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Okra (Abelmoschus esculentus) is sensitive to the salinity of water and soil, a common abiotic stress in the semiarid region of northeastern Brazil; however, such sensitivity is variable with water management in the soil-plantatmosphere system. Thus, the objective was to evaluate the fertilization with nitrogen-potassium combinations in okra cultivated under salt stress. Photosynthetic pigments, gas exchange, growth and fruit quality were evaluated. Fertilization with N1:K1 (40% N + 40% K2O) reduced the damage caused by salt stress and increased the chlorophyll contents, while the application of N4:K4 (130% N + 100% K2O) decreased the damage caused by salt stress and increased the carotenoid contents. The combination of N:K fertilization did not affect gas exchange, however, salt stress decreased these variables. Fertilization with N2:K2 (70% N + 60% K2O) reduced the damage caused by salt stress and increased the leaf area of okra. In addition, salt stress decreased the number of fruits and increased the fresh mass of okra fruits. The N:K fertilization also reduced the damage caused by salt stress and in the soluble solids content, titratable acidity, SS/TA ratio, and ascorbic acid content. Thus, N:K fertilization can be seen as an important agronomic strategy to improve the performance of okra quality subjected to saline conditions. [ABSTRACT FROM AUTHOR]

'Pera' orange is a scion variety widely grown in commercial orchards of various citrus-producing regions in Brazil due to the good acceptance of its fruits by the consumer market, both for fresh consumption and industrial processing. The development of clones or selections occurs by genetic mutations within genetic improvement studies with the different varieties, consisting of the selection of plants with superior quality and production characteristics to the variety of origin. In this perspective, this study aimed to evaluate the physicochemical characteristics of four 'Pera' orange selections ('D9', 'D12', 'D25', and 'C21') grafted on two rootstocks (Rangpur lime (Citrus limonia Osbeck) and 'Volkamer' lemon (Citrus volkameriana Tan. and Pasq.), under the semi-arid conditions of the São Francisco Valley, Brazil. The experimental design was completely randomized, in a 4 x 2 factorial arrangement, with the first factor corresponding to the orange selections ('Pera D9', 'Pera D12', 'Pera D25', and 'Pera C21') and the second factor corresponding to the Rangpur lime and 'Volkamer' lemon rootstocks, using five replications of 10 fruits. The physical characteristics evaluated were: fruit mass (g), diameter, and length (mm); fruit firmness (Lb), peel thickness (mm), number of seeds, and juice yield (%). The chemical parameters were determined through the contents of vitamin C, soluble solids (°Brix), and titratable acidity (g of citric acid 100 mL-1), also calculating the maturation index (SS/TA ratio). The interaction between rootstock varieties and orange scions (selections) induced differences in the physical and chemical attributes of fruits, with the Rangpur lime rootstock inducing better fruits for the orange selection 'Pera D-9', which showed the highest values of fruit mass and diameter, associated with thicker peels, lower soluble solids content, lower acidity, and higher vitamin C content, while inducing higher values of fruit length and soluble solids content in the fruits of the orange selection 'Pera C-21', and lower number of seeds and higher juice yield for the orange selection 'Pera D-12'. Based on these results, under these conditions, the physical and chemical characteristics observed in the fruits of the 'Pera' orange selections meet the standards required by the market of fresh fruits. [ABSTRACT FROM AUTHOR]