de folhas e área foliar. Além disso, verificaram-se aumentos nas atividades das enzimas antioxidativas em folhas e raízes de plântulas de girassol suplementadas com percolado de aterro sanitário, sendo provável que as reduções dos efeitos deletérios do estresse hídrico nas variáveis foliares dos tratamentos suplementados com percolado de aterro sanitário tenham ocorrido em virtude das maiores atividades das enzimas antioxidativas, especialmente as da CAT nas folhas e GPX nas raízes. Rev. Ambient. Água vol. 12 n.

Many Brazilian reservoirs are intensely submitted to the silting process, particularly the small and medium size ones. The study aimed to examine the feasibility of using silt sediment to grow sunflower plants under conditions of water stress, by evaluating its effects on the relative chlorophyll contents, dry matter and antioxidative enzyme system. The study was conducted under greenhouse conditions at the Instituto Federal do Ceará Campus Maracanaú, Brazil. The sunflower seeds were sown in buckets containing 1) sand; 2) sand + manure/mixed organic fertilizer; 3) sand + 91.8 g of sediment, and 4) sand + 183.6 g of sediment. The sediment was collected from the Tijuquinha reservoir, Northeast of Brazil. The plants were watered daily to 70% field capacity. At 16 days after sowing, irrigation to half of each group of seedlings was suspended. The experimental design was completely randomized in a 2 × 4 factorial with five replicates. The data of each harvest time were analysed by analysis of variance and the means were compared by Tukey's test (P ≤ 0.05). The addition of silt sediment improved the variables (relative chlorophyll content, and shoot and total dry matters) compared to plants grown in substrate containing sand and sand + compost/mixed organic fertilizer, respectively. In general, a greater increase in the variables was observed with the 200% nitrogen recommendation treatment than the other treatments studied. It is possible that the silt sediment from reservoirs can be an alternative to chemical fertilizers for plant cultivation, reducing production costs, providing improvements in the quality of potable water and restoring the storage capacity of surface reservoirs lost by siltation.

Sanitary landfill leachate is one of the major problems arising from disposal of urban waste. Sanitary landfill leachate may, however, have use in agriculture. This study, therefore, aimed to analyze initial plant growth and gas exchange in sunflower seedlings supplemented with sanitary landfill leachate and subjected to drought stress through variables of root fresh mass (RFM), shoot fresh mass (SFM), total fresh mass (TFM), relative chlorophyll content (CL), stomatal conductance (g ), transpiration rate (E), net photosynthetic rate (A), ratio of internal to external CO concentration (Ci/Ca),water use efficiency (EUA), instantaneous carboxylation efficiency (A/Ci), and electron transport rate (ETR). The experimental design was a completely randomized 2 (irrigated and non-irrigated) × 4 (sand, sand + 100 kg N ha organic fertilizer, sand + 100 kg N ha sanitary landfill leachate, and sand + 150 kg N ha sanitary landfill leachate) factorial with five replicates. Under drought stress conditions, leachate treatment supplemented with 100 kg N ha exhibited higher plant fresh weights than those of the treatment containing 150 kg N ha. Increases in fresh mass in plant treatments supplemented with 100 and 150 kg N ha sanitary landfill leachate were related to higher photosynthetic rates.

Biodigesters have been used to convert biomass into biogas and biofertilizers. This energy use has been important for the reduction of solid waste pollution in the environment. This work aims to analyse the viability of the use of pig biofertilizer produced by an Indian biodigester prototype, monitored by a data acquisition system. The biodigester used was an Indian prototype built on a low cost material that is easy to acquire (polyvinyl chloride-PVC). After the biofertilizer production, we tested its efficiency and viability under conditions of vegetation house in the cultivation of sunflower plants. The experimental design was completely randomized in a factorial arrangement with 4 concentrations of biofertilizer (0, 40, 80 and 120 kg N ha -1 ) × 4 harvest periods (14, 21, 25 and 29 days after sowing). We evaluated biometric and vigor parameters by measurements of stem diameter, height of the aerial part, number of leaves and production of fresh and dry matter of roots, aerial and total parts, as well as the relative chlorophyll content. We performed the experiment with five repetitions using two plants each and we submitted the data to analysis of variance (ANOVA) and polynomial regression using the statistical software Sisvar 5.4. The functional Indian biodigester prototype produced a biofertilizer of excellent quality and viability as a biofertilizer for the initial growth of sunflower plants. The biofertilizer served as a nutritional source in the sunflower crop, since it provided increases in all the growth parameters analyzed in relation to the control group (plants in the absence of biofertilizer), especially in the concentration of 120 kg N ha -1 .