The excess of salts can affect several processes in the crops, and nitrogen (N) can attenuate the depressive effect of salinity. The objective was to evaluate the influence of nitrogen doses on the growth and gas exchange of corn crop irrigated with saline water. The experiment was conducted from June to September 2019 at the University of International Integration of Afro-Brazilian Lusophony, Redenção, CE, Brazil. The experimental design was completely randomized, in a 2 x 3 factorial scheme (supply water of 0.3 dS m-1 and saline solution of 3.0 dS m-1) and three nitrogen doses, 0, 80, and 160 kg ha-1, corresponding to 0, 50, and 100% of the recommended dose respectively, with six repetitions. At 30 and 45 days after sowing (DAS), plant height, leaf area, number of leaves, photosynthesis, transpiration, and stomatal conductance were evaluated. Saline stress affects plant height, leaf area, photosynthesis, transpiration, and conductance at 30 DAS. The doses of 80 and 160 kg ha-1 provide greater performance in plant height, leaf area, photosynthesis, transpiration, and conductance at 30 DAS. The use of low salinity water and doses of 80 and 160 kg ha-1 were more efficient in terms of plant height, leaf area, photosynthesis, transpiration, and conductance at 45 DAS. The dose of 160 kg ha-1 of N attenuates the harmful effects of salts in AG 1051 hybrid maize plants, providing higher values of photosynthesis, transpiration, and stomatal conductance at 45 DAS when irrigated with water of 3.0 dS m-1.

This work evaluated the effects of water salinity on the physiological indices in inoculated and non-inoculated peanut plants. The study was carried out in a protected environment at the seedling production unit (UPMA) at Campus das Auroras, at the University for International Integration of the Afro-Brazilian Lusophony (UNILAB), Redenção, Ceará. The experimental design used was in a completely randomized (CRD), with treatments in a factorial arrangement, 5x2, referring to the five salinity levels of the irrigation water - CEa: 0.5, 1.5, 3, 4.5, and 6.0 dSm-1, and inoculated and non-inoculated plants with a mix of rhizobia SEMIA 630, lot 0810, and SEMIA 6144, lot 0312, from Bradyrhizobium sp., isolated, with four replications. Recommended fertilization was done for phosphorus (62.5 kg ha-1 of P) and potassium (50 kg ha-1 of K) to supply the nutritional needs of the plants. The nutritional effect caused by symbiosis with Bradyrhizobium sp. favored inoculated plants to present greater tolerance to salt stress. The availability of nitrogen collaborated to increase the efficiency of plant physiological mechanisms. Uninoculated plants, even with a higher amount of chlorophyll and CO2, were not efficient in the photosynthetic rate. Saline stress affected photosynthesis, transpiration, stomatal conductance, internal CO2 concentration, water use efficiency, and chlorophyll; however, with less intensity when inoculated with Bradyrhizobium sp. The increase in salinity on irrigation water increased the leaf temperature.

A deposição de coberturas mortas em sistema plantio podem afetar diretamente componentes de vegetativos e coeficientes de produção de hortaliças. O rabanete por ser uma planta de pequeno porte e fácil produção e comercialização, detém poucas alternativas mais orgânicas de produção, com isso o presente trabalho buscou avaliar o crescimento e índices de coeficientes de produção do Raphanus sativus L. cultivado em diferentes tipos de cobertura morta vegetal. O trabalho foi desenvolvido ambiente protegido com telado de 50% preto, na Unidade de Produção de Mudas das Auroras (UPMA) no Campus das Auroras na Universidade da Integração Internacional da Lusofonia Afro-Brasileira (UNILAB), Redenção, Ceará, na região do Maciço de Baturité. O delineamento experimental foi de blocos casualizados (DBC), com tratamentos arranjados em quatro blocos e cinco repetições, totalizando 20 unidades experimentais. Foram quatro tratamentos, sendo T1-palha de arroz, T2-bagana de carnaúba, T3-mulching e T4-testemunha. As variáveis analisadas no crescimento foram diâmetro de caule, área foliar, número de folhas e altura de plantas e no período de produção foram comprimento da raiz, diâmetro da raiz e massa da raiz. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey com p < 0,05, se utilizou o programa SISVAR 5.0 e posteriormente correlacionados com Pearson com o programa EXCEL 2016 para adsorver os resultados da pesquisa   A bagana de carnaúba e o mulching se destacaram em relação ao solo com outras coberturas como os materiais que proporcionaram melhores valores de componentes de produção.

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In the present work, a recurrent selection program was initiated, between and within half-sib families in landrace maize, with the objective of obtaining, at the end of the process, a productive maize variety for agroecological cultivation systems adapted to the northeast region. A base population composed of 10 landrace varieties donated by farmers the region. In the base population, 60 half-sib families were selected. These were grown for selection among families, in Capistrano/CE, at Fazenda Repouso das Águas, in the agricultural year 2017/2018, in randomized blocks with three replications. It was used as a witness for a variety of BRS-Caatingueiro. The selection within the families was carried out in the agricultural year 2018/2019 at the Fazenda Experimental Piroás located in the municipality of Redenção/CE. 15 characteristics were evaluated in the selection among and 10 in the within families. In the selection between, the average production and productivity was 5.033,90 kg.ha-1 and 4.316,04 kg.ha-1, respectively. The superiority in relation to the witness was 8.67%. In the selection within, the average production and productivity was 4.448,413 kg.ha-1 and 3.998,41 kg.ha-1, respectively.