Studies on production factors of the irrigated organic cherry tomato in the Brazilian semi-arid region are just at the beginning phase. It mainly focuses on adequate irrigation management. Therefore, the aim of the present study was the technical and economic evaluation of some production factors like water and ground cover on cherry tomato. The climate of the region is of the BSw'h type, hot and semi-arid, with irregular rains distributed from February to May. The ground has fairly flat relief. The soil presents a sandy loam texture, well-drained, without risk of salinity and sodicity problems. The experimental design was of randomised blocks with three replications and subdivided plots, comprising five primary treatments in the plots and three secondary treatments arranged in the subplots. The primary treatments consisted of five levels of irrigation with 50, 75, 100, 125 and 150% of crop evapotranspiration, and three secondary treatments were assigned with ground covers of carnauba straw (CS), elephant grass (EG), plus a control treatment with no ground cover. The crop was irrigated by a system of drip irrigation. The results showed estimated slides equivalent to 454 mm (107% ETc loc), 461 mm (109% ETc loc) and 592 mm (140% ETc loc) can contribute to the highest commercial yield, corresponding to 11401, 10466 and 7802 kg ha-1 of cherry tomatoes for carnauba straw, elephant grass and uncovered soil, respectively. Carnauba straw presented potential as a vegetative cover, being economically feasible as it allowed a reduction in water consumption and yield of cereal tomato under poor irrigation strategy.

RESPOSTA DA CULTURA DO RABANETE SOB CULTIVO ORGÂNICO AOS FATORES DE PRODUÇÃO ÁGUA E COBERTURA DO SOLO     ANTONIO VANKLANE DE ALMEIDA1; ALEXSANDRO OLIVEIRA DA SILVA1; JENYFFER DA SILVA GOMES SANTOS2; JANIQUELLE DA SILVA RABELO3; VALSERGIO BARROS DA SILVA1 E ALFREDO MENDONÇA DE SOUSA1   1 Departamento de Engenharia Agrícola, Universidade Federal do Ceará, UFC, Av. Mr. Hull, s/n, Pici, CEP:60356-001, bloco 804, Fortaleza, Ceará, Brasil. E-mail: vanklaneprece@hotmail.com,  alexsandro@ufc.br, valsergiobarros@hotmail.com, alfredomendonca121@gmail.com    2 Faculdade de Engenharia Agrícola, Universidade Estadual de Campinas, UNICAMP, Av. Cândido Rondon, 501 - Cidade Universitária, CEP: 13083-875, Campinas, São Paulo, Brasil. E-mail: jnfgomes@gmail.com 3 Departamento de Fitotecnia, Universidade Federal do Ceará, UFC, Av. Mr. Hull, s/n, Pici, CEP:60356-001, bloco 805, Fortaleza, Ceará, Brasil. E-mail: janekellyrabelo@hotmail.com     1 RESUMO   Em regiões com limitações de recursos hídricos, como semiárido cearense, o uso eficiente da água torna-se a cada dia imprescindível para a produção de hortaliças irrigadas nestas regiões. Neste sentido, a presente pesquisa teve como objetivo a avaliação técnica e econômica do efeito dos fatores de produção água e níveis de cobertura do solo da bagana de carnaúba sobre a produtividade da cultura do rabanete. A pesquisa foi conduzida no período de junho a agosto de 2018 em dois ciclos de produção em área pertencente ao Prece (Programa de Educação em Células Cooperativas), localizado no município de Pentecoste-CE. O experimento foi conduzido em um delineamento em blocos casualizados com quatro repetições. Os tratamentos foram constituídos por cinco lâminas de irrigação (50%; 75%; 100%; 125% e 150% da evapotranspiração das culturas localizada, ETcloc) e cinco diferentes níveis de cobertura morta constituída de bagana de carnaúba:  25%; 50%; 75% e 100% além da testemunha com o solo sem cobertura 0%, totalizando 100 parcelas experimentais. Os resultados permitiram concluir que a bagana de carnaúba apresentou potencial para utilização como cobertura morta no cultivo de rabanete, proporcionando incremento no rendimento da cultura em condições de estratégia de irrigação com déficit para o uso de 16 t ha-1 de cobertura morta. A cultura rabanete responde de forma crescente às diferentes lâminas de irrigação até a ETcloc de 100%, podendo-se obter ganhos econômicos quando associadas à utilização de cobertura morta no solo.   Palavras-chave: Cobertura do solo. Manejo da irrigação. Função de produção. Raphanus sativus L.     ALMEIDA, A. V.; SILVA, A. O.; SANTOS, J. S. G.; RABELO, J. R.; SILVA, V. B.; SOUSA, A. M.  RESPONSE OF RABANET CULTURE UNDER ORGANIC CULTIVATION TO PRODUCTION FACTORS WATER AND SOIL COVERAGE         2 ABSTRACT   In regions with limited water resources, such as the semi-arid region of Ceará, the efficient use of water becomes indispensable every day for the production of irrigated vegetables in this region. In this sense, this research had as objective the technical and economic evaluation of the effect of the factors of production water and levels of the cover of the soil of the bagana on the productivity of the radish culture. The research was conducted in the period from June to August 2018 in two production cycles in area belonging to Prece (Cooperative Cell Education Program), located in the municipality of Pentecoste-CE. The experiment was conducted in a randomized block design with four replicates. The treatments consisted of five irrigation depth (50%, 75%, 100%, 125% and 150% of crop localized evapotranspiration, ET cloc) and five levels of ground cover consisting of carnauba bagana: 25%; 50%; 75% and 100% beyond the control with the soil without 0% coverage, totalizing 100 experimental units. The results allowed to conclude that the carnauba bagana presented potential for use as ground cover in the cultivation of radish, providing an increase in the yield of the crop under conditions of deficit irrigation strategy to use 16 t ha-1 of ground cover. The radish crop significantly responds to the different irrigation depth, up to 100% ET cloc, and economics gains can be obtained when associated with the use of ground cover in soil.   Keywords: Soil cover. Irrigation management. Production function. Raphanus sativus L.

This research addresses irrigation strategies for saving water, including the use of irrigation depths of 50, 75, 100, 125 and 150% of the crop evapotranspiration (ETc) and a ground cover of carnauba straw, in evaluating the response of the cherry tomato (Solanum lycopersicum var cerasiforme L) submitted to different levels of water availability in soil with and without ground cover, in the semi-arid region of northeastern Brazil. The physiological components showed higher values under ground cover and when submitted to 100% ETc. The greatest number of total and commercial fruit was obtained when the soil was covered, and irrigated with depths of 75 and 100%. Carnauba straw with irrigation depths of 100 and 125% resulted in the greatest fresh fruit weight. The highest values for fruit diameter and length were achieved in the soil under cover. Maximum productivity, 11,404.20 kg ha-1, was obtained at 107.5%, while for the soil with no ground cover, maximum productivity was 7,778.86 kg ha-1, obtained with an irrigation depth of 140%. Based on the results, soil productivity is possible without a cover of carnauba straw, at an irrigation depth of 50.5%, which can generate savings of 3400 m³ water-cycle-1 ha-1. In addition, water use efficiency in the cherry tomato was 3.06 kg m-3 and 1.95 kg m-3, with and without ground cover respectively. It can be concluded that the use of carnauba straw makes it possible to reduce water consumption in the 'red' cherry tomato under conditions of water scarcity.

Characterised as a traditional technique for the production of food and biomass, intercropping is a practice mainly used by small rural producers. In general, the practice has sought to maximise the use of environmental resources in an area, as well as to promote the ecological balance of different ecosystems. The aim of this study was to evaluate the performance of radish intercropped with coriander in a region of semi-arid climate. The experimental design was of randomised complete blocks, with five replications per treatment: 1) ‘Cometo’ radish intercropped with coriander, 2) monocropped ‘Cometo’ radish, 3) ‘Saxa’ radish intercropped with coriander, 4) monocropped ‘Saxa’ radish, and 5) monocropped coriander. The coriander and/or radish plants from each treatment were harvested 30 days after sowing. The following parameters were evaluated in the radish: number of leaves per plant, fresh shoot weight, shoot length, taproot length, taproot diameter, taproot weight and productivity; while in the coriander the following were evaluated: number of stems per plant, fresh shoot weight, shoot length and productivity. The Area Equivalence Efficiency (AEE) was also evaluated for the main crop. The ‘Saxa’ radish showed the highest productivity, both as a single crop and when intercropped (15.40 and 14.32 t ha-1 of root, respectively). AEE values were greater than 1 in both intercrops, 2.13 and 1.70 for the intercropped ‘Cometo’ and ‘Saxa’ radish respectively, showing this cropping system to be an important way of optimising coriander cultivation in the area of study.