RESUMO O uso de tela de sombreamento no cultivo de hortaliças sensíveis ao excesso de radiação, associado ao uso eficiente de água via irrigação, possibilita ganhos de produtividade. Objetivou-se avaliar características de rendimento de tomate cereja cultivado com e sem o uso de tela de sombreamento e diferentes lâminas de irrigação. Utilizou-se delineamento em blocos casualizados, em esquema fatorial 4 x 2, com quatro lâminas de irrigação (140 %, 160 %, 180 % e 200 % da evapotranspiração de referência - ETo) e dois híbridos de tomate cereja (Wanda e Dolcetto). A lâmina de irrigação correspondente a 200 % da ETo proporcionou maiores valores para número de flores e cachos formados, número de frutos por planta e diâmetro de fruto. O híbrido Wanda foi mais frutífero, com maior emissão de cachos, enquanto o Dolcetto mostrou-se mais florífero. O uso de tela de sombreamento no cultivo de tomate cereja proporciona incremento nas características de rendimento, se comparado ao cultivo em áreas abertas.

ABSTRACT The use of shading screen in vegetable crops sensitive to the radiation excess, associated with the effective water use via irrigation, allows for yield gains. This study aimed to evaluate the yield characteristics of cherry tomato cultivated with and without shading screen and different irrigation levels. A randomized block design was used, in a 4 x 2 factorial arrangement, with four irrigation levels (140 %, 160 %, 180 % and 200 % of the reference evapotranspiration - ETo) and two cherry tomato hybrids (Wanda and Dolcetto). The irrigation level corresponding to 200 % of the ETo provided the highest values for number of flowers and clusters formed, number of fruits per plant and fruit diameter. The Wanda hybrid was more fruitful, with a higher emission of clusters, while Dolcetto was more floriferous. The use of shade screen for cultivating cherry tomato provides an increase in the yield characteristics, if compared to the cultivation in open areas.

ABSTRACT This study’s objective was to assess the response and effectiveness of irrigation management systems for the production of bell pepper with different agricultural substrates, under protected conditions. The current study was conducted in a greenhouse located in Juazeiro, BA, in the northwest of Brazil. The experiment design was completely randomized in a split-plot system, with two irrigation treatments as the main plots (the drainage lysimeter and the Piché evaporimeter) and two substrates in each sub-plot (coconut fiber and pinus bark), with 5 replications per treatment. Harvest was conducted from 86 to 151 days after transplanting, and the following characteristics were evaluated: total, marketable and unmarketable yields, production per plant, fresh mass of fruits, fruit number per plant, length and diameter of fruits, length/diameter ratio, water use efficiency, pulp thickness, fruit pH, soluble solids, and titratable acidity. No interaction effects between irrigation treatments and substrates were observed on the following variables: total yield, marketable yield, non-marketable yield, production per plant, mean mass, and diameter of marketable fruits. Irrigation treatments and substrates did not show a significant effect on bell pepper yield. Drainage lysimeter-based management and coconut fiber substrate had the best results in terms of the physical quality of fruits, whereas pinus bark-based substrate positively influenced all chemical variables and the Piché evaporimeter-based irrigation management showed a good performance raising fruit pH in relation to fruits cultivated in lysimeter with pinus bark. Additional research is required under different environmental conditions so that this crop fully expresses its yield potential.

Resumo Dados de experimento de campo conduzido em parreirais de uva de mesa da variedade Festival em Petrolina-PE, no período de 19 de setembro a 12 de outubro de 2010 foram usados para avaliar a influência da cobertura plástica sobre as condições microclimáticas de parreirais na Região do Vale do Rio São Francisco. Estudaram-se três tratamentos: dosséis sem cobertura plástica (WC); com cobertura plástica posicionada a 50 cm de altura (PC50); e a 100 cm de altura (PC100). Os resultados indicaram que a cobertura plástica impediu a passagem de cerca de 40% da radiação global, reteve a umidade relativa no interior dos dosséis, gerou aumento de temperatura do ar e acentuada redução da velocidade do vento sobre o dossel PC50. No entanto, o tratamento PC100 teve maior incidência de onda curta e saldo de radiação sob dossel (sobre as bagas) do que os tratamentos WC e PC50, resultando em condições climáticas mais favoráveis, proporcionando cerca de 40% a mais de produtividade neste tratamento. Portanto, o parreiral com a cobertura plástica posicionada a 100 cm de altura representa uma alternativa mais adequada às condições climáticas da região do Vale do São Francisco.

Abstract Data from field experiments conducted in table grape vineyards variety of Festival in Petrolina-PE in the period from September 19 to October 12, 2010 were used to evaluate the influence of plastic cover on microclimate conditions of vineyards in São Francisco River Valley region. Three treatments were studied: canopies without plastic cover (WC); with plastic cover positioned at 50 cm (PC50), and at 100 cm (PC100) above canopy. The results indicate that the plastic cover prevented the passage of about 40% of the global and net radiation, retained the relative humidity inside the canopy, generated an increase of air temperature and marked reduction in wind speed over the canopy of treatment PC50. However, treatment PC100 had a higher incidence of short wavelength and net radiation under canopy (on the berries) than WC and PC50 treatments, resulting in more favorable weather conditions, providing about 40% greater productivity in this treatment. Therefore, the vineyard with plastic cover placed at 100 cm above canopy represents a more suitable alternative to the climatic conditions of the region of the São Francisco River Valley.