RESUMOO uso de águas salinas na agricultura é um dos principais fatores que limitam a produção e a qualidade dos frutos no Estado do Rio Grande do Norte, sendo a seleção de híbridos tolerantes à salinidade e a utilização de adubação nitrogenada, alternativas para se evitar perdas de rendimento e qualidade desses frutos. Assim, o objetivo com este trabalho foi avaliar o comportamento produtivo e a qualidade dos frutos de três cultivares de melancia (Quetzali, Shadow e Leopard) submetidas a diferentes salinidades da água de irrigação e doses de nitrogênio, na região de Mossoró, RN. Os tratamentos consistiram em aplicação de água de irrigação com cinco condutividades elétricas (0,57; 1,36; 2,77; 3,86 e 4,91 dS m -1 ) e três doses de nitrogênio (48, 96 e 144 kg ha -1 ), delineados em blocos casualizados, com quatro repetições. Foram avaliados a produtividade, o número e o peso médio dos frutos e o teor de sólidos solúveis. O peso médio e o número de frutos influenciaram as perdas de rendimento das cultivares de melancia estudadas; apenas a cultivar Shadow apresentou o teor de sólidos solúveis dos frutos alterado com a salinidade da água de irrigação. Palavras-chave:Citrullus lanatus L., cultivares, condutividade elétrica, adubação nitrogenada Production and quality of watermelon cultivated with water of different salinities and doses of nitrogen ABSTRACT The use of saline waters in the agriculture is one of the main factors that limit the production and the fruit quality in the State of Rio Grande do Norte, being the selection of tolerant hybrids to salinity and the use of the nitrogen fertilization, alternatives to avoid losses in income and quality of the fruits. Therefore, the objective of this study was to evaluate the production and the quality of the fruits of three cultivars of watermelon (Quetzali, Shadow and Leopard) under different salinities of irrigation water and doses of nitrogen in the region of Mossoró, RN. The treatments consisted in the application of irrigation water with five electrical conductivities (0.57; 1.36; 2.77; 3.86 e 4.91 dS m -1 ) and three doses of nitrogen (48, 96 e 144 kg ha -1 ), delineated in randomized blocks, with four replications. The productivity, the number and the mean weight of fruits, as well as the content of soluble solids were evaluated. The mean weight of fruits and the number of fruits affected the loss of income of studied watermelons cultivars. Only the Shadow cultivar had the soluble solids content of fruits altered with the salinity of irrigation water.

No abstract

The present study aimed to evaluate the agronomic performance of the sunflower crop irrigated with treated domestic wastewater and normal water (well-water) in a inceptisol of Apodi, State of Rio Grande do Norte, Brazil. The experiment was conducted in a randomized block experimental design, consisting of five treatments and five replications, using the H-251 sunflower cultivar from Embrapa. The treatments consisted of the application of five proportions of wastewater/well-water (T1-100% wastewater; T2-75% wastewater and 25% well water, T3-50% wastewater and 50% well-water, T4-25% wastewater and 75% well-water and T5-100% well-water plus chemical fertilizer, control). The variables such as plant height, leaf number, diameter of stem and the head, yield, oil production, thousand-grain weight and head weight were evaluated. The combined use of wastewater and well-water is an alternative for the substitution of mineral fertilization with minimal damage to the productive potential and development of the sunflower crop. In general, the T4 treatment was the most adequate to improve agronomic performance of the sunflower.

No abstract

No abstract