Impact of the foliar application of potassium nanofertilizer on biomass, yield, nitrogen assimilation and photosynthetic activity in green beans

The agricultural areas of the world face problems that create difficulties when producing food and the excessive use of fertilizers is generating a negative environmental impact. An alternative that appears as a solution to this problem is the use of nanofertilizers. Within nanofertilizers an area of opportunity is the application of macronutrients, which report an increase in absorption efficiency of 19% compared to conventional fertilizers. Potassium (K) is one of the three macronutrients most used in agriculture and its deficiency affects key processes in plant development, limiting crop production. However, the number of publications where K is used as a nanofertilizer is limited, despite this, products in this form are already on the market. Therefore, the aim of this research work was to study the effect of the foliar application of K nanofertilizer on biomass, yield, nitrogen assimilation and photosynthetic activity in green beans cv. ‘Strike’. K was applied in the form of a nanofertilizer in doses of 0, 50, 100 and 200 ppm. The biomass accumulation, yield, nitrate reductase enzyme activity, photosynthetic activity and photosynthetic pigments were evaluated. The dose of 100 ppm of K nanofertilizer obtained a higher accumulation of biomass, nitrate reductase activity, photosynthetic activity, SPAD values and total chlorophyll content. While the 200-ppm dose obtained a higher increase in yield. The results obtained suggest that the application of K nanofertilizers benefits the physiological development of plants. However, more studies are required to compare the application of nanofertilizers with traditional fertilizers

Impact of the foliar application of nanoparticles, sulfate and iron chelate on the growth, yield and nitrogen assimilation in green beans

Nano-fertilizers (Nfs) have the potential to revolutionize agricultural systems through nanostructures ranging from 1 to 100 nm that address environmental responses and a more targeted biological demand. The purpose of this work was to study the impact of the foliar application of nanoparticles (NPs), sulfate and iron chelate on the growth, yield and assimilation of nitrogen in green beans. The iron was applied foliar in three different ways: Iron oxide nanoparticles (Fe2O3), ferric sulfate (Fe2(SO4)3) and iron chelate (Fe-EDDHA) in doses of 0, 25, 50, 100 and 200 ppm. The treatments that produced a higher total biomass increase were NPs and Fe-EDDHA at 50 ppm, with increases of 37% and 47% respectively compared to the control (with no application of Fe). Regarding the in vivo nitrate reductase activity, significant differences were obtained, particularly in the NPs and Fe-EDDHA treatment, with increases of 71% and 72% respectively. NPs at low doses favored maximum fruit production with increases of 88% in comparison to the control. Finally, it is concluded that the optimal doses that enhanced total biomass, production and assimilation of nitrogen were Fe2(SO4)3 at 25 ppm, Fe-EDDHA at 100 ppm and Fe2O3 at 25 ppm. The efficiency of foliar absorption of iron was found in treatments with Fe2O3 at 50 and 100 ppm. The foliar absorption efficiency of NPs offers sustainable alternatives to increase the productivity of the green bean

Biofortification potential in common bean (Phaseolus vulgaris L.): bioactive compounds, antioxidant capacity and physicochemical properties of 155 varieties grown in México

Common bean has been classified as an almost perfect food due to its high content of fiber, protein and bioactive compounds and its high antioxidant capacity, which has been attributed to having prevent diabetes, oxidative stress, bowel inflammation and cardiovascular diseases. The objective of this research work was to characterize the physicochemical properties and bioactive compounds of 155 varieties of common bean (Phaseolus vulgaris L.) produced in Mexico with potential to be biofortified. The contents of protein, fiber, fat, carbohydrates and energy were analyzed by the methods established by the AOAC, in addition the antioxidant capacity (DPPH), the content of total phenols, flavonoids, anthocyanins and phytic acid were obtained. Cluster, correlation, and principal component analysis were conducted. A total of 14 outstanding varieties was identified, where four varieties stood out about phenol and flavonoid content. A second group comprised by 10 varieties had high protein and anthocyanin levels and showed the second highest content of phenols and flavonoids. The diversity of beans obtained in outstanding varieties provides options for biofortification programs based on the consumption or place of origin of each variety

ZnO nanoparticles improve bioactive compounds, enzymatic activity and zinc concentration in grapevine

The low availability of micronutrients in the soil leads to a deficit of these micronutrients in crops, causing malnutrition in the population. Approximately 3,000 million people in the world have health problems caused by inadequate Zn intake. Agronomic biofortification is a way to produce crops rich in micronutrients and mitigate malnutrition problems. Nano biofortification with zinc oxide nanoparticles (NPs-ZnO) is a good strategy to mitigate and increase the nutritional content of the edible part of the plant. The aim was to determine the effect of foliar spraying with NPs-ZnO on yield and biosynthesis of enzymatic and non-enzymatic antioxidant compounds and their bioaccumulation. In this study, the effect of foliar fertilization with NPs-ZnO: 0, 25, 50, 75, and 100 mg L-1, on yield, the content of bioactive compounds and their bioaccumulation in grapevine berries was evaluated. The distribution of the treatments was under a completely randomized design, each treatment consisted of 10 plants, each representing one experimental unit. The treatments were applied by foliar sprays at fruit formation, in veraison and 15 days before harvest. Foliar spraying with NPs-ZnO positively modifies yield, the content of bioactive compounds, and their bioaccumulation. Doses of 50-75 mg L-1 of NPs-ZnO increased crop yield, and oenological parameters. In addition, all doses evaluated modified enzymatic and non-enzymatic antioxidants, and improving Zn concentration in grapevine berries. Foliar spraying of NPs-ZnO is an alternative to improve grape quality and yield, in addition to enriching its nutritional and antioxidant content

Biocontrol of the root-knot nematode Meloidogyne incognita with Purporeocillum lilacinum and liquid bio-formulates in tomato (Solanum lycopersicum)

Root-knot nematodes (Meloidogyne spp.) cause great losses in tomato crops. An environmentally friendly for its control is the use of predatory fungi such as Purporeocillum lilacinum, which reduces its population in the soil and mitigates yield losses. Therefore, the objective of the present study was to evaluate the biocontrol efficacy of the strains of the nematophagous fungus Purporeocillum lilacinum and liquid bioformulates on the eggs of the root-knot nematode Meloidogyne incognita, and the formation of galls on the tomato root. Two native strains of Purporeocillum lilacinum H2 and H3 combined with the bioformulated Extract of Beneficial Microorganisms (EPMB®) and the root exudate stimulator Exu-Root® were tested on Meloidogyne incognita eggs and tomato plants. The results obtained indicate that the Purporeocillum lilacinum H2 and H3 strains infected the Meloidogyne incognita eggs, interrupted the development of the embryos and caused their death, which significantly reduced the presence of galls in the root of the plants. In short, the maximum biological performance was presented with the treatments H2+Exu-Root® and H3+EPMB®, which had the lowest number of galls with 19.2 and 20.3 galls per plant respectively, compared to the control that presented 88 galls in the root and the treatments where the fungus was not applied (69-85 galls). Finally, it is concluded that the results demonstrate the potential of the Purporeocillum lilacinum H2 and H3 strains as biocontrol agents against the root-knot nematode Meloidogyne incognita, and that, in combination with EPMB® and Exu-Root®, the efficacy can be increased to reduce its population

Efficacy of the application of boron nanofertilizer on biomass, yield, nitrogen assimilation and photosynthetic activity in green beans

Boron (B) nanofertilizers are an innovative alternative with great potential to make nutrient application more efficient and thereby improve crop growth and productivity. However, nowadays there is little literature on the effects of boron nanofertilizers on physiological and biochemical processes in plants. Therefore, the objective of the present research was to study the efficacy of foliar application of a boron nanofertilizer on biomass, yield, nitrogen assimilation and photosynthetic activity in green beans plants cv. Strike. The B nanofertilizer was foliar applied at 0, 25, 50 and 100 ppm. Biomass accumulation, yield, nitrate reductase enzyme activity, photosynthetic activity, stomatal conductance and photosynthetic pigment content were evaluated. The results obtained indicate that the application of B nanofertilizer at dose of 25 ppm were more effective in improving biomass, while the dose of 100 ppm favoured nitrate reductase activity and stomatal conductance. The results suggest that the application of B nanofertilizers stimulated the development of green bean plants. Finally, more studies are needed to evaluate the possible phytotoxic effects of high doses of B nanofertilizers and to compare their effects with conventional B fertilizers already used in the market

Impact of the foliar application of magnesium nanofertilizer on physiological and biochemical parameters and yield in green beans

One of the most significant challenges humanity will face is food production. In order to preserve the output, mineral fertilizers are essential. However, it's not a suitable option in the long term. Magnesium is a crucial macronutrient, but it is the most limiting element in agriculture. Nanotechnology, with the implementation of nanofertilizers, is an excellent alternative since it provides nutrients, supports growth, and improves production; this in low amounts is more sustainable than conventional fertilizers. Although there is a piece of limited information regarding the proper foliar application of this macronutrient, the study helped to validate the effect of the foliar application of Magnesium nano fertilizer on the physiological, biochemical responses and yield of bean plants. Bean plants ejotero cv. ‘Strike’ and magnesium nanoparticles were applied at doses of 0, 50, 100, and 200 ppm. The biomass accumulation, yield, activity of the enzyme nitrate reductase, and photosynthetic pigments were evaluated. The foliar application of Mg nanoparticles at 50 ppm generated the highest amount of biomass and photosynthetic pigments. The 100 ppm dose improved pods yield and allowed the increased activity of the Nitrate Reductase enzyme. The results obtained suggest that, when increasing the dose of magnesium in plants, the amount of carotenes decreases

Inventario y descripción de las soluciones de accesibilidad a la web existentes para personas con discapacidad fisica y sensorial

El elemento más representativo de la nueva sociedad de la información lo constituye sin duda la World Wide Web. La Red, como es conocida popularmente, une a millones de ordenadores en todo el mundo, aportando una riqueza de información inimaginable hace pocos años y un interfaz de uso tan gráfico e intuitivo que ha significado una expansión permanente de su uso a millones de usuarios nuevos cada año. La accesibilidad Web se puede definir como la posibilidad de que un producto o servicio Web sea usado por el mayor número posible de personas, independientemente de las limitaciones del individuo o de las del contexto de uso. De acuerdo con el Tratado de Amsterdam de la Unión Europea, en aplicación de la cláusula de no-discriminación, las políticas europeas y la de los Estados miembros deberían inspirarse en el principio de no-discriminación con vistas a hacer realidad la igualdad para las personas con discapacidad. Este informe tiene como objetivo realizar un inventario de las soluciones, existentes en el mercado, tanto de software como de hardware para poder garantizar esa no discriminación de todas las personas

Influencia de la fertilización nitrogenada sobre las concentraciones de K+, Mg2+ y Ca2+ y sus bioindicadores en raíces y hojas de plantas de judía

The pyruvate kinase (PK) and ATPase activities taking part in nitrogen (N) assimilation is essential for the growth and development of plants. Studies on the kinetics of these enzymes reveal that its activities are dependent of the cofactors K+, Ca2+, and Mg2+. Therefore, the objective of the present work was to determine the effect of different doses of N on enzymatic activities of ATPase and PK as potentials biochemical indicators of the levels of K+, Mg2+, and Ca2+ in the roots and leaves of green bean plants. The N was applied to the nutrient solution as NH4NO3 at the following rates: 1.5, 3.0, 6.0, 12.0, 18.0, and 24.0 mM of N. These results indicate that deficient conditions of N (N1 and N2) were characterized by the lowest accumulation of K+, Mg2+ and Ca2+ in both total and soluble forms, and also minimum activities of PK and ATPase induced by K+, Mg2+ and Ca2+, with respect to the activity of basal PK and ATPase; this could mean near optimum conditions for these cations. On the contrary, high-N treatments (N4, N5 and N6) were characterized by presenting decreasing concentrations of total and soluble K+, Mg2+ and Ca2+ in roots and leaves of green bean plants; however, the activities of PK and ATPase induced with K+, Mg2+ and Ca2+ were increased reaching their maximum activity with respect to basal PK and ATPase, both enzymes reflecting the level of cations in roots and leaves, hence being considered as good physiological bioindicators of these cations.Las actividades piruvato kinasa (PK) y ATPasa participan en la asimilación de nitrógeno (N), la cual es esencial para el crecimiento y desarrollo de las plantas. Estudios sobre cinéticas de estas enzimas revelan que sus actividades son dependientes de los cofactores K+, Ca2+ y Mg2+. Por lo tanto, el objetivo del presente trabajo fue determinar el efecto de diferentes dosis de N sobre las actividades de la ATPasa y PK como posibles bioindicadores de los niveles de K+, Mg2+ y Ca2+ en raíces y hojas de plantas de judía (Phaseolus vulgaris L. cv. Strike). Se aplicó N a la solución nutritiva como NH4NO3 en las siguientes dosis: N1=1,5 mM, N2=3,0 mM, N3=6,0 mM, N4=12,0 mM, N5=18,0 mM y N6=24,0 mM. Los resultados indican que bajo condiciones deficientes de N (N1 y N2), las plantas presentaron menor acumulación de K+, Mg2+ y Ca2+ en su forma total y soluble, así como mínimas actividades PK y ATPasa inducidas por K+, Mg2+ y Ca2+ respecto a la actividad PK y ATPasa basal; lo cual indica condiciones cercanas a las óptimas de estos cationes. Por el contrario, en los tratamientos elevados de N (N4, N5 y N6) las plantas presentaron concentraciones decrecientes de K+, Mg2+ y Ca2+ total y soluble tanto en raíces como en hojas; sin embargo, las actividades PK y ATPasa inducidas con K+, Mg2+ y Ca2+ se incrementaron alcanzando sus máximas actividades con respecto a la PK y ATPasa basal, lo que indica una mayor necesidad fisiológica de estos cationes en los tratamientos elevados de N. Finalmente, la actividad ATPasa basal y la inducida con K+, Mg2+ y Ca2+ se comportaron de forma similar a la actividad PK, lo que refleja el nivel de cationes en raíces y en hojas, por lo que se consideran buenos bioindicadores fisiológicos de estos cationes

An Olive-Derived Extract 20% Rich in Hydroxytyrosol Prevents beta-Amyloid Aggregation and Oxidative Stress, Two Features of Alzheimer Disease, via SKN-1/NRF2 and HSP-16.2 in Caenorhabditis elegans

The authors gratefully acknowledge the funding support of FEDER/Junta de AndaluciaConsejeria de Economia y Conocimiento, Grant B-AGR-193-UGR18. Also grant PID2019-106778RBI00, funded by MCIN/AEI/10.13039/501100011033 FEDER "Una manera de hacer Europa".Olive milling produces olive oil and different by-products, all of them very rich in different bioactive compounds like the phenolic alcohol hydroxytyrosol. The aim of the present study was to investigate the effects of an olive fruit extract 20% rich in hydroxytyrosol on the molecular mechanisms associated with Alzheimer disease features like A beta- and tau- induced toxicity, as well as on oxidative stress in Caenorhabditis elegans. Moreover, characterization of the extracts, regarding the profile and content of phenolics, as well as total antioxidant ability, was investigated. The study of lethality, growth, pharyngeal pumping, and longevity in vivo demonstrated the lack of toxicity of the extract. One hundred mu g/mL of extract treatment revealed prevention of oxidative stress and a delay in A beta-induced paralysis related with a lower presence of A beta aggregates. Indeed, the extract showed the ability to avoid a certain degree of proteotoxicity associated with aggregation of the tau protein. According to RNAi tests, SKN-1/NRF2 transcription factor and the overexpression of HSP-16.2 were mechanistically associated in the observed effects.FEDER/Junta de AndaluciaConsejeria de Economia y Conocimiento B-AGR-193-UGR18 PID2019-106778RBI00 MCIN/AEI/10.13039/50110001103