Explore the vast range of titles available.

Currently, biostimulants in the horticultural sector are a tool that is being used to improve the yield and quality of vegetables under optimal and stressful growth conditions. In the present study, we evaluate the effects of foliar application of a hydroethanolic extract of Sargassum spp., a commercial extract based on Ascophyllum nodosum, and a control with distilled water on growth and biomass, stomatal conductance, photosynthetic pigments, enzymatic and non-enzymatic antioxidants, protein content, and the expression of defense genes in tomato plants (Solanum lycopersicum L.) without stress and with high-temperature stress (45 °C). The results showed that Sargassum spp. extract only increased the height of tomato plants under stress-free conditions (2.71%) in the last evaluation. The aboveground and total dry biomass of the plants were increased by Sargassum spp. extract under stress-free conditions by 9.56 and 8.58%, respectively. Under stress conditions, aboveground dry biomass was increased by 6.66% by Sargassum spp. extract. Stomatal conductance, photosynthetic pigments, protein content, enzymatic and non-enzymatic antioxidants, and defense gene expression of tomato plants were positively modified with the use of Sargassum spp. and A. nodosum extract under high-temperature stress conditions. Under stress-free conditions, the described variables were positively modified except for gene expression, where some genes were expressed and others were repressed. The results indicate that extracts of Sargassum spp. and A. nodosum are effective in mitigating high-temperature stress, making their use a promising alternative for inducing resistance in plants to the daily adversities of climate change.

The increasing demand for agricultural products free from synthetic inputs has driven the development of sustainable strategies that enhance crop production, improve quality, and promote the reuse of agro-industrial residues. In this context, the present study aimed to evaluate the effect of a biofertilizer based on calcium carbonate (CaCO₃) nano powder, synthesized via green methods using maguey (Agave spp.) residues, on the agronomic quality of cucumber (Cucumis sativus L.) fruits. The nanobiofertilizer was applied as a foliar spray at concentrations of 0 (control), 20, 30, and 40 mg L-¹. A completely randomized experimental design was used for the agronomic and production variables with three concentrations of CaCO3 and a control. For the post-harvest variables, a completely randomized design with a factorial arrangement of dates 1, 2 and 3 and three concentrations of CaCO3 and a control (3X4) was used for the post-harvest quality variables. The application of the treatments significantly improved key agronomic parameters compared to the control: plant height increased by 26%, stem diameter by 41%, fruit weight by 44%, and yield by 53%. Additionally, fruit firmness was enhanced by 49%, and calcium content in the fruits increased by 17%. These results support the use of soluble calcium sourced from valorized agave bagasse as a sustainable alternative for enhancing cucumber production.

Selenium (Se) is a beneficial nutrient for plants and its application as seed priming is associated with positive effects on their growth. The use of Se occurs in ionic or nanometric form, however, another possible use is in micrometric form, which to our knowledge has not been studied in plants. The objective of the study was to evaluate the seed priming of cucumber (Cucumis sativus L.) with sodium selenite (Na2SeO3), nanoparticles (SeNPs) and Se microparticles (SeMPs) at concentrations of 0, 0.1, 0.5, 1.0, 1.5 and 3.0 mg L-1 of Se, for each of the mentioned forms. Growth, biomass, vigor, biomolecules and nutrients were evaluated in cucumber seedlings grown in a growth chamber for 15 days. The results showed increases in seedling length and biomass for all Se forms, which was reflected in increases in vigor indices from 21.42% to 27.72% for vigor index 1 (length) and from 16.96% to 34.5% for vigor index 2 (biomass), with SeMPs standing out at 1.0 and 1.5 mg L-1. Regarding pigments, variable effects were observed, where some treatments did not modify the concentration of chlorophylls and carotenoids (SeMPs) and others negatively affected (SeNPs and Na2SeO3). Reduced glutathione increased from 13.48% to 31.59%, with SeMPs standing out at 1.0 and 1.5 mg L-1. Phenols, flavonoids, proteins, S, K and Mg were also increased with the different Se materials; however, P, Ca, Fe, Zn, Cu and Mn decreased with some Se treatments. The results indicate that it is advisable to apply Na2SeO3, SeNPs and SeMPs, mainly SeMPs at 1.0 and 1.5 mg L-1.

Tomato fruits are a unique functional food and a natural reservoir of nutrients, antioxidants, vitamins and bioactive compounds that improve nutrition and human health. As an important vegetable throughout the world, tomatoes have attracted the attention of researchers to carry out various strategies to improve the functionality of this food aimed at the prevention of diseases, health and global well-being. An agronomic strategy in this study was to evaluate the influence of the application of \"salicylic acid (SA)\" on the yield and nutraceutical quality of the tomato crop, produced under hydroponic conditions. A completely randomized experimental design with six repetitions was used. SA at five doses (0.025, 0.05, 0.075, 0.1 and 0.125 mM) and one control were applied every 15 days in the nutritive solution under a hydroponic system on tomato plants. The evaluated variables were yield (total fruit weight per plant), fruit parameters (weight, diameter, firmness, and total soluble solids), percentage of weight loss and nutraceutical quality of tomato. The results obtained indicate that the addition of salicylic acid in nutritive solution increased the yield and biosynthesis of phytochemical compounds in tomato fruits, in relation to the control without application. In conclusion, to obtain a higher nutraceutical quality without affecting the tomato fruit yield, it is recommended to use the average concentration (0.125 mM) of SA.

Currently, the use of biostimulants in agriculture is a tool for mitigating certain environmental stresses. Brown algae extracts have become one of the most important categories of biostimulants in agriculture, and are derived from the different uses and positive results obtained under optimal and stressful conditions. This study aimed to examine the efficacy of a foliar application of a hydroalcoholic extract of Sargassum spp. and two controls (a commercial product based on Ascophyllum nodosum and distilled water) with regard to growth, the antioxidant system, and the expression of defense genes in tomato seedlings grown in nonsaline (0 mM NaCl) and saline (100 mM NaCl) conditions. In general, the results show that the Sargassum extract increased the growth of the seedlings at the end of the experiment (7.80%) compared to the control; however, under saline conditions, it did not modify the growth. The Sargassum extract increased the diameter of the stem at the end of the experiment in unstressed conditions by 14.85% compared to its control and in stressful conditions by 16.04% compared to its control. Regarding the accumulation of total fresh biomass under unstressed conditions, the Sargassum extract increased it by 19.25% compared to its control, and the accumulation of total dry biomass increased it by 18.11% compared to its control. Under saline conditions, the total of fresh and dry biomass did not change. Enzymatic and nonenzymatic antioxidants increased with NaCl stress and the application of algal products (Sargassum and A. nodosum), which was positively related to the expression of the defense genes evaluated. Our results indicate that the use of the hydroalcoholic extract of Sargassum spp. modulated different physiological, metabolic, and molecular processes in tomato seedlings, with possible synergistic effects that increased tolerance to salinity.

The growing demand for food production and increasing stress scenarios increase the crucial need for sustainable alternatives to achieve increased crop yield and quality without affecting the environment. The use of brown macroalgae, being a renewable resource, is a promising option with various application options in agricultural systems, mainly in the form of extracts, direct applications, and compost. Brown algae are a source of active biomolecules and minerals that are currently used as agricultural biostimulants, since they increase crop productivity. This type of biostimulants derived from brown algae improve seed germination, increase the accumulation of plant biomass by accelerating cell division and elongation, activating the antioxidant system of plants, making them more resistant to stress, and contributes to the absorption and translocation of nutrients present in the soil. These products are also compatible with other agricultural inputs, such as synthetic fertilizers and pesticides, which makes them ideal for comprehensive applications and maintaining a balance in agroecosystems. This review incorporates fundamental and applied aspects of brown seaweeds that impact yields, biochemical quality, physiology, stress mitigation, and soil properties. Based on the above, the review is divided into different Sections that show the formulation of brown seaweed products; their effect on crop yield, quality, and physiology; their effect on biotic and abiotic stress mitigation; and their impact on soil physical, chemical, and biological properties.

The use of elicitors or biostimulants such as salicylic acid (SA) is an emerging novel practice to improve the yield and quality of crops since it plays an important role in the regulation of various physiological and metabolic processes. The objective of this research was to study the effect of the foliar application of SA on the nutraceutical quality and yield of tomato fruits. A completely randomized experimental design with 10 repetitions was used. SA was applied at five doses (0.025 mM, 0.05 mM, 0.075 mM, 0.1 mM, and 0.125 mM) every 15 days through foliar sprays after transplantation, accumulating seven applications through the cycle. The response variables were yield (total fruit weight per plant), fruit parameters (weight, diameter, firmness, and total soluble solids), percentage of weight loss, and nutraceutical quality. The obtained results suggest that the foliar spraying of SA improves the yield and biosynthesis of phytochemical compounds in tomato fruits, compared to control plants. According to the results, it is advisable to use the dose of 0.125 mM of SA since it has a higher content of bioactive compounds without compromising yield.

Selenium (Se) is a nutrient that is considered beneficial for plants, because its improvement in growth, yield and quality helps plants to mitigate stress. The objective of this research was to evaluate the application of sodium selenite (Na2SeO3), nanoparticles (SeNPs) and microparticles (SeMPs) of Se in cucumber seedlings, via two experiments: one with seed priming and the other with foliar application of Se materials. The doses used were: 0, 0.1, 0.5, 1.0, 1.5 and 3.0 mg · L−1, for each form of Se and for each form of application. Treatment 0 consisted of the application of distilled water, which was used as a control. The results indicated that the SeMPs treatment at 3.0 mg · L−1 for seed priming had the greatest effect on stem diameter and leaf area. Foliar application of SeMPs at 1.5 mg · L−1 was the most effective at increasing the leaf area. In terms of fresh and dry biomass (aerial, root and total) for seed priming, all the treatments were superior to the control, and SeMPs at 1.5 and 3.0 mg · L−1 caused the greatest effects. With foliar application, fresh root biomass improved to a greater extent with the SeMPs treatment at 3.0 mg · L−1, and dry biomass (aerial, root and total) increased with the SeMPs at 1.0 and 3.0 mg · L−1. With respect to the photosynthetic pigments, proteins, phenols and minerals, the Se treatments, both for seed priming and foliar application, caused increases and decreases; however, reduced glutathione (GSH) increased with treatments in both forms of application. The Se concentration in the seedlings increased as the dose of Se material increased, and greater accumulation was achieved with foliar application of SeNPs and SeMPs. The results indicate that the use of Se materials is recommended, mainly the use of SeMPs, which improved the variables studied. This opens new opportunities for further studies with SeMPs, as little information is available on their application in agricultural crops.