Talinum fruticosum is a species confirmed to occur in the semi-arid region, considered an unconventional food plant with a high protein content and tolerant to temporary periods of water restriction. This study aimed to evaluate water deficit as a strategy for growing Talinum fruticosum, covering physiological and biochemical aspects. The experimental design adopted was entirely randomized, using six treatments and eight replications. The treatments were defined as water availability (WA) 0 (no water replenishment), 20, 40, 60, 80, and 100%, conducted in a greenhouse, with water replenishment every 7 days. After 21 days, the centesimal composition, water relations, gas exchange, and biochemical aspects were evaluated. The energy value of the dry biomass of T. fruticosum leaves was directly influenced by the water content in the soil, and the water deficit led to an increase in protein. Water restriction compromised the species' water status and performance, mainly limiting gas exchange by reducing the water content in the soil, compromising CO₂ gain. It also led to increased biomolecules, with the highest contents seen in the treatments without water replacement (0%) and for 20% WA. Therefore, reducing the WA to 40% could be a strategy adopted to increase the protein content in the leaves of T. fruticosum, promoting an increase in the centesimal composition of proteins, a reduction in gas exchange, and an increase in the content of biomolecules.

Water deficit is the main cause of abiotic stress to which plants are susceptible, whether cultivated or those that are underexploited, such as Physalis peruviana L. Searching for tools that contribute to the management of water deficit in plants is fundamental for the maintenance of agriculture, especially in arid and semi-arid areas around the world. Thus, the objective of this study was to evaluate the effect of chemical priming with proline and sodium nitroprusside as promoters of increased tolerance to water deficit in P. peruviana plants. Plants grown under well hydrated conditions (FC of 70±5%) were sprayed with proline (10 and 20 mM) or sodium nitroprusside (25 and 50 μM) and evaluated after exposure to water deficit (FC of 20±5%). Plants cultivated under water deficit without pretreatment showed reductions in the variables of water relations, gas exchange and growth. Proline and sodium nitroprusside were effective in maintaining less negative water potential, contributing to improvements in gas exchange, such as CO2 assimilation, stomatal conductance and transpiration. Thus, it was possible to measure greater tolerance to water deficit in pretreated plants and, consequently, greater biomass accumulation. It appeard that pretreatment of proline and sodium nitroprusside can have a priming effect against water deficit in P. peruviana plants.

O objetivo deste trabalho foi analisar a disponibilidade hídrica através do Balanço Hídrico Climatológico e realizar a Classificação Climática, pelo método de Thornthwaite para o município de Bom Jesus da Lapa, Bahia. Para elaboração do Balanço Hídrico Climatológico foram utilizados dados mensais de precipitação e temperatura sendo esses dados provenientes de uma série de 38 anos, pertencente ao Instituto Nacional de Meteorologia. Foi adotado o valor de 100 mm para a capacidade de água disponível no solo (CAD). A Classificação Climática utiliza os dados de excesso e deficiência hídrica anual obtida do Balanço Hídrico Climatológico. Os resultados obtidos mostraram que a temperatura média anual foi de 26,37 ºC e a precipitação média anual é de 792,66 mm. Os meses de Janeiro a Novembro compreendem o período de deficiência hídrica, enquanto que Dezembro é representado por reposição hídrica. Quanto a Classificação Climática, o município possui o clima C1 w2 A’ a’ que corresponde ao clima sub-úmido seco com grande deficiência hídrica no inverno, megatérmico com concentração de evapotranspiração potencial no verão igual a 36,64% em relação à evapotranspiração anual.

In acidic soils, one of the main factors limiting crop yield is the presence of aluminum. However, some species may exhibit tolerance and mitigate the toxic effects of this element. This study aimed to evaluate and compare machine learning algorithms for the predictive analysis of aluminum ion accumulation sites, using the Evans blue dye to assess its interaction with root morphology, in cowpea genotypes. A completely randomized design, with five aluminum concentrations (0, 50, 100, 150 and 200 µM of AlCl₃·6H₂O) and fourteen cowpea genotypes, was used. Significant variations in aluminum tolerance were observed among the genotypes, with MNC06-908-39 and MNC06-895-1 being classified as the most sensitive, whereas MNC06-907-29 and MNC06-901-14 exhibited a higher tolerance. CB-27 was identified as the most tolerant overall, whereas MNC06-909-54, MNC06-909-55, MNC06-907-35, MNC06-908-39 and MNC06-909-76 were considered the highest sensitive ones. The quantitative dye analysis corroborated the qualitative findings, confirming the higher aluminum tolerance of the MNC06-907-29 and MNC06-901-14 genotypes, whereas MNC06-908-39 and MNC06-895-1 were the most sensitive ones. A predictive analyses, using the Random Forest, Decision Tree, k-Nearest Neighbors and Neural Network algorithms, demonstrated a clear genetic variability among the genotypes in response to aluminum stress, with the Neural Network showing the highest predictive accuracy.

Studies aimed at identifying genotypes tolerant to water deficit are essential for the development of superior plant materials adapted to regions with limited water availability, such as the Brazilian Semi-Arid. This study evaluated the physiological, biochemical, and enzymatic responses of Stylosanthes spp. subjected to different levels of water availability (60%, 40%, and 20% of pot capacity). The experiment was conducted using a completely randomized design using a 3 × 2 factorial scheme, comparing the accession BGF 11-001 and the cultivar BRS-Bela (cv. Bela). Physiological traits, biochemical variables, and antioxidant enzyme activity were analyzed. The accession BGF 11-001 showed resilience under water deficit, maintaining high chlorophyll content even under severe stress. This response was associated with increased accumulation of amino acids such as proline, as well as enhanced antioxidant activity, indicating a tolerance mechanism based on osmotic adjustment and cellular protection. In contrast, cv. Bela exhibited higher sensitivity to water stress, with a pronounced reduction in photosynthetic pigments and greater accumulation of compatible solutes, including total soluble proteins, reducing sugars, amino acids, and proline, without significant activation of antioxidant enzymes. Overall, the results demonstrate that the genotypes adopt distinct strategies to cope with water stress, with BGF 11-001 being more efficient in activating defense mechanisms. Therefore, BGF 11-001 has agronomic potential for cultivation in drought-prone regions and is a promising genetic resource for forage breeding programs aimed at improving drought tolerance.

Drought is the primary stress factor in semiarid environments. Consequently, selecting plant genetic resources capable of tolerating temporary periods of water scarcity, such as Physalis angulata, becomes essential. This study aimed to identify P. angulata accessions with potential for use under water deficit conditions by evaluating plant water status and physiological and biochemical responses. Five accessions, including two from Bahia (BA1 and BA2), Pará-PA, Rio de Janeiro-RJ, and Piauí-PI, were grown under well-watered and water deficit conditions. Relative water content, gas exchange parameters, and organic solute accumulation were assessed. All accessions exhibited changes in plant water status and reductions in CO₂ assimilation, stomatal conductance, and leaf transpiration under water deficit. The accumulation of compatible solutes varied among accessions, with notable contrasts between Bahia accession 2 and Pará accession, particularly for total soluble sugars and reducing sugars. These findings highlight the complexity of the species and the distinct mechanisms underlying its response to limited water availability. Overall, gas exchange was the trait most sensitive to water restriction, followed by alterations in biochemical attributes. Therefore, the Physalis angulata accessions from Bahia accession 2 and Pará accession show potential for use under water-deficit conditions and could provide valuable insights, particularly through transcriptome analysis.