Among the fruit plants cultivated in Brazil, papaya (Carica papaya L.) stands out by having high productivity of fruit quality. The seedling production system of this culture needs a technology that promotes the production of plants with high physiological and sanitary quality. Thus, we aimed to evaluate the growth, dry matter accumulation and the efficiency of water use of papaya cultivars under doses of bovine biofertilizer in hydroponic culture. We used a completely randomized design with eight treatments in a factorial scheme 4 x 2, with six replications, and a useful plant per repetition totalizing 48 useful plants.

The objective was to evaluate leaf area and gas exchange of okra plants for different irrigation depths, organic matter content and mulch. The activities were conducted in an experimental area of the State University of Paraíba, Campus IV, Catolé do Rocha-PB. An experimental design with randomized blocks, treatments distributed in a factorial 2 × 5 × 2 related to two irrigation levels, 100 and 50% of crop evapotranspiration (ETc), five levels of organic matter in the soil (1.8, 2.8, 3.8, 4.8 and 5.8%) and soil with and without mulch, totaling 20 treatments replicated in four blocks, was used. The experimental unit consisted of 27 plants. The increase of soil organic matter stimulated growth in leaf area and the gas exchange of okra plants. The irrigation with the smallest depth of water inhibited the expansion of leaf area, but provided a greater efficiency in okra's gas exchange. Mulch alleviated the reduced effects of irrigation water depth and stimulated the activity of okra gas exchanges.

This study aimed to evaluate the effect of irrigation with saline water and phosphate fertilization on phytomass accumulation and tissue mineral composition of cowpea shoots. The research was carried out in a greenhouse utilizing randomized block design in a 5 x 3 factorial scheme consisting of five levels salinity of irrigation water (0.5 as control, 1.5, 2.5 3.5 and 4.5 dS m-1) and three doses of P2O5- (60, 100 and 140% from a recommended dose of 60 kg P2O5- ha-1), with 5 replicates. The plants were grown in pots up to flowering and then phytomass accumulation and mineral composition of cowpea (indicate cultivar name) shoot were measured. Irrigation with saline water from 0.8 dS m-1 reduced phytomass accumulation and mineral composition of cowpea plants, making the plants to be considered moderately tolerant up to EC 2.5 dS m-1. The 40% increase in recommended phosphorus dose promotes high iron and copper accumulations and, less sodium accumulation into tissues of cowpea shoot as influenced by saline stress. 60% reduction of the recommended dose of phosphate fertilizer increased the manganese and zinc accumulation of tissues of cowpea shoot under salt stress.

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The Sunflower plant is an oilseed of great importance on the world stage. However, their productivity may be compromised by lack of rain and availability of nutrients. Thus this study aimed to evaluate the growth of sunflower plants under different hydric regimes in two soils with the application of cattle biofertilizer. The experiment was performed in a greenhouse State University of Paraíba campus IV in Catolé do Rocha, Paraíba, Brazil. The treatments were arranged in a completely randomized design using a 2 × 2 × 5 factorial for two levels of water availability (100 and 50% WA), two soils Entisol and Alfisol and five rates of cattle biofertilizer (0.0, 2.5, 5, 7.5 and 10% of the substrate volume), totaling 20 treatments with nine replications and 180 experimental plots. At 90 days after sowing the plants were evaluated for growth and biomass accumulation. The reduction from 100 to 50% WA negatively affected the vegetative behavior of the plants in both soils. The increased growth and biomass accumulation occurred with the application of biofertilizer rates of 3.5 and 10% (v/v) in Entisol and Alfisol, and respectively.

Noni has been introduced in Brazil just over a decade ago. Therefore, the information regarding crop fertilization and its influence on fruit quality is rare in the literature. Among macronutrients, potassium is highly concentrated in noni plants, and fertilization with cattle manure contributes to plant nutrition and fruit quality. This study sought to evaluate the effect of potassium fertilizer and cattle manure on the physical and physicochemical attributes of noni fruits. The treatments were distributed in randomized blocks, with four replications and two plants per plot, arranged in a factorial design 5 × 2 related to 0, 13.2, 37.5, 61.5 and 69.6 g plant -1 potassium chloride doses in soils without and with 12 kg plant -1 of cattle manure, with a C/N = 18:1 ratio. Cattle manure increased the average fruit weight from 99.6 to 113.4 g, expressing an increase of 13.9% for plants without and with organic compounds. Potassium chloride provided an increase of 61% in fruit weight and 31.25% in titratable acidity in fruits of plants without and with the highest dose of potassium chloride. Potassium chloride and cattle manure increased fruit mass, fruit length, fruit diameter, pulp mass, vitamin C and glucose contents in noni fruits.