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RESUMO:Visando à otimização do uso da água na produção de alimentos, este artigo teve como objetivo avaliar o desempenho da TDR e de um acionador automático para irrigação na produção da alface em solos com diferentes doses de um polímero hidrofílico. Em casa de vegetação, foram realizados dois ensaios em vasos de 3 litros cultivados com alface. O primeiro foi realizado na primavera de 2011, utilizando 2 texturas de solo (arenosa e argilosa) e a presença/ausência do hidrogel. O segundo ensaio foi realizado no outono de 2012, utilizando 4 doses de hidrogel (0; 8; 16 e 24 g por vaso) no solo de textura arenosa. Aos 38 (2011) e 44 (2012) dias após o transplantio (DAT) das mudas, foram realizadas as colheitas e a avaliação das plantas cultivadas. O hidrogel não representou uma fonte de erros para o funcionamento da TDR, e o dispositivo acionador automático para irrigação respondeu adequadamente à presença do hidrogel nos solos com diferentes texturas. Em geral, foi verificada maior eficiência do uso da água nas plantas desenvolvidas na presença do hidrogel. As plantas cultivadas em solo com 16 g por vaso de hidrogel destacaram-se em massa seca e fresca da parte aérea. PALAVRAS-CHAVE: polímero hidrofílico, TDR, automação e gotejamento. LETTUCE GROWING UNDER AUTOMATED IRRIGATION AND HYDROGEL APPLICATIONABSTRACT: This paper aimed at evaluating the performance of a time domain reflectometry (TDR) and automation of an irrigation system to optimize water use in lettuce production in soils with different doses of hydrogel. For that, two greenhouse experiments were carried out with lettuce seedlings in 3-L pots. The first experiment was performed during the spring of 2011 using two soil textures (sandy and clayey) and presence or absence of hydrogel. The second one was made in the fall of 2012 using four doses of hydrogel (0, 8, 16 and 24 g per pot) in a sandy textured soil. The evaluations were carried out at 38 (2011) and 44 (2012) days after transplanting (DAT) of the seedlings. Results showed that hydrogel application did not affect the TDR performance. In addition, the automatic trigger device used for irrigation had adequate resposnses to hydrogel application in both soils. Overall, plants grew better in soils treated with hydrogel and the application of 16 g hydrogel per pot stood out since provided larger amounts of fresh and dry matter of plant shoot.

RESUMO O presen te estudo teve como objetivo comparar um sistema automático de baixo custo a outras duas técnicas de manejo (sistema Irrigás e tanque classe A) na cultura da alface (Lactuca sativa L.) com relação à operacionalidade dos sistemas, custo dos equipamentos, lâminas aplicadas e dados AAI/9kPa, Irrigás, AAI/12kPa foi, respectivamente, 241,4; 217,9; 205,5 AAI/9kPa, Irrigás, AAI/12kPa were, respectively, 241.4, 217.9, while the productivities were, respectively, 32.80, 28.86, 28.80 and 35.45Mg

The responses of oregano plants to water limitation from soil and seasonal phenological cycle are not fully understood yet. The aim of the present research was to help understanding the production of oregano essential oil and biomass facing soil water deficit, which was studied in different seasons. Oregano was subjected to drip irrigation, the water deficit being assessed in the vegetative and pre-flowering stages, as well as whole cycle analysis, through water matric potentials in the soil. The matric potential -60.8 kPa adopted in the irrigation handling during the oregano cultivation interval, led to higher essential oil content and yield. The same potential applied during the oregano pre-flowering stage resulted in the best mean of oregano fresh biomass production. The best dry biomass production was reached by using the matric potential -91.2 kPa in the oregano pre-flowering irrigation management. Water restriction in the soil throughout the entire phenological cycle favored essential oil production, whereas the water restriction during the pre-flowering stage enabled high oregano dry biomass production. The highest values for biomass and essential oil productions were reached for the oregano plants cultivated during spring/summer.

Baccharis trimera (Less.) DC (E1) and Baccharis crispa Spreng. (E2) possess potential antimicrobial and anti-inflammatory properties. Qualitative and quantitative information on seed germination on these species is scarce. The objective of this investigation was to establish a protocol for evaluating seed germination of E1 and E2 and to analice the scoring and curve fitting by the Germinator package, for different periods of germination were between 0.93 and 0.99. Both species showed differences in germinability and mean germination time, 27 days for E1 and 20 days for E2. The germination dispersion showed that E1 germination was homogeneous, with differences in growth pattern, whereas the results on germination of E2. The mean speed of germination determined with the experimental data was close to the values obtained by the Germinator package, with a maximum germination of more than 34%, proving that the software was efficient for evaluating germination.

PRODUÇÃO E TROCAS GASOSAS DO CAPIM-MOMBAÇA (Panicum maximum Jacq. cv. Mombaça) EM FUNÇÃO DE NÍVEIS DE DEPLEÇÃO DE ÁGUA NO SOLO  DIEGO BRANDÃO1*; SERGIO NASCIMENTO DUARTE2; JEFFERSON VIEIRA JOSÉ3; HUGO THANER DOS SANTOS4 E PEDRO RAMUALYSON FERNANDES SAMPAIO5 1Doutorando, Departamento de Engenharia de Biossistema, Universidade de São Paulo/ ESALQ, C.P. 09 – 13418-900 – Piracicaba, SP – Brasil. E-mail: diego_brand@hotmail.com2Professor, Departamento de Engenharia de Biossistema, Universidade de São Paulo/ ESALQ, C.P. 09 – 13418-900 – Piracicaba, SP – Brasil. E-mail: snduarte@usp.br3Professor Visitante, Departamento de Engenharia Agrícola e Ambiental, Instituto de Ciências e Tecnologia Agrícola, Universidade Federal de Mato Grosso, C.P. 78735-910 – Rondonópolis, MT – Brasil.  E-mail: jfvieira@usp.br4Doutorando, Departamento de Engenharia Agrícola, Programa de Pós-Graduação em Agronomia (Meteorologia Aplicada), Universidade Federal de Viçosa, C.P. 36570-900 – Viçosa, MG – Brasil.  E-mail: hugo.thaner@ufv.br5Doutorando, Departmento de Engenharia de Biossistema, Universidade de São Paulo/ ESALQ, C.P. 09 – 13418-900 – Piracicaba, SP – Brasil. E-mail: ramualyson@hotmail.com  1 RESUMO As pastagens constituem-se na principal forma de alimentação do rebanho bovino brasileiro. São escassas as informações na literatura acerca das respostas das forrageiras ao manejo da irrigação. Objetivou-se neste trabalho avaliar as trocas gasosas, a altura e a produção de fitomassa fresca e seca da parte aérea do capim-mombaça, sob diferentes níveis de água no solo. Adotou-se o delineamento de blocos aleatorizados, em dois experimentos utilizando de dois solos de texturas distintas: Nitossolo Vermelho (série “Luiz de Queiroz”) e Latossolo Vermelho Amarelo distrófico (série “Sertãozinho”); aplicou-se quatro níveis de depleção de água no solo (15, 30, 45 e 60%) com quatro repetições. A pesquisa foi realizada em casa de vegetação na Escola Superior de Agricultura “Luiz de Queiroz” - ESALQ/USP, no município de Piracicaba - SP. A umidade dos solos foi controlada por meio de pesagens diárias dos vasos de um bloco; foram realizados três cortes no capim. A taxa fotossintética, a altura das plantas e as fitomassas fresca e seca foram afetadas pela condição hídrica do solo; o nível de cerca de 30% de depleção de água no solo apresentou-se superior para as variáveis estudadas em ambos os solos. Palavras-chave: irrigação de pastagens, deficiência hídrica, taxa fotossintética  BRANDÃO, D.; DUARTE, S. N.; VIEIRA JOSÉ, J.; SANTOS, H. T. dos E PEDRO SAMPAIO, R. F.YIELD AND GAS EXCHANGES OF MOMBAÇA GRASS (Panicum maximum Jacq. cv. Mombaca) TO DIFFERENT LEVELS OF SOIL WATER DEPLETION    2 ABSTRACT The main form of feeding Brazilian cattle is through pastures. There is a lack of information about pasture responses under irrigation. The aim of this study was to evaluate gas exchanges, height and weight of green and dry mass of mombaça grass under different soil water levels.  Two experiments were set up in randomized blocks consisting of four levels of soil water depletion (15, 30, 45 and 60%) applied to two soils – Red Nitosol and Distrofic Yellow Red Latosol with four replications. The research was performed at “Escola Superior de Agricultura Luiz de Queiroz” – ESALQ/USP in greenhouse at Piracicaba - SP city.  Soil moisture was controlled by the weight of the experimental plots and the grass was cropped three times. Photosynthesis rate, height, green and dry weight of canopy were affected by soil water content; about thirty per cent of soil water depletion proportioned the better response for the studied variables for both soils. Keywords: pasture irrigation, water deficit, photosynthesis rate

De Stefano Piedade pela paciência e imensos ensinamentos em Estatística e Experimentação Agrícola; ao Prof. Ricardo Leite Camargo pelos grandes ensinamentos em docência no Ensino Superior e por ter sido um amigo nos momentos mais difíceis do mestrado. A banca examinadora pelas sugestões e críticas ao trabalho. Ao CNPq pela concessão da bolsa de mestrado (processo 130853/2014-3).

Most Brazilian cities do not have a proper water and soil management system due to lack of planning in this sector and of an easy-consultation local-hydrological bibliography capable of reinforcing the future creation of a hydrological modeling. Volta Redonda macro-region's case can be added to this statistics, since it accounts for several natural hazards linked to floods and inundations in some specific locations. The aims of the present study are to descriptively analyze monthly rainfall data generated by CEMADEN's rainfall gauges and to assess whether monthly rainfall in the region adapts well to probability Gamma Distribution plots. Rainfall data from four points in Volta Redonda, Barra Mansa and Pinheiral cities, recorded for 48 months, and provided by CEMADEN, were used in the study. Gamma Distribution was adjusted to monthly rainfall data. In conclusion, the probability of having a given monthly rainfall value lower than, or equal to, that recorded for the Pinheiral – Volta Redonda – Barra Mansa conurbation area can be estimated through Gamma Distribution. Values recorded for shape (γ) and scale (β) parameters of Volta Redonda macro-region's municipalities were 1.59 and 79.30, on average, respectively.