The effects of melatonin application by itself and mixed with sucrose solution on vase life and physicochemical changes in amaryllis cut flowers were investigated. Amaryllis stems with flower buds at harvest points were placed into vases containing different maintenance solutions: Melatonin (Mt; 0.01 mM), Sucrose (Suc; 4%), Melatonin + Sucrose (Mt + Suc; 0.01 mM + 4%) and distilled water (Control). Each treatment consisted of five repetitions, with one inflorescence stem per vase. The vases remained at 22 ± 3 °C and constant lighting of 13 µmol m^-2 s^-1 for 14 days. Immersion of stems in Suc or Mt + Suc delayed the initial senescence processes of the amaryllis cut flower. Vase life was prolonged for additional 2 days compared to stems immersed in water (control), increasing from 10 to 12 days of conservation. Floral stem mass was kept more stable; the degradation of anthocyanin and flavonoid pigments was delayed; and the stability of phenolic compounds and total carbohydrates was maintained for 14 days. These findings confirm the role of melatonin as a preservative in cut flowers. However, its preservative effect was potentialized by the addition of sucrose to the water of the amaryllis cut flowers. More work needs to be carried out to investigate the physiological mechanisms promoted by the interaction of melatonin and sucrose in the regulation of senescence in amaryllis cut flowers, including the analysis of gene expression and activity of the antioxidant system.

The present work aimed to study oxidative damage and protection, phenylpropanoid metabolism, and the quality of minimally processed colored sweet potatoes cultivated with increments in P₂O₅ fertilization. Sweet potato was cultivated with 0, 60, 120, 180, and 240 kg ha^-1 of P₂O₅. The roots were harvested, and the P content in the roots and leaves was quantified. The roots were minimally processed and kept for 20 days at 5 °C. In general, the roots that were fertilized with P₂O₅ showed a higher content of the analyzed variables. The highest P dosage in the soil increased the P content in roots and leaves and the agro-industrial yield. Roots cultivated with P₂O₅ showed a higher content of hydrogen peroxide, phenolic compounds, vitamin C, yellow flavonoids, anthocyanins, and carotenoids, antioxidant capacity by the DPPH method, and higher activity of the enzymes polyphenol oxidase, peroxidase, and phenylalanine ammonia lyase. These results demonstrated the role of phosphorus in protecting against oxidative damage due to the accumulation of bioactive compounds, thus improving the physicochemical quality of minimally processed orange sweet potato.

Combining refrigeration with packaging is a commonly used technique for fruits intended for export. Thus, the objective of this study was to adapt the post-harvest management of biofortified sweet potato cultivars, using packaging and refrigeration, focused on reaching distant export markets while maintaining the commercial quality. Sweet potatoes of the cultivars BRS-Amélia and Beauregard were selected after harvesting, washed, and packaged. The experimental design used was completely randomized, in a 4 × 7 factorial arrangement consisted of 4 treatments (cultivar BRS-Amélia with and without packaging; and cultivar Beauregard with and without packaging) and 7 evaluations under storage conditions: at 0, 7, 14 (under refrigeration at approximately 8 °C), 17, 20, 23, and 26 days (under room temperature conditions at approximately 25 °C). Each experimental unit contained 500 g of tubbers. The results showed that the refrigerated storage combined with packaging extended the shelf life of the evaluated sweet potatoes: 17 days for BRS-Amélia and 26 days for the cultivar Beauregard. The BRS-Amélia cultivar maintained higher firmness, soluble solids and carbohydrate contents, chroma, and antioxidant activity (FRAP method), and total phenolic contents, in both raw and cooked tissues. The cultivar Beauregard presented less dehydration and greater stability in vitamin C, total phenolic, total carotenoid, soluble carbohydrate, and starch contents in raw and cooked potatoes. Therefore, the combination of packaging and refrigeration preserved the commercial quality of biofortified sweet potatoes for export markets.

In recent decades, increasing environmental concerns have driven interest in sustainable polymers, such as the mucilage derived from forage cactus (Opuntia stricta), which shows significant potential for food applications and the production of biopolymeric films. To expand its industrial use, improvements in synthesis methods, additive incorporation, and agronomic practices are necessary. However, studies on the use of O. stricta in films produced under nitrogen fertilization remain scarce, underscoring the need for further research to fully explore its potential in the bioplastics industry. Cladodes of O. stricta fertilized with 50, 150, 300, and 450 kg N ha^–1 were washed, peeled, and ground with ethanol (99.8% P.A.) at a 2:3 ratio (parenchyma/alcohol), resulting in a dried mucilage powder used for analysis and film formulation. Lower nitrogen supply resulted in the highest cladode yield and produced mucilage with lower electrical conductivity, reduced sodium and potassium content, and a higher concentration of phenolic compounds, making it more suitable for antioxidant food applications. Films made from this mucilage demonstrated greater transparency, higher luminosity, increased stiffness, and reduced moisture content and water solubility. XRD and SEM analyses revealed a more crystalline and homogeneous structure, resulting in improved mechanical resistance. These outcomes indicate that nitrogen availability directly modulates mucilage composition and, consequently, the structural integrity and barrier properties of the films. The findings identify low nitrogen fertilization as a cost-effective and environmentally favorable strategy for producing consistent, high-quality biopolymeric films with potential applications in sustainable packaging.

In the semi-arid climate, the growth of fruit seedlings is challenged by the water stress characteristic of the region, which can restrict their development and, consequently, affect production. In this context, the aim was to assess the effect of pyroligneous extract on gas exchange characteristics, photosynthetic pigments, growth, and biomass of pitanga under different intensities of water deficit. The experiment was conducted using a randomized block design in a 3 × 2 factorial scheme, with four replicates, corresponding to water deficit periods (7 and 14 days) and control (daily irrigation), in substrates with and without pyroligneous extract. The plants were evaluated for gas exchange characteristics, chlorophyll indices, growth, and dry biomass. Application of pyroligneous extract after 7 days of water deficit increased the photosynthetic rate, carboxylation efficiency and Dickson quality index of pitanga seedlings by 40.04, 42.85 and 41.51%, respectively, compared to 14 days of water deficit. Pyroligneous extract was effective as a water stress attenuator in pitanga seedlings, especially during the first seven days of exposure to stress. Therefore, its application is recommended as a preventive and short-term measure to mitigate such effects on pitanga seedlings.

Using water with high salt concentrations in irrigated agriculture can affect sensitive plants’ metabolic and biochemical functions. Therefore, strategies are needed to minimize the adverse impacts of salt stress. This study aimed to evaluate radish plant growth, water relations, and biochemical and nutritional responses as a function of irrigation water salinity and exogenous ascorbic acid (AsA) application. The experiment was conducted in a controlled greenhouse under a completely randomized design in a 3 × 2 factorial scheme with four replicates, using one plant per experimental unit. Treatments consisted of three levels of irrigation water salinity (0.5, 3.0, and 5.0 dS m-1) and ascorbic acid application [without (0 mM) and with (1 mM)]. Increased salinity (3.0 and 5.0 dS m-1) affected growth, water status, biochemical traits, and nutrient accumulation in radish plants. Stem diameter (55.0%), shoot mass ratio (14.5%), relative growth rate (9.0%), and soluble sugars in shoot (29.8%) and root (47.6%) increased with 1 mM AsA application, especially at 5.0 dS m-1. Applying 1 mM AsA reduced Na⁺ and Cl⁻ cont 0ents in both shoot and root at all salinity levels and increased the Mg²⁺ content in shoot and root and Ca²⁺ content at 3.0 and 5.0 dS m-1.