RESUMOO cedro-australiano (Toona ciliata M. Roem var. australis) é uma espécie promissora para plantios comerciais em função da qualidade e ampla utilização da sua madeira e de seu alto retorno financeiro em um pequeno espaço de tempo. No entanto, são escassas as informações sobre o comportamento desta espécie em relação à acidez do solo. Nesse sentido, objetivou-se avaliar a influência de diferentes níveis de saturação por bases sobre o crescimento e a qualidade de mudas de cedro-australiano. A saturação por bases do substrato foi elevada para 21,3; 33,2; 47,9; 60,4 e 70,0%, através da adição de diferentes doses de calcário com teor de 12% MgO e 50% CaO (PRNT 95%) em vasos com capacidade para 3,5 dm 3 que continham Latossolo Vermelho Distroférrico típico. Aos 120 dias após o transplantio foram obtidos: altura, diâmetro do coleto, matéria seca das raízes, parte aérea e total. Determinou-se, também, as relações altura/diâmetro do coleto, altura/matéria seca da parte aérea, matéria seca da parte aérea/matéria seca de raiz e o índice de qualidade de Dickson. As mudas de cedro-australiano respondem positivamente à elevação da saturação por bases. As respostas positivas das variáveis morfológicas analisadas apontam para a necessidade de se fazer a correção da acidez do solo elevando o nível de saturação por bases para 50%, no intuito de maximizar a produtividade da cultura. Palavras-chave: saturação por bases; cedro-australiano; qualidade de mudas. ABSTRACTThe Australian cedar (Toona ciliata M. Roem var. australis) is a promising species for commercial plantations based on the quality and wide use of its wood and high financial returns in short time. However, there is little information about the behavior of this species in relation to soil acidity. In this sense, the objective of this study was to evaluate the influence of different base saturation levels on growth and quality of Australian cedar seedlings. The substrate saturation was raised to 21.3; 33.2; 47.9; 60.4 and 70.0%, by adding different doses of limestone content of 12% MgO and 50% CaO in vessels with capacity of 3.5 dm 3 of a typical dystrophic Red Latosol (Oxisol). At 120 days after transplanting were obtained height, stem diameter, root dry matter, aerial parts and total. It was also determined the relationship height/stem diameter, height/aerial parts dry matter, aerial parts dry matter/root dry matter and Dickson's quality index. Australian cedar seedlings respond positively to the base saturation increase. The positive responses of morphological variables pointed to need to do the acidity correction increasing the level of saturation to 50 %, in order to maximize the crop yield.

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The excessive use of agrochemicals in agriculture has been causing irreversible environmental impacts, from this point of view, organic farming appears as an economically viable alternative to minimize these impacts. So, the objective of this work was to evaluate the effect of different types organic fertilizers in the development and production of coriander harvested at different epochs. The experiment was conducted during the period from August to October 2016, in an area of the experimental farm of University of International Integration of Afro-Brazilian Lusophony. The experimental design was a randomized complete block design, in a 5 × 4 factorial scheme, consisting of five organic fertilizers and four harvesting epochs (28, 35, 42 and 49 days after planting-DAP) and five blocks. The variables stem diameter, plant height, root size, number of leaves, leaf length and productivity were evaluated. All the analyzed variables responded significantly by the F test, either for the qualitative factor, fertilizer sources, or the quantitative, epochs of evaluation. Regarding the cultivation epochs, when the first evaluation period (28 DAP) was compared with the last (49 DAP), it was verified that the variables presented linear responses over time, with increases of 34.4% for height , 29.5% for stem diameter, 37.07% for root length and 64.44% for production. In relation to the fertilizer sources, in general, the cattle manure provided a greater growth and production of the coriander plants, being therefore the most suitable for the cultivation.

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Nitrogen fertilization is an important input for crop yield; however, it can result in detrimental environmental effects due to low use efficiency of regular N sources. This study evaluated the effects of N fertilizers and application strategies (single vs. split application) on bermudagrass (Cynodon spp.) responses and release pattern and rate in controlled and field incubations. The bermudagrass study was arranged in a two-way factorial scheme of 6 N fertilizers, urea, Polymer Coated Urea (PCU), PCU-6 (6 months), PCU-4 (4 months), PCU-2 (2 months) and urea + urease inhibitor (U-NBPT) applied as a single (400 kg N ha-1 yr-1) or two split applications of 200 kg N ha-1 (400 kg N ha-1 yr-1). The controlled experiment was a two-way factorial of PCU-6, PCU-4, PCU-2 and 15, 45 and 90% water hold capacity (WHC), sampling period of 170 days, the field incubation used the same sources sampled up to 220 days. Enhanced-efficiency fertilizers (EEF) increased herbage accumulation (HA) by 1.3 Mg ha-1 compared to untreated urea, on average. Nitrogen use efficiency (NUE) was greater for EEFs (44%) than urea (36%). Results showed that increased soil moisture inferred positive responses in release pattern and a minimum of 45% WHC was necessary for optimum release. Fertilizers at field conditions resulted in an earlier release than expected, ~20 days.