Andres Felipe Gaona Acevedo

Pitaya (dragon fruit) has gained increasing commercial interest due to its nutritional value and bioactive potential. This study characterized seven pitaya varieties (‘Costa Rica’, ‘Nicarágua’, ‘Purple Haze’, ‘Physical Graffiti’, ‘Imperial’, ‘Connie Mayer’, and ‘Golden de Israel’) regarding physicochemical attributes of the pulp and biochemical and mineral composition of peel and pulp tissues. Physicochemical parameters, color attributes, betalains, flavonoids, total phenolic compounds, antioxidant activity (DPPH, ABTS, and FRAP), and mineral nutrients were evaluated, followed by principal component and hierarchical cluster analyses. Red-fleshed varieties (‘Costa Rica’ and ‘Nicarágua’) exhibited higher betalain contents, whereas purple-fleshed varieties (‘Purple Haze’ and ‘Physical Graffiti’) showed greater phenolic and flavonoid concentrations and higher antioxidant activity. Both peel and pulp showed favorable mineral profiles, particularly for potassium and iron. ‘Physical Graffiti’ presented the highest mineral macronutrient levels, while ‘Connie Mayer’ exhibited the highest micronutrient contents. These results highlight the nutritional and functional potential of pitaya fruits and their by-products for food applications.

Among the most cultivated crops worldwide, potato ( Solanum tuberosum) faces significant threats from water scarcity, owing to its shallow root system and high irrigation requirement. Water deficit disturbs homeostasis and critical physiological mechanisms, including photosynthesis, carbohydrate translocation, and starch metabolism in tuberous plants. It reduces CO₂ assimilation, modulates the expression of key enzymes involved in starch synthesis, such as ADP-glucose pyrophosphorylase and starch synthases, and alters the amylose–amylopectin ratio, consequently affecting their rheological properties. Additionally, drought triggers antioxidant and metabolic responses in plants, including the accumulation of secondary metabolites and the regulation of stress tolerance-related genes. Transcriptomic analyses have revealed water-deficit responsive genes, such as StMAPK11 , StCDPK13 , and StERF94 , which contribute to stress adaptation. This review also explores mitigation strategies and genetic improvement approaches, including the application of biostimulants (chitosan, uniconazole), ZnO and SiO₂ nanoparticles, and the selection of more drought-tolerant genotypes. Recent advances in biotechnology, including gene editing and omics technologies, have contributed to the development of stress-resilient potato varieties.

Climate change and the resulting abiotic stresses that emerge due to anthropogenic activities are the main causes of agricultural losses worldwide. Abiotic stresses such as water scarcity, extreme temperatures, high irradiance, saline soils, nutrient deprivation and heavy metal contamination compromise the development and productivity of crops on a global scale. In this scenario, understanding the response of C₄ plants to different abiotic stresses is of utmost importance, as they constitute major pillars of the global economy. To further our understanding of the response of C₄ monocots, Setaria viridis and Setaria italica have gradually emerged as powerful model species for elucidating the physiological, biochemical, and molecular mechanisms of plant adaptation to abiotic stresses. This review integrates recent findings on the morphophysiological, transcriptomic, and metabolic responses of S. viridis and S. italica to drought, elevated heat and light, saline soils, nutrient deficiencies and heavy metal contamination. Comparative analyses highlight conserved and divergent stress-response pathways between the domesticated S. italica and its wild progenitor S. viridis. Together, these findings reinforce Setaria as a versatile C₄ model for unraveling mechanisms of abiotic stress tolerance and highlight its potential as a genetic resource for developing climate-resilient cereal and bioenergy crops.

Climate change and the resulting abiotic stresses that emerge due to anthropogenic activities are the main causes of agricultural losses worldwide. Abiotic stresses such as water scarcity, extreme temperatures, high irradiance, saline soils, nutrient deprivation and heavy metal contamination compromise the development and productivity of crops on a global scale. In this scenario, understanding the response of C4 plants to different abiotic stresses is of utmost importance, as they constitute major pillars of the global economy. To further our understanding of the response of C4 monocots, Setaria viridis and Setaria italica have gradually emerged as powerful model species for elucidating the physiological, biochemical, and molecular mechanisms of plant adaptation to abiotic stresses. This review integrates recent findings on the morphophysiological, transcriptomic, and metabolic responses of S. viridis and S. italica to drought, elevated heat and light, saline soils, nutrient deficiencies and heavy metal contamination. Comparative analyses highlight conserved and divergent stress-response pathways between the domesticated S. italica and its wild progenitor S. viridis. Together, these findings reinforce Setaria as a versatile C4 model for unraveling mechanisms of abiotic stress tolerance and highlight its potential as a genetic resource for developing climate-resilient cereal and bioenergy crops.

In fleshy fruit species such as those of the Cucurbitaceae plant family (e.g., zucchini), the storage or resting after harvest of the fruits enables the seeds to complete their maturation process, reaching maximum levels of germination and vigor. The proper resting period can allow early harvestings, improve the agronomic uses of the area, and reduce seed exposure to weathering and the attack of insects and microorganisms. This study evaluates zucchini seed quality after postharvest resting periods. Zucchini fruits harvested 63 days after transplanting were maintained for 0, 3, 6, 9, or 12 days before seed extraction. The percent of processed seeds (clean and whole seeds), the weight of 100 seeds, germination, first count in germination, germination speed index, electrical conductivity, nitrogen (N), and protein contents were evaluated. Data generally fitted positive linear regression models, increasing the weight of 100 seeds, percent of processed seeds, germination, vigor, seed N, and protein as the resting period after harvest (days) increases. Seed electrical conductivity decreased as days of postharvest rest increased. After the harvest of the zucchini fruits, the resting period positively affected the production of homogeneous and high-quality zucchini seeds.

Constant changes during the seed maturation process affect its final quality and the post-harvest fruit resting, which can improve seed physiological quality. Therefore, the objective of this study was to evaluate the physiological and enzymatic activities of eggplant seeds extracted from fruits harvested at different ages and resting periods after harvest. Fruits were harvested presenting different colors at 40, 50, 60, and 70 days after anthesis (DAA) and rested for 0 (freshly harvested fruits), 10, and 20 days. The experimental design was set as completely randomized, with four replications and evaluated seeds extracted from six fruits per plot. The resting periods in eggplant fruits harvested at less than 60 DAA improved the mass of 1000 seeds, germination, vigor, and protein content. Seeds with higher germination and vigor presented lower dismutase (SOD), catalase (CAT), and peroxidase (POX) enzymatic activity. The results indicated that the ideal moment of eggplant harvest for seed production is when the fruit reaches the yellowish-brown color corresponding to about 60 DAA; however, if the eggplant fruit is harvested earlier (40 or 50 DAA), it has to rest for about 10 to 20 days to achieve high physiological quality (germination and vigor).

A romã é conhecida por seus efeitos benéficos a saúde, principalmente por suas propriedades antioxidantes e é amplamente cultivada em diferentes regiões do mundo, o que reflete na grande diversidade de composição dos frutos. Desta forma o objetivo do presente trabalho foi avaliar as características físicas, físico-químicas, bioquímicos e composição centesimal da romã cv. Comum cultivada no Oeste Paulista. Os frutos utilizados foram colhidos no estádio de maturação comercial, no município de Alvares Machado, região de Presidente Prudente, estado de São Paulo e avaliados quando ao peso, firmeza, coloração, pH, sólidos solúveis (SS), acidez titulável (AT), Ratio (SS/AT), compostos fenólicos totais, atividade antioxidante por DPPH, antocianina monomérica total, composição mineral, umidade, cinzas, proteínas, lipídeos, fibras, açúcares redutores e valor calórico total. Os frutos de romã cv. Comum apresentaram a casca de coloração laranja e polpa (sarcotesta) vermelho-violeta. O potássio (K) foi o macronutriente predominante na casca e na polpa. A polpa apresentou alto teor de sólidos solúveis e baixo teor de acidez titulável, caracterizando sabor adocicado. A casca apresentou maior teor de compostos fenólicos totais e atividade antioxidante em relação a polpa. A polpa apresentou maior valor calórico total.