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The Visual Evaluation of Soil Structure (VESS) is a straightforward and practical method for characterising and scoring soil structural and physical quality, ideally suited to evaluate and monitor soil degradation in remote and undeveloped areas. The research presented here tested for the first time the feasibility of using VESS in the Amazon basin, under the specific land uses and soils (Oxisol and “Terra Preta de Indio”) of the region, and its relation with quantitative soil properties commonly used as indicators of soil physical quality. The evaluated areas, which had never been subjected to mechanisation, chemical fertilisation nor tillage, were “Terra Preta de Indio”/Anthropogenic Dark Earth; Regenerating Forest; Slash and Burn; Pasture; and Pristine Forest. The results showed that the quantitative properties were less sensitive at revealing signs of degradation than VESS and that VESS brought to light evidence of historic land use change and limitations to crop productivity. VESS was significantly correlated with soil resistance to penetration. However, VESS had difficulty capturing surface sealing, but the hands on approach to VESS allowed the user to identify these problems, despite not being listed in the reference chart. Overall, VESS was a more integrated soil quality indicator, providing more information about different soil functions than the quantitative properties, it was also a more practical method to perform making it ideal for tracking soil degradation and structural quality in similarly challenging situations. However, more research is required to fully enable VESS to capture structural quality in ‘sandified’ soils, caused by the slash and burn method widely used in the Amazon region.

Camu-camu is an Amazonian fruit that has high levels of vitamin C, however, there is a need to expand knowledge to carry out systematic and consistent studies in the various fields of knowledge, and those related to mineral nutrition. The objective of this work was to evaluate the nutritional and growth status of camu-camu by the missing element technique and the use of liming, using as substratum a dystrophic Yellow Latosol of central Amazonian texture. The experimental design was a randomized block design with four replications and 15 treatments: complete, liming omission, individual omission of N, P, K, Ca, Mg, S, Zn, Mn, Cu, B, Cl and Mo. of the witness (natural soil). The characteristics evaluated were: height, neck diameter, leaf, stem, shoot, root and total dry matter, relative growth, shoot and root ratio, and nutrient accumulation of shoot (leaf) dry matter. All data evaluated were statistically significant. Liming and fertilization were necessary for acidic and low natural soils when comparing the complete with the control. Ca and P were the most limiting nutrients, while omission of N reduced the growth of seedlings. Based on total dry matter, the nutritional requirement of camu-camu was in decreasing order: Ca > P > S > Cl > Cu > Mg > Z > K > Mo > Mn > B > N.

Amazonian soils have some physical, chemical and mineralogical differences, understanding the differences is important to understand the behavior of nutrients in the soil, especially phosphorus. The study was carried out in two types of soils: a Hydromorphic soil profile and a Non-hydromorphic soil profile in the Central Amazon region of Brazil, located in the metropolitan area of Manaus. Five depths were sampled: 0.00-0.05; 0.05-0.1; 0.1-0.2; 0.2-0.4; and 0.4-0.6 m. Physical, chemical, mineralogical and morphological attributes of both soils were studied. With the exception of clay, the levels of sand and silt remained stable in depth. The levels of organic matter gradually decrease in depth. The pH in water and in KCl, ∆pH, point of zero load, were similar between the surface and subsurface soils. Al3+, H++Al3+, CECt, CECT and clay activity were similar in Non-hydromorphic soil and increase in surface (< 0.2 m) and stabilize in subsurface (> 0.2 m). In both soils, the bases are reduced in subsurface (> 0.2 m). Aluminum and iron oxalate reduce with greater expressiveness in Non-hydromorphic soil. Aluminum and dithionite iron exhibit the same behavior. The levels of Goethite (Gt) and Hematite (Hm) are high in depth in the Non-hydromorphic soil and decrease in the Hydromorphic soil. There are sensitive distinctions between soils, due to the imposed edaphoclimatic conditions.

With the growing global energy demand, greater attention has been focused on the production of oilseeds as alternative energy sources, which will necessitate increased production and, correspondingly, increased irrigation. The aim of this work was to study the effect of different soil water tensions on drip-irrigated castor beans (cv Al Guarany 2002). The experiment was conducted in Lavras, Minas Gerais State, Brazil (21°14′ S, 45°00′ W, altitude, 918.8 m) during the period from 1/24/2008 to 8/30/2008. The experiment used a randomized block design with four replications and five treatments, exposing the crop to soil water tensions of 15, 30, 45, 60 and 75 kPa beyond the tension found with no irrigation (Ni), at a depth of 0.20 m. The variables analyzed were as follows: fruit mass of the primary (MPR), secondary (MSR) and tertiary (MTR) racemes; their grain yields (YPR, YSR and YTR, respectively); the total yield (YTC); the 100-seed weight (W100S); and the fruit seed conversion factor (FSF). It was observed that fruit mass and grain yield (MPR, MSR, and MTR and YPR, YSR, YTR, and YTC) decreased linearly with increasing water restriction for all racemes, with soil moisture near field capacity showing the highest values (185, 122, and 39 g raceme −1 and 678, 891, 425, and 1994 kg ha −1 , respectively). In the control treatment (Ni), MPR (86 g raceme −1 ) was similar to MPR at 60 and 75 kPa, and YPR (316 kg ha −1 ) corresponded to 80% of YTC. In soil water tensions up to 45 kPa, MPR was the most sensitive to water deficit, followed by MSR and MTR, although this pattern inverted at higher tensions.

This experiment was conducted in Lavras - state of Minas Gerais (MG), Brazil, in a protected environment, and aims to estimate the irrigation depths that maximize productivity and economic returns in the cultivation of asparagus bean and analyze the economic viability of irrigation management. The experimental delineation was randomized blocks with five treatments and four replications. The treatments consisted of five drip irrigation depths: 40, 70, 100, 130 and 160% of water replacement depth up to field capacity. The depths of water that maximize productivity and economic returns were obtained from the regression model adjusted to productivity data, cost of product relations and water cost. The economic viability was achieved on the benefit/cost ratio basis. The depth with the maximum economic return was estimated in 434.4mm, with a productivity of 35,160.6kg ha-1, which is economically viable for the cultivation of asparagus bean, with a expected profitability of R$ 1.70 for every real invested. O experimento foi conduzido em Lavras-MG, e teve como objetivo avaliar, técnica e economicamente, o efeito de diferentes lâminas de irrigação aplicadas por gotejamento na produtividade do feijão-de-metro. O delineamento experimental foi em blocos casualizados, com cinco tratamentos e quatro repetições. Os tratamentos constituíram-se de cinco lâminas de irrigação por gotejamento, sendo: 40; 70; 100; 130 e 160 % da lâmina de reposição de água até a capacidade de campo. As lâminas de água que maximizam a produtividade e o retorno econômico foram obtidas a partir do modelo de regressão em função de dados de produtividade, das relações de preço do produto e do custo da água. A viabilidade econômica foi obtida com base na relação benefício/custo. A lâmina de máximo retorno econômico foi estimada em 431,3 mm, com uma produtividade de 35.156,6 kg ha-1, que é viável economicamente para o cultivo do feijão-de-metro, com uma rentabilidade esperada de R$ 1,7 para cada real investido.

RESUMO Objetivou-se, com este estudo, avaliar o efeito de diferentes tensões da água no solo sobre a produção de duas cultivares de cenoura irrigadas por gotejamento. O experimento foi conduzido em Lavras, Minas Gerais (21º 14' S, 45º 00' W e 918,8 m), no período de julho a outubro de 2010. O delineamento experimental utilizado foi em blocos casualizados, em esquema fatorial 2 x 6, com quatro repetições. Os tratamentos se constituíram de duas cultivares de cenoura, cultivar não híbrida Nantes e cultivar hibrida Nayarit F1, além de seis níveis críticos de tensão da água no solo, 15, 25, 35, 45, 60 e 75 kPa. Com os resultados concluiu-se que o híbrido Nayarit F1 apresentou melhores respostas com relação às seguintes características analisadas: produtividade total de raízes, produtividade de raízes comerciais, massa média de raízes comerciais e eficiência no uso da água. Visando à obtenção de maiores produtividades de raízes (total e comercial) e maior massa média de raízes comerciais, em ambas as cultivares, deve-se irrigar no momento em que a tensão da água no solo estiver em torno de 15 kPa na profundidade de 0,15 m. O valor mínimo encontrado para a raízes do tipo refugo ocorreu na tensão de 21 kPa, resultando em um valor mínimo de massa raiz de 41,67g. ABSTRACT Different soil water tension values were tested to evaluate the effects on yield of two drip irrigated carrot cultivars. The experiment was carried out at Lavras, in the State of Minas Gerais, Brazil (21º 14' S, 45º 00' W and 918.8 m), from July to October 2008. The statistical design used was randomized blocks in a 2 x 6 factorial scheme with four replications. The treatments consisted of two cultivars of carrot (hibrid in Nayarit F1 and non hybrid Nantes) and six critical soil water tension levels (15, 25, 35, 45, 60 and 75 kPa). It can be concluded that the hybrid Nayarit F1 presented the best response in relation to the following analyzed variables: total root yield, marketable root yield, average marketable root mass and water use efficiency. In order to obtain larger root yield (total and marketable) and average marketable root mass, for both cultivars, the irrigation should be provided when soil water tension reaches 15 kPa at 0.15 m depth. The minimum value found for the roots of non comercial value occurred at a tension of 21 kPa, resulting in a low root mass of 41.67g.

Made available in DSpace on 2013-09-27T14:53:06Z (GMT). No. of bitstreams: 1 WOS000314514800018.pdf: 644840 bytes, checksum: 6966b577797b5abea7980ce37e92b2f0 (MD5) Previous issue date: 2012-01-01 Made available in DSpace on 2013-09-30T19:24:57Z (GMT). No. of bitstreams: 1 WOS000314514800018.pdf: 644840 bytes, checksum: 6966b577797b5abea7980ce37e92b2f0 (MD5) Previous issue date: 2012-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:34:53Z No. of bitstreams: 1 WOS000314514800018.pdf: 644840 bytes, checksum: 6966b577797b5abea7980ce37e92b2f0 (MD5) Made available in DSpace on 2014-05-20T15:34:53Z (GMT). No. of bitstreams: 1 WOS000314514800018.pdf: 644840 bytes, checksum: 6966b577797b5abea7980ce37e92b2f0 (MD5) Previous issue date: 2012-01-01 With the aim of minimizing the difficulties faced by the producers on cultivating the crisphead lettuce (Lactuta sativa L), specifically those related to the lack of technical information about the quantity of water to be applied, a study was made in order to determine the effect of various water depths on crisphead lettuce yielding characteristics. The experiment was carried out at the Universidade Federal de Lavras (UFLA), from October to December 2008 in greenhouse. A randomized block design with five treatments and four repetitions was applied. The treatments, consisting of the five respective evaporation factors; , 0.30 EVm; 0.60 EVm; 0.90 EVm; 1.20 EVm; 1.50 EVm (evaporate depth), were done according to an evaporated depth of a reduced pan. The results showed that: The maximum commercial yield, 36.5 t ha(-1), was estimated by applying a 164.8 mm depth, which corresponded to a water reposition factor of 98 %; the highest water usage efficiency (962.45 kg ha(-1) mm(-1)) was attained when an irrigation depth of 50.10 mm (30%) was used. Univ Fed Rural Amazonia, DCEE, Paragominas, PA, Brazil Universidade Federal de Lavras (UFLA), UFLA, Lavras, MG, Brazil Fundação Univ Fed Grande Dourados, Dourados, MS, Brazil Universidade Federal de Lavras (UFLA), Lavras, MG, Brazil Univ Estadual Paulista Julio de Mesquita Filho UN, São Paulo, Brazil Univ Estadual Paulista Julio de Mesquita Filho UN, São Paulo, Brazil

Objetivou-se, com o presente trabalho, uma avaliação técnica e econômica da produtividade do pepino japonês (Cucumis sativus L.) em função de diferentes lâminas de irrigação. O experimento foi instalado em casa de vegetação, utilizando-se de um delineamento inteiramente casualizado (DIC), com cinco tratamentos de reposição de água no solo (50, 75, 100, 125 e 150%) e seis repetições. Os resultados permitiram concluir que, de maneira geral, o número e o peso dos frutos da cultura foram afetados pelo déficit e excesso hídrico, aplicados pelos tratamentos. A máxima produtividade obtida foi igual a 45.944 kg ha-1 com aplicação de 320 mm e a lâmina ótima econômica foi estimada em 319,5 mm, concluindose que, para o pepino japonês, maiores retornos econômicos são obtidos mantendo-se a cultura com umidade do solo próxima da capacidade de campo, repondo integralmente a quantidade de água consumida. This study had the aim to verify the economic feasibility of japanese cucumber (Cucumis sativus L.) yield under different irrigation depths, cultivated in greenhouse. A completely randomized design (CRD), with five levels of replacement of irrigation water (50, 75, 100, 125 and 150%) and six replications was used. The results showed that the number and fruit weight of crop were affected by treatments of water deficit and excess used for treatments. The maximum productivity obtained was equal to 45,944 kg ha-1 for a depth of 320 mm and the economic optimum irrigation depth was estimated at 319.5 mm, concluding that for the japanese cucumber higher economic returns are obtained by keeping the crop with soil water content near field capacity, restoring the full amount of water consumed.

The experiment was performed in the experimental area of the Engineering Department Federal University of Lavras, Minas Gerais State, Brazil. It aimed at identifying the adequate irrigation management of the greenhouse-cultivated Japanese cucumber (Cucumis sativus L.). complete randomized design, with four levels of soil water potential (15; 30; 60 e 120 kPa) at two phenological phases (vegetative and reproductive), and 5 replications. Overall, the results showed decrease of yield according to increase of soil water potentials. During the reproductive stage, Japanese cucumber plants were more sensitive to water deficit, resulting in further decrease in yield compared to applied water deficit during the vegetative stage of the culture. O experimento foi realizado na área experimental do Departamento de Engenharia da Universidade Federal de Lavras, em Lavras - MG, e teve como objetivo identificar um manejo adequado da irrigação para a produção do pepino-japonês (Cucumis sativus L.) cultivado em ambiente protegido. Foi utilizado um delineamento inteiramente casualizado, envolvendo, como tratamentos, quatro níveis de potencial de água no solo (15; 30; 60 e 120 kPa) em duas fases fenológicas da cultura (vegetativa e reprodutiva), com 5 repetições. De forma geral, os resultados mostraram decréscimo da produtividade de acordo com o incremento do potencial de água no solo; as plantas do pepineiro-japonês, quando na fase reprodutiva, mostraram-se mais sensíveis ao déficit hídrico, redundando em maiores quedas de produtividade em comparação com o déficit hídrico aplicado durante a fase vegetativa da cultura.

O mogno (Swietenia macrophylla King), pelo elevado valor comercial da sua madeira, é uma das espécies mais exploradas na Amazônia, sendo ameaçada de extinção por não haver renovação dos estoques através de reflorestamento com a espécie. O objetivo deste trabalho foi avaliar o efeito da adubação fosfatada sobre o desenvolvimento de mudas de mogno. O estudo foi conduzidos em casa-de-vegetação e o solo utilizado para compor o substrato foi Latossolo Amarelo de textura muito argilosa. Os tratamentos constituiram-se de doses crescentes de fósforo de 0, 25, 30, 75, 100, 150 e 200 kg.ha-1 de P. O delineamento experimental foi o de blocos casualizados com 4 repetições, num total de 28 parcelas. Cada parcela foi formada por 2 mudas, cultivadas em sacos com capacidade de 4 dm³. Verificaram-se respostas positivas às doses de fósforo para todas as características de crescimento, bem como na absorção da maioria dos macronutrientes. Para as características de crescimento a dose de 200 kg.ha-1 de fósforo, foi a que proporcionou máximo crescimento para as mudas de mogno, no intervalo de 90 dias. ABSTRACT Due to the high value of mohogany woods (Swietenia macrophylla King), this specie is one of the most explored in the Amazon region. That explains the reason why mahogany is almost extinct.The present work evaluates the effect of phosphated fertilization on the mahogany seedlings under the increased doses of phosphorus. The experiment happened in a greenhouse and the soil used to compose the substratum was a yellow oxisoil with a very argillaceous texture. The treatments were made by doses of P: 0, 25, 30, 75, 100, 150 and 200 kg.ha-1 of P. The experimental design consisted of four randomized blocks, for a total of 28 parcels. Each parcel was formed by 2 seedlings, cultived in bags with 4 dm³ of soil. It was noticed positive answers by seedlings cultivated species for all the biometric characters analyzed and, in the same way, for the contents of almost the analyzed nutrients. For the growth characteristics, 200 kg.ha-1 was the dose that provided the high growth for mohogany, on the interval of 90 days.