Silicon increased the growth, productivity, and nutraceutical quality of tomato (Solanum lycopersicum L.)

Tomato (Solanum lycopersicum L.) is considered one of the most important horticultural crops worldwide due to its nutritional and organoleptic properties. Instead of chemical fertilizers, recent research has shown in several plant species the importance of silicon fertilization. Hence, the present investigation aims to evaluate the effect of three different doses (low, medium, and high dose) of silicon on the growth (stem length and diameter, root length diameter, and stem, leaf and root biomass), productivity (polar and equatorial fruit diameter, number of fruits per bunch and plant, and yield), and nutraceutical quality (total soluble solids, titratable acids, and vitamin C) parameters of tomato. The Si treatment affected the evaluated parameters in a dose dependent way in almost all the parameters evaluated. Despite the tomato is classified as a non-Si accumulator, it has a significant response to Si treatment at a low dose of 0.15 g plant-1, medium dose of 0.25 g plant-1, and high dose of 0.35 g plant-1 after 120 d of transplantation in terms of plant growth, yield, and quality parameters. The effectiveness of Si nutrition is dependent on factors such as element source, plant species, and cultivar, and even, the absorption and bioaccumulation capacity of this element could be different between varieties

Marine actinomycetes for biocontrol of Fusarium solani in tomato plants: In vitro and in vivo studies

Using microorganisms as biocontrol agents of phytopathogens has been an alternative to synthetic fungicides. Actinomycetes isolated from soil and plants have reduced diseases caused by phytopathogens; however, microorganisms from marine environments may be an option as biocontrol agents. The tomato crop possesses an important economic impact worldwide, being Mexico the main exporter. Several species of Fusarium cause damage to tomato crops and are controlled with synthetic fungicides. The objective of this work was to determine the effect of marine actinomycetes as biocontrol on Fusarium solani in tomato plants. Four strains of marine actinomycetes (A20, A19, A18, and A15) and one terrestrial actinomycete (ED48) were used. The actinomycetes strains used, produced siderophores. The greatest inhibition of mycelial growth of F. solani due to iron competition was obtained by strain A19 with 74.28%. Only two actinomycetes showed antifungal activity by VOCs (A19 and A18), strain A19 showed the highest antagonistic activity with PICR of 76.75%. Actinomycetes treatments showed significant differences with synthetic fungicide application in growth, disease severity (SE), and disease incidence (DI) variables. The application of marine actinomycete (A19) on plants infested with F. solani increased the levels of enzyme activity (SOD, POD, CAT, and PAL) versus plants in that only F. solani and distilled water (control) were applied. Actinomycetes of marine origin are an option as biocontrol agents for F. solani

Copper oxide nanoparticles biosynthetized improve germination and bioactive compounds in wheat sprouts

Metal nanoparticles have many positive effects in improving crop production and productivity and allow for increased germination and rapid crop establishment under field conditions. The metallic nanoparticles applied in this study were copper oxide nanoparticles (CuONPs) biosynthesized using orange peel (Citrus X sinensis) as a reducing agent to avoid or reduce toxicity in wheat seeds and sprouts. This study determined the effect of CuONPs on germination, radicle and plumule length, as well as the production of phytochemical compounds in wheat sprouts. The seeds were treated with suspensions of CuONPs at the following concentrations: 0, 0.5, 1, 2, 4 and 6 mg mL-1. The results indicate that the use of low doses of CuONPs (0.5 mg mL-1), improved germination, vigor, plumule and radicle length, in addition to increasing the biosynthesis of phytochemical compounds in wheat shoots. A high concentration of CuONPs (6 mg mL-1) causes inhibitory effects due to Cu accumulation and phytotoxicity in plant tissue. The use of CuONPs for green synthesis is a viable alternative to obtain beneficial effects in germination and seedling development, as well as greater secondary metabolite production

Effect of Pectimorf on the rooting ability, and morpho-physiological trials of national cocoa (Theobroma cacao L.) under different substrates

Cocoa is an economical cash crop that is formerly planted worldwide. Cuttings are a method of vegetative propagation suitable for maintaining desirable characteristics in cocoa trees. A greenhouse experiment was performed to evaluate the optimal concentrations of Pectimorf® (0, 10, 50, and 100 mg L-1) for rooting ability and seedling establishment as well as some physiological trials of 4 months EETP-800 national cocoa cuttings grown under two different substrates (S1: 80% soil + 20% sand and S2: 70% soil + 20% sand + 10% rice husk). The data showed that in most cases there are no significant differences in vegetative growth and root characteristics as well as gas exchange parameters between the two substrates. On the other hand, the application of Pectimorf® concentration enhanced all tested traits compared to untreated plants. The most effective in this regard was 100 mg L-1, that giving the highest value of all trials. As for the interaction effect, the result also shows that the application of Pectimorf® concentration in special at 100 mg L-1 among two substrates had an additive effect on plant growth, gas exchange, and survival percentage compared to non-treated cuttings. The application of 100 mg L-1 Pectimorf® with S2 substrate produced stronger seedlings with a higher survival percentage. This protocol can be used commercially for cocoa propagation commercially

A biopolymer with antimicrobial properties and plant resistance inducer against phytopathogens: Chitosan

Some synthetic fungicides have been currently prohibited due to their adverse effects; thus, searching for alternatives to decrease their application is a priority worldwide. An alternative to the application of synthetic fungicides is chitosan -a natural biopolymer- because of its biocompatibility, biodegradability, and bioactivity. Chitosan has been used in different industries, such as cosmetology, pharmaceutics, food, among others. In agriculture, it has been used as a resistance inductor and bio-fungicide because of its antimicrobial activity and for plant development as growth promoter. Although many works have been published on chitosan for its characteristics and mode of action, the direct effects on agriculture -both in plant and fruit phytopathogens- have not been reported. Therefore, the objective of this review is to summarize recent advances and achievements of chitosan application in agriculture with special attention to its antimicrobial properties and plant defence induction mechanisms

Morpho-physiology and Pht1 gene expressions in native maize plants with AM fungi and phosphorus

Maize is a crop important worldwide, but its production is limited to phosphorus availability in soil. Plants form a symbiotic association to improve their nutrition with arbuscular mycorrhizal fungi (AMF), which increase to absorption phosphorus (P) and the expression of transporters of the family Pht1. Few studies have focused on native maize plants and AMF. Thus, the objective of this study was to determine the morpho-physiological response and expression of phosphate Pht1 transporters in two native maize plants inoculated with Claroideoglomus etunicatum and P concentrations. The height, leaf area, dry biomass, CO2 assimilation rate, stomatal conductance, transpiration rate, intercellular CO2, water potential, greenness index, total chlorophyll, and ZEAma; Pht1;3 and ZEAma; Pht1;6 transporter expressions in maize plants under P (0.01 and 1 mM) concentrations were evaluated. The results showed that each native maize plant had a differential response in morpho-physiology and transporter expressions when they were inoculated with AMF and P. The response of maize plant was related with its genotype and phenotype plus environmental factor that influenced the AMF-host interaction, mycorrhizal colonization and soil nutrient absorption

Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

: The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

Effect of Marine Bacteria and Ulvan on the Activity of Antioxidant Defense Enzymes and the Bio-Protection of Papaya Fruit against Colletotrichum gloeosporioides

Anthracnose, caused by Colletotrichum gloeosporioides, is one of the most important diseases in papaya fruit. Its control has been achieved with synthetic fungicides, but the application of marine bacteria and the sulphated polysaccharide ulvan (structural description: β[1,4]-D-GlcA-α[1,4]-L-Rha 3 sulfate, β[1,4]-L-IdoA-α[1,4]-L-Rha 3 sulfate, β[1,4]-D-Xyl-α[1,4]-L-Rha 3 sulfate, and β[1,4]-D-Xyl 2-sulfate-α[1,4]-L-Rha 3 sulfate) from Ulva sp. can be an alternative in the use of agrochemicals. Thus, the objective of this study was to assess the effect in vitro and in vivo of two marine bacteria, Stenotrophomonas rhizophila and Bacillus amyloliquefaciens, and ulvan in papaya fruit’s bio-protection against C. gloeosporioides. The capacity of marine bacteria to inhibit mycelial growth and phytopathogen spore germination in vitro through volatile organic compounds (VOCs) and carbohydrate competition was evaluated. Fruit was inoculated with bacteria, ulvan, and C. gloeosporioides and incubated at 25 °C and 90% of relative humidity (RH) for seven days. Disease incidence (%), lesion diameter (mm), and antioxidant defense enzyme activity (such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were quantified. In vitro, C. gloeosporioides was inhibited by S. rhizophila and B. amyloliquefaciens. In vivo, disease incidence and the lesion diameter of anthracnose on papaya fruit were significantly reduced by marine bacteria and ulvan. Antioxidant defense enzyme activity played an important role in fruit bio-protection against C. gloeosporioides. The application of marine bacteria and ulvan can be an alternative in the sustainable postharvest management of papaya

Biocontrol of Postharvest Fruit Fungal Diseases by Bacterial Antagonists: A Review

This review deals with the main mechanisms of action exerted by antagonistic bacteria, such as competition for space and nutrients, suppression via siderophores, hydrolytic enzymes, antibiosis, biofilm formation, and induction of plant resistance. These mechanisms inhibit phytopathogen growth that affects postharvest fruit since quality and safety parameters are influenced by the action of these microorganisms, which cause production losses in more than 50% of fruit tree species. The use of synthetic fungicide products has been the dominant control strategy for diseases caused by fungi. However, their excessive and inappropriate use in intensive agriculture has brought about problems that have led to environmental contamination, considerable residues in agricultural products, and phytopathogen resistance. Thus, there is a need to generate alternatives that are safe, ecological, and economically viable to face this problem. Phytopathogen inhibition in fruit utilizing antagonist microorganisms has been recognized as a type of biological control (BC), which could represent a viable and environmentally safe alternative to synthetic fungicides. Despite the ecological benefit that derives from the use of controllers and biological control agents (BCA) at a commercial level, their application and efficient use has been minimal at a global level

Actinomycete Potential as Biocontrol Agent of Phytopathogenic Fungi: Mechanisms, Source, and Applications

Synthetic fungicides have been the main control of phytopathogenic fungi. However, they cause harm to humans, animals, and the environment, as well as generating resistance in phytopathogenic fungi. In the last few decades, the use of microorganisms as biocontrol agents of phytopathogenic fungi has been an alternative to synthetic fungicide application. Actinomycetes isolated from terrestrial, marine, wetland, saline, and endophyte environments have been used for phytopathogenic fungus biocontrol. At present, there is a need for searching new secondary compounds and metabolites of different isolation sources of actinomycetes; however, little information is available on those isolated from other environments as biocontrol agents in agriculture. Therefore, the objective of this review is to compare the antifungal activity and the main mechanisms of action in actinomycetes isolated from different environments and to describe recent achievements of their application in agriculture. Although actinomycetes have potential as biocontrol agents of phytopathogenic fungi, few studies of actinomycetes are available of those from marine, saline, and wetland environments, which have equal or greater potential as biocontrol agents than isolates of actinomycetes from terrestrial environments