A B S T R A C TThe objective of the present study was to evaluate the response of eggplant, cv. 'Ciça' , with respect to yield, number of fruits and dry matter (root and stem), when grown in a greenhouse and conducted under fertigation with nitrogen and potassium. Resposta da cultura da berinjela fertirrigada com doses de nitrogênio e potássio R E S U M O Objetivou-se, no presente estudo, avaliar a resposta da cultura da berinjela, cultivar Ciça, com relação à produtividade, número de frutos e massa seca (raiz e caule), quando cultivada em ambiente protegido e conduzida sob fertirrigação com nitrogênio e potássio. O experimento foi conduzido no Centro Técnico de Irrigação da Universidade Estadual de Maringá, entre os meses de fevereiro e agosto de 2015. Foram testadas quatro doses de nitrogênio (0,0; 6,43; 12,86 e 25,72 g de N planta -1 ) e quatro doses de potássio (0,0; 5,18; 10,36 e 20,73 g de K planta -1 ), perfazendo 16 tratamentos em esquema fatorial 4 x 4, dispostos em delineamento inteiramente casualizado com quatro repetições, em Latossolo vermelho distrófico, de textura arenosa. O maior número de frutos por planta e produtividade foi obtido na dose entre 14-17 g de N planta -1 (145-177 kg ha -1 ). Doses isoladas de potássio não influenciaram estatisticamente a produtividade nem a massa seca de raiz.

This study aimed to investigate the effect of irrigation with saline water on fruit quality, yield, and plant nutrition of tomato (Lycopersicon esculentum Mill.) cultivars. Tomato cultivation was carried out under protected environment conditions in a double row system with drip irrigation performed according to the demand of the plants. Commercial fruit weight, commercial fruit number, fruit yield, absorption of Ca, N, P, S, K, and Mg were all affected by saline irrigation. The leaf Na concentration and the concentration of total phenolic compounds, total titratable acids, total soluble solids, vitamin C, carotenoids, and flavonoids in the fruits were favored from the increase in irrigation salinity. The Na+ causes a deficiency of Ca, which impairs seed formation in tomato fruits, as Ca is a structural element in the formation of the pollen grain. The Onix genotype had the highest yield, weight, and number of commercial fruits under control and moderate salt stress conditions. Saline water impaired nutrient absorption and improved tomato fruit quality. Under salt stress, tomato plants were able to absorb and translocate large amounts of Na+ to the shoot and even improved the organoleptic quality of fruits, increasing the content of carotenoids, flavonoids, vitamin C, total phenolic compounds, total soluble solids, and total titratable acids of tomato fruits. The clustering analysis was able to show the highest genetic dissimilarity between the group composed of Shanty, Maestrina, and Ipa 6 and the group with Sheena, Totalle, and Pizzadoro under salt stress conditions; also, it evidenced the greater stability of these genotypes.

-Fertilization is important for the optimization of plant growth and yield, which are necessary for agronomic activities. Soil fertilization should increase net earnings that depend on nutrient use efficiency. The aim of this study was to evaluate the agronomic efficiency of eggplant under different doses of potassium (K) and nitrogen (N). Four levels of K (0, 54, 108, and 216 kg ha -1 ) and four levels of N (0, 67, 134, and 268 kg ha -1 ) were applied weekly by fertigation. The highest plant and the largest stem diameter were found with 165-175 kg ha -1 of N. Leaf area was more influenced by N than by K. Isolated application of different K doses did not statistically influence height plant, stem diameter, or leaf dry matter. The agronomic efficiency of nitrogen is reduced with increasing levels of N and K.

No abstract

This study aimed to evaluate the benefits of irrigation with magnetically-treated water and replacement depths based on ETc, in plant growth and development of bell pepper grown in a protected environment in two cultivation seasons. The experiment was carried out in a protected environment, in the Centro Técnico de Irrigação (CTI), at Universidade Estadual de Maringá (UEM), in Maringá - PR. Two experiments were performed: summer (2017-2018) and winter-spring (2018). The experimental design adopted was randomized blocks in factorial scheme 3 x 2 (six treatments) with four replications in the summer season and 2 x 2 (four treatments) with six replications in the winter-spring season. The first factor consisted of water replacement depths (50, 75 and 100% of the evapotranspiration of culture (ETc) in the summer season, and 75 and 100% ETc in the winter-spring season. The second factor was the application of water with and without magnetic treatment. Characteristics of growth (plant height, stem diameter, leaf area, and dry matter of stem, leaf, total, and root) and development (first flower and first fruit) were evaluated. Results showed that there was no significant interaction between the factors for the summer season. There were only isolated effects of replacement depths, and the 100% ETc had the highest values for the growth variables, independent of water treatment. The application of magnetically-treated water provided higher accumulation of dry matter (stem, total, and root) when irrigated with 75% ETc for the winter-spring season.

Resistência mecânica do solo à penetração avaliada em área de segundo ano de implantação da cultura da mandioca (Manihot esculenta CRANTZ) Mechanical resistance of soil to penetration evaluated in the second year of implantation of cassava (Manihot esculenta CRANTZ)

The use of magnetizers for the treatment of irrigation water can be used in agriculture as an alternative to increase the growth and yield of several crops. The objective of this study was to evaluate the effect of different irrigation depths and magnetic treatment of water on eggplant crop cultivated in protected environment. The study was carried out in two experiments, in the first one, the design was completely randomized with four replications and two factors: water depths (50, 75 and 100% ETc) for two water qualities (water treated by magnetizers and water without treatment). In the second one, the design was completely randomized with five replicates and two factors: water depths (75 and 100% ETc) for two irrigation water treatment (water treated by magnetizers and water without treatment). In the second experiment was ignored the treatment of 50% of ETc in order to increase the number of repetitions to check if there are differences between water treated to water without treatment. There were no significant differences in eggplant yield and growth as function of the magnetic treatment of water. The water depth that provided the highest yield, number of fruits per plant and stem dry matter in the two experiments was 100% ETc regardless of water quality.

The cultivation of bell peppers, before transplanting, starts in nurseries to obtain uniform and vigorous seedlings. This study aimed to evaluate the effect of applying magnetically treated water on germination and the initial growth of bell pepper seedlings. Two experiments were conducted from August to October 2018 in a protected environment at the Irrigation Tecnic Center (CTI/ UEM) -Maringá, Paraná: the first in 50-cell polyethylene trays and the second in plastic containers (180 ml). Both experiments were filled with a commercial substrate (Su) and commercial substrate + soil mix (SS). The substrate was irrigated daily for the germination test, according to the corresponding treatment, and germination was quantified in the first 15 days after emergence to obtain the germination percentage and the final emerged percentage. Seedling growth was evaluated based on the following criteria at 43 days after sowing: height, stem diameter, total fresh mass, total dry mass, chlorophyll A and B, and carotenoids. The results showed that the application of magnetically treated water to seeds promoted germination one day prior to those irrigated without treatment when cultivated with SS. There was significant interaction for the chlorophyll A, with a 42% increase in SS cultivation with the application of magnetically treated water compared to the application of non-treated water. For the other variables, there were significant responses only in SS cultivation. Application of magnetically treated water caused higher gravimetric humidity in three out of ten evaluations, showing a significant reduction of evaporation in Su and SS cultivation.