RESUMOA água é um recurso natural que, nos últimos anos, tem sido alvo de inúmeras discussões quanto ao seu uso e disponibilidade. No setor agrícola o volume de água necessário à irrigação é calculado com base nas perdas ocorridas por evaporação e transpiração motivo por que este trabalho teve, como objetivo, determinar a evapotranspiração máxima e real da cana-de-açúcar irrigada por gotejamento. Os dados para esta pesquisa foram obtidos em um experimento conduzido na região de Rio Largo, AL, com sete tratamentos de irrigação (0; 25; 50; 75; 100; 125 e 150% da evapotranspiração de referência-ET0), em três ciclos de produção no período de janeiro de 2009 a fevereiro de 2012. A evapotranspiração real (ETr) foi estimada pelo Kc "dual". A ETr média na fase de crescimento máximo dos três ciclos variou de 1,73 a 5,04 mm d-1 nos tratamentos com 0 e 150% da ET0, respectivamente. A cana-de-açúcar em regime de sequeiro está, nesta região, exposta a médio risco climático, conforme classificação proposta na literatura.

The adequate water supply and nitrogen in the soil is essential for the growth and development of plants. Sunflower is the target of several studies of such factors due to the economic importance and the needs to expand in the semi-arid regions of Brazil. This work aimed to evaluate the growth variables, measured at 80 days after sowing (DAS), and the biomass obtained at 100 DAS of the Helio 253 sunflower hybrid under the effect of nitrogen and water levels. The experiment was conducted in a greenhouse in the city of Campina Grande-PB, in split-plot of a completely randomized design with four moisture levels in the soil (50, 75, 100 and 125% of available water) and four nitrogen rates (30, 60, 90 and 120 kg ha -1 ). Among all levels of available water in the soil, the stem diameter (SD) ranged from 13.6 to 19.6 mm and the plant height (PH) from 93 to 107 cm. Plants with 100% AW showed a leaf area (LA) 45% greater than the treatment with higher water stress. The heads had an average diameter between 83 and 98 mm, the dry biomass of the heads (DBC) and total dry biomass (TDB) ranged from 45 to 55 g and of 65 to 101 g, respectively. The weight of a thousand seeds per head (W1000) obtained minimum and maximum of 49 and 66 g. The stem diameter ranged between 14.4 to 18.3 mm and the minimum and maximum plant height values were 93 and 110 cm, using applied N levels. The leaf area varied from 22 to 36 dm 2 and the heads had average diameter of 86 to 99 mm. With respect to the dry biomass of the heads, there was a variation of 38 to 68 g and TDB of 68 to 107 g and W1000 valued between 52 and 65 g under doses of N. There is considerable variation in all variables mainly due to increased water level in the soil and nitrogen fertilization.

The objective of this study was to evaluate the physiology and production of sugar-apple as a function of irrigation intervals and foliar application of proline under the conditions of Paraíba’s semi-arid region. A randomized block design was laid out in a 4 × 2 factorial scheme, with treatments resulting from the combination of four irrigation intervals (1, 4, 8 and 12 days) and two concentrations of proline (0 and 10 mM), with four replicates, and the plot consisted of four usable plants. Increase in irrigation intervals reduced the gas exchange of sugar-apple plants at 298 days after transplanting. Exogenous application of proline at concentration of 10 mM increased contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids and fruit fresh mass in plants grown under 12-day irrigation intervals.

Given the quantitative scarcity of low-salinity water resources in the Brazilian semi-arid region, it is necessary to use water with a high concentration of salts. Thus, identifying salt-stress tolerant cultivars of crops is an alternative for expanding irrigated agriculture. The objective of this study was to evaluate the tolerance of passion fruit cultivars as a function of irrigation water electrical conductivity. The experimental design was randomized blocks, in a 5 × 3 factorial scheme, whose treatments consisted of the combination of five values of electrical conductivity of irrigation water - ECw (0.3, 1.1, 1.9, 2.7, and 3.5 dS m-1) and three sour passion fruit cultivars (BRS GA1, BRS SC1, and SCS437, with three replicates. Electrical conductivity of water from 0.3 dS m-1 reduces the relative water content, gas exchange, and the number of fruits and increased electrolyte leakage in the leaf blade of passion fruit plants, at 153 days after transplantation. The passion fruit cultivars BRS GA1, BRS SC1, and SCS437 were classified as sensitive, with threshold electrical conductivity of water of 0.3, 1.0, and 0.3 dS m-1, respectively.

CRESCIMENTO E RENDIMENTO AGRÍCOLA DA CULTURA DO MILHO SOB DIFERENTES DISPONIBILIDADES HÍDRICAS     MARCELO AUGUSTO DA SILVA SOARES1; SAMUEL SILVA2; JORGE LUIZ XAVIER LINS CUNHA3; ANA BEATRIZ DE ALMEIDA MOURA4; ANA CAROLINE DE ALMEIDA MOURA5 E ALLAN HEMERSON DE MOURA6   1 Doutorando em Produção Vegetal, Departamento de Tecnologia da Produção, Universidade Federal de Alagoas (UFAL), Av. Lourival Melo Mota, S/N, Tabuleiro do Martins, 57072-970, Maceió, Alagoas, Brasil, marcelocico_@hotmail.com. 2 Professor do Instituto Federal de Alagoas (IFAL), Campus Piranhas, Av. Sergipe, 1477, 57460-000, Piranhas, Alagoas, Brasil, samuel.silva@ifal.edu.br 3 Professor do Centro de Engenharia e Ciências Agrárias (CECA), Universidade Federal de Alagoas (UFAL), Av. Lourival Melo Mota, S/N, Tabuleiro do Martins, 57072-970, Maceió, Alagoas, Brasil, jorge.cunha.xavier@gmail.com 4 Graduando em Zootecnia pelo Centro de Engenharia e Ciências Agrárias (CECA), Universidade Federal de Alagoas (UFAL), Av. Lourival Melo Mota, S/N, Tabuleiro do Martins, 57072-970, Maceió, Alagoas, Brasil, anabeatrizamoura@gmail.com 5 Graduando em Agronomia pelo Centro de Engenharia e Ciências Agrárias (CECA), Universidade Federal de Alagoas (UFAL), Av. Lourival Melo Mota, S/N, Tabuleiro do Martins, 57072-970, Maceió, Alagoas, Brasil, anacarolineamoura@outlook.com 6 Mestrando em Produção Vegetal, Departamento de Tecnologia da Produção, Universidade Federal de Alagoas (UFAL), Av. Lourival Melo Mota, S/N, Tabuleiro do Martins, 57072-970, Maceió, Alagoas, Brasil, allanmoura.h@gmail.com.     1 RESUMO   O objetivo deste trabalho foi avaliar o efeito dos déficits e excessos hídricos no crescimento e rendimento agrícola do milho em diferentes épocas de cultivo na região de Rio Largo, AL. Para isso, foi conduzido um experimento no Campus de Engenharia e Ciências Agrárias da Universidade Federal de Alagoas. O delineamento foi em blocos casualizados, com quatro tratamentos e cinco repetições (E1= 28/05/14, E2-11/06/14, E3-25/06/14 e E4- 23/07/14). A primeira época de plantio foi a que apresentou maior altura do dossel (2,25 m), índice de área foliar (4,0 m2 m-2) e rendimento agrícola (8,03 t ha-1). A E4 apresentou a menor altura do dossel (0,9 m) e a menor produtividade agrícola foi observada na E3 (5,9 t ha-1). Isso aconteceu porque com base no balanço hídrico da cultura, quando o plantio é realizado até o primeiro decêndio de junho há uma melhor distribuição da chuva o que maximiza o potencial da cultura.   Palavras-chave: produtividade de grãos, precipitação pluvial, balanço hídrico     SOARES, M. A. S.; SILVA, S.; CUNHA, J. L. X. L.; MOURA, A. B A.; MOURA, A. C. A.; MOURA, A. H. GROWTH AND YIELD OF MAIZE CROP UNDER DIFFERENT WATER AVAILABILITIES       2 ABSTRACT   This work aimed to evaluate the effects of hydric deficits and excesses on growth and yield of corn  at different times of cultivation in the region of Rio Largo, Al. For this, an experiment was conducted at the Campus of Engineering and Agricultural Sciences of the Federal University of Alagoas. The statistical design was randomized blocks, with four treatments and five replications (E1 = 28/05/14, E2-11 / 06/14, E3-25 / 06/14, and E4- 23/07/14). The first planting season was the one with the highest canopy height (2.25 m), leaf area index (4.0 m2 m-2) and agricultural yield (8.03 t ha-1). The E4 had the lowest canopy height (0.9 m) and the lowest agricultural yield was observed in the E3 (5.9 t ha-1). This happened because based on the water balance of the crop, when planting is carried out until the first ten days of June, there is a better distribution of rain, which maximizes the crop's potential.   Keywords: yield of grains, rainfall, water balance