Resumo Objetivou-se quantificar o consumo hídrico de duas cultivares de atemoia, em pomares irrigados, pelo método da sonda de dissipação térmica (SDT), relacionando a transpiração com a área foliar e a demanda evaporativa da atmosfera. O experimento foi realizado em dois pomares de atemoia com plantas jovens e adultas, das cultivares Gefner e African Pride, no campo experimental da Universidade do Estado da Bahia, em Juazeiro-BA. Determinou-se o fluxo de seiva das plantas por meio de SDT e do crescimento vegetativo; bem como foram obtidas as variáveis meteorológicas. O fluxo de seiva nas plantas de atemoia, no pomar jovem, atingiu valores máximos de 10,2 e 8,4 L planta-1dia-1, nas cultivares Gefner e African Pride, respectivamente. Nas plantas do pomar adulto, esses valores foram de 50,1 L planta-1,dia-1 na Gefner, e de 98,2 L planta-1dia-1, na African Pride. A relação entre o fluxo de seiva e a área foliar apresentou linearidade apenas para determinada faixa de área foliar, em ambas as cultivares e pomares. A estimativa do fluxo de seiva, a partir do produto da área foliar e da evapotranspiração de referência, pode ser utilizada desde que sejam considerados os limites de área foliar em que essa relação ocorre, em cada variedade.

Abstract The aim of this study was to quantify the water consumption of two atemoya cultivars in irrigated orchards using the thermal dissipation probe (TDP) method, relating transpiration with leaf area and evaporative demand of the atmosphere. The experiment was carried out in two atemoya orchards with young and adult plants of ‘Gefner’ and ‘African Pride’ cultivars at the experimental field of the University of the State of Bahia, in Juazeiro-BA. Plants sap flow was determined by TDP and vegetative growth, and meteorological variables were obtained. The sap flow of young atemoya plants reached maximum values of 10.2 and 8.4 L plant-1 day-1, in ‘Gefner’ and ‘African Pride’ cultivars, respectively. In adult plants, these values were 50.1 L plant-1 day-1 in ‘Gefner’ cultivar and 98.2 L plant-1 day-1 in ‘African Pride’ cultivar. The relationship between sap flow and leaf area showed linearity only for a given leaf area range, in both cultivars and orchards. Sap flow estimated from the product between leaf area and reference evapotranspiration can be used provided that the leaf area limits in which this relationship occurs, in each variety, are considered.

ABSTRACT The objective of this work was to evaluate the behavior of Crisphead lettuce as a function of production seasons under different forms of protected environment. Two experiments were carried out in the field at different times: September to December 2017 and June to August 2018, in a randomizaed blocks desing, in a 4 x 7 factorial scheme, the first one being production environments under shade nets: red screen, chromatinet® screen, black screen and full sun, and the second, lettuce cultivars: Winslow, Irene, Balsamo, Rafaela, Iron Wood, Great Lakes and Delícia. The harvest was carried out at forty-two days after transplanting, where the following variables were analyzed: stem length (cm), total production and commercial productivity (t ha-1). The data were submitted to analysis of variance, and a joint analysis was performed to analyze the treatments effect, then the means were compared by the Scott-Knott test, at 5% probability. The microclimate was altered in the shaded beds, which affected the cultivars development. The cultivation in protected environment provides higher productivity of Crisphead lettuce from September to December, at that time the cultivars Balsamo and Delicia were highlighted under chromatinet®. In the period of mild temperatures, a better performance was observed for cv. Balsamo in full sun.

ABSTRACT. The current scenario of increased water scarcity is due to climate change and directly affects food production. It is thus necessary to develop strategies to mitigate the impacts of low water availability. Therefore, the goal of the present study is to evaluate the physiological behaviour of melon cultivars under water stress. The experiment was conducted in a protected environment in the experimental Submedium region of the São Francisco River Valley in the period ranging from October to December. In this study, we used the melon cultivars 'Amarelo' and 'Piel de Sapo'. The experiment was conducted in a randomized block design with three replicates that were subdivided into plots, where the plots were comprised of four irrigation rates (50, 75, 100, and 125% of crop evapotranspiration - CET), subplots were comprised of the two melon cultivars, and sub-subplots were comprised of samplings for physiological analyses (15, 30, and 45 days after transplanting). The parameters evaluated were stomatal conductance, transpiration, net photosynthesis, relationship CI/CA, and accumulated dry matter. Water stress reduced the stomatal conductance, transpiration, net photosynthesis, CI/CA, and accumulated dry matter. 'Piel de Sapo' showed a higher photosynthetic adjustment than 'Amarelo' melon due to the gas exchange behaviour of the former, and it was, therefore, more tolerant to water stress.

O objetivo deste trabalho foi avaliar o efeito das condições de deficit hídrico, na fase de maturação da uva, sobre a produção e qualidade da uva 'Superior Seedless' entre julho e novembro de 2007. O experimento foi realizado em delineamento de blocos ao acaso, com quatro repetições, em arranjo fatorial (3x3) + 1: três épocas de alteração da aplicação das lâminas de irrigação (21, 13 e 5 dias antes da colheita); três lâminas de irrigação (100, 50 e 0% da evapotranspiração da cultura); e um tratamento controle (manejo de irrigação adotado pelo produtor). As épocas de irrigação e as lâminas de irrigação utilizadas influenciaram a firmeza das bagas e a acidez titulável. A interrupção da irrigação, aos 13 ou 21 dias antes da colheita, resultou em produtividade, qualidade de frutos e eficiência do uso da água semelhante às obtidas pelo produtor, assim, pode ser adotada para economia da água de irrigação na Região do Submédio do Vale do São Francisco.

The objective this work was to evaluate the effect of water deficit conditions, during the maturation phase of grapes, on the production and quality of the 'Superior Seedless', between July and November of 2007. The experiment was carried out in a randomized block design, with four replicates, in a (3x 3) + 1 factorial arrangement: three times of alteration of the irrigation depths (21, 13 e 5 days before harvest); three irrigation depths (100, 50 e 0% of crop evapotranspiration); and a control treatment, which was the producer's irrigation management scheme. Irrigation timing and depth influenced berry firmness and titrable acidity. The management with cut-off irrigation depths at 13 or 21 days before harvesting and the control had the same yield, grape quality and water use efficiency, and may be adopted to save water for irrigation in the São Francisco Valley region.

A Caesalpinia pyramidalis Tul. é ima espécie nativa da catinga resistente à seca e de grande potencial econômico. A germinação das suas sementes compreende uma série de processos, que começa com a embebição de água e termina com a emergência da plântula através do tegumento. Iniciada a germinação das sementes, ocorre a ativação de enzimas hidrolíticas pré-existentes e a síntese denovo.de outras enzimas hidrolíticas que induzem a mobilização das reservas. Pouco se conhece sobre a velocidade de embebição e metabolismo germinativo desta espécie, portanto o objetivo deste trabalho foi obter a curva de embebição e avaliar as alterações bioquímicas que ocorrem nas sementes de catingueira durante a germinação. As sementes foram separadas em três repetições de 20 sementes para cada tempo de embebição, que foi de uma, duas e três horas e, posteriormente a cada três horas até 72h. As sementes foram colocadas em "gerbox", sobre duas camadas de papel embebido em 15mL de H2Od. Antes e após o tempo de embebição, as sementes foram pesadas. Em seguida, o material foi congelado para análise de açúcares solúveis totais (AST), açucares redutores (AR), amido, proteínas totais (PT), e as proteínas de reserva: globulinas, prolaminas, albuminas e glutelinas. A curva de embebição das sementes de catingueira apresentou modelo trifásico, onde a fase (F) I foi completada em 24h e a FIII iniciou-se após 54h de embebição. Os teores de AR nas sementes aumentam durante a embebição, enquanto os teores de AST diminuem e de amido permanecem constante. As proteínas de reserva, os teores de albuminas, globulinas e prolaminas aumentam durante a embebição. Por outro lado os teores de glutelinas diminuem na FI e permanecem constantes durante FII e FIII.

Caesalpinia pyramidalis Tul. is a native species for caatinga biome, with a great resistance to drought and with great economic potential. The seeds germination comprehends cascade processes that start with the water imbibition and ends with the seedling emergence through the seed tegument. Once it starts, the activation of pre-existing hydrolytic enzymes and the denovo synthesis if other hydrolytic enzymes, leading to reserves mobilization. Little is known about the imbibition rate and germinative metabolism of C. pyramidalis, therefore the objective of this wok was to obtain the imbibition curve and evaluate biochemical changes that take place during germination of C. pyramidalis. Three replication of twenty seeds were subjected to each imbibition period, which were 1, 2, 3 hours (H) and after that at intervals of 3h until 72h. The seeds were placed in gerbox over two layers of germination paper moisten in 15mL of distilled water. Before and after each imbibition period the seeds were weighted and frozen until extraction and analysis of the contents of total soluble sugars (AST), reducing sugars (AR), starch and reserve proteinas (albumine, globuline, prolamine and gluteline). The imbibition curve fo C. pyramidalis seeds presented triphasic model, in wich phase (F) I was completed after 24h and FIII initiated after 51h imbibition, following root protrusion at 54h. The AR content increases during imbibition, while AST decreases and starch stays relatively constant during imbibition. Regarding the reserve proteins, albumine, globuline and prolamine increased during imbibition and, inversely, gluteline decreased during FI and remains constant during FII and FIII.