Bacillus velezensis BE2 controls wheat and barley diseases by direct antagonism and induced systemic resistance

Wheat and barley rank among the main crops cultivated on a global scale, providing the essential nutritional foundation for both humans and animals. Nevertheless, these crops are vulnerable to several fungal diseases, such as Septoria tritici blotch and net blotch, which significantly reduce yields by adversely affecting leaves and grain quality. To mitigate the effect of these diseases, chemical fungicides have proven to be genuinely effective; however, they impose a serious environmental burden. Currently, biocontrol agents have attracted attention as a sustainable alternative to fungicides, offering an eco-friendly option. The study aimed to assess the efficacy of Bacillus velezensis BE2 in reducing disease symptoms caused by Zymoseptoria tritici and Pyrenophora teres. This bacterium exhibited significant antagonistic effects in vitro by suppressing fungal development when pathogens and the beneficial strain were in direct confrontation. These findings were subsequently confirmed through microscopic analysis, which illustrated the strain's capacity to inhibit spore germination and mycelial growth in both pathogens. Additionally, the study analysed the cell-free supernatant of the bacterium using UPLC-MS (ultra-performance liquid chromatography-mass spectrometry). The results revealed that strain BE2 produces, among other metabolites, different families of cyclic lipopeptides that may be involved in biocontrol. Furthermore, the beneficial effects of strain BE2 in planta were assessed by quantifying the fungal DNA content directly at the leaf level after bacterization, using two different application methods (foliar and drenching). The results indicated that applying the beneficial bacterium at the root level significantly reduced pathogens pressure. Finally, gene expression analysis of different markers showed that BE2 application induced a priming effect within the first hours after infection. KEY POINTS: • BE2 managed Z. tritici and P. teres by direct antagonism and induced systemic resistance. • Strain BE2 produced seven metabolite families, including three cyclic lipopeptides. • Application of strain BE2 at the root level triggered plant defense mechanisms.

Effects of synergistic modification using alkalis and guar gum on the pasting, rheological, and microstructural properties of germinated highland barley starch gels

Germination treatment of highland barley enhances its nutritional value while weakening the starch gel properties. This study aims to enhance the characteristics of germinated highland barley starch (GBS) by exploring the synergistic effects of two alkalis (Na2CO3 and NaHCO3) and guar gum (GG) on GBS gel properties. The combined action of alkalis and GG significantly improved the peak viscosity, setback viscosity, and hardness compared with GG alone. The highest G' and G" reached 998 and 204 Pa at 0.4% Na2CO3 addition, which were increased by nearly 44% and 50%, respectively. Fourier-transform infrared spectral analysis revealed that the alkalis strengthened interaction forces, particularly with intensified absorption peaks at 3200-3700 cm-1 and 1550-1750 cm-1. The Na2CO3 and NaHCO3 reduced the spin-spin relaxation time (T2), resulting in a dense starch gel network. This study contributes to enhancing the market application of GBS and offers innovative insights for modifying other starches.

The right banker plant for the right application: Comparison of three candidates for aphid biocontrol, barley (Hordeum vulgare L.), corn (Zea mays L.), and finger millet (Eleusine coracana (L.) Gaertn)

BACKGROUND

In temperate regions, aphid biological control in greenhouses is mostly achieved by the regular release of biocontrol agents. Due to the rapid growth rate of the aphid population, biocontrol agents must be released frequently in order to be present before pest outbreaks and to act rapidly to prevent exceeding the economic threshold. Banker plants reduce these numerous releases by providing natural enemies with a high-quality environment to develop and reproduce. Optimally, banker plants should be easy to produce, resistant to environmental conditions, provide a large amount of suitable banker prey in order to produce a high number of biocontrol agents, and resist the herbivory pressure of the banker prey. The present study aimed to compare the value of three banker plant candidates of the Poaceae family under laboratory and greenhouse conditions: barley (Hordeum vulgare L.), finger millet (Eleusine coracana (L.) Gaertn), and corn (Zea mays L.).

RESULTS

Our results show that the three plants were suitable for different contexts. Finger millet yielded the biggest fresh plant biomass, supported the highest load of banker prey, and resisted aphid feeding longer than the other plant species. Corn was the cheapest to produce, and barley was the fastest to grow.

CONCLUSIONS

Overall, finger millet could be more fitted for long crop cycles, pests with rapid population growth rates, and voracious or fast-reproducing biocontrol agents. Meanwhile, barley and corn may be better suited for rapid crop cycles, pests with slow population growth rates, and biocontrol agents that are not too voracious or have low reproductive rates. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Heterologous expression and enzymatic characteristics of sulfatase from Lactobacillus plantarum dy-1

Barley, rich in bioactive components including dietary fiber, polyphenolic compounds and functional proteins, exhibits health benefits such as regulating glucose and lipid metabolism. Previous studies have found that the content and composition of free phenolic acids in barley may be significantly changed by fermentation with the laboratory patented strain Lactobacillus plantarum dy-1 (L. p dy-1), but the mechanism of enzymatic release of phenolic acid remains to be elucidated. Based on this, this study aimed to identify the key enzyme in L. p dy-1 responsible for releasing the bound phenolic acid and to further analyze its enzymatic properties. The Carbohydrate-Active enZYmes database revealed that L. p dy-1 encodes 7 types of auxiliary enzymes, among which we have identified a membrane sulfatase. The enzyme gene LPMS05445 was heterologous to that expressed in E. coli, and a recombinant strain was induced to produce the target protein and purified. The molecular weight of the purified enzyme was about 59.9 kDa, with 578.21 U mg-1 enzyme activity. The optimal temperature and pH for LPMS05445 expression were 40 °C and 7.0, respectively. Furthermore, enzymatic hydrolysis by LPMS05445 can obviously change the surface microstructure of dietary fiber from barley bran and enhance the release of bound phenolic acid, thereby increasing the free phenolic acid content and improving its physiological function. In conclusion, sulfatase produced by Lactobacillus plantarum dy-1 plays a key role in releasing bound phenolic acids during the fermentation of barley.

Degradation and environmental assessment of compostable packaging mixed with biowaste in full-scale industrial composting conditions

The incorporation of representative commercial compostable materials into a full-scale open-air windrow composting process in an industrial site using household-separated biowaste was investigated. Two batches out of the same initial biowaste mixture were studied, one as control and the other containing initially 1.28 wt% of certified compostable plastics. No significant differences in the composting process were revealed. Compostable plastics exhibited a 98 wt% mass loss after 4 months, aligning with industrial composting times. The evolution of the morphology of the materials unveiled polymer specific degradation mechanisms. Both Safety requirements for organic farming were met. Ecotoxicity tests showed no adverse effects, agronomic fertilizing and amending quality was high, the materials compost even enhancing barley growth. The ecological impact assessment demonstrated an advantage for composting over incineration for seven of the eight indicators. In conclusion, this study shows the successful integration of compostable materials into industrial composting, upholding product safety and quality.

Pyricularia oryzae: Lab star and field scourge

Pyricularia oryzae (syn. Magnaporthe oryzae), is a filamentous ascomycete that causes a major disease called blast on cereal crops, as well as on a wide variety of wild and cultivated grasses. Blast diseases have a tremendous impact worldwide particularly on rice and on wheat, where the disease emerged in South America in the 1980s, before spreading to Asia and Africa. Its economic importance, coupled with its amenability to molecular and genetic manipulation, have inspired extensive research efforts aiming at understanding its biology and evolution. In the past 40 years, this plant-pathogenic fungus has emerged as a major model in molecular plant-microbe interactions. In this review, we focus on the clarification of the taxonomy and genetic structure of the species and its host range determinants. We also discuss recent molecular studies deciphering its lifecycle.

TAXONOMY

Kingdom: Fungi, phylum: Ascomycota, sub-phylum: Pezizomycotina, class: Sordariomycetes, order: Magnaporthales, family: Pyriculariaceae, genus: Pyricularia.

HOST RANGE

P. oryzae has the ability to infect a wide range of Poaceae. It is structured into different host-specialized lineages that are each associated with a few host plant genera. The fungus is best known to cause tremendous damage to rice crops, but it can also attack other economically important crops such as wheat, maize, barley, and finger millet.

DISEASE SYMPTOMS

P. oryzae can cause necrotic lesions or bleaching on all aerial parts of its host plants, including leaf blades, sheaths, and inflorescences (panicles, spikes, and seeds). Characteristic symptoms on leaves are diamond-shaped silver lesions that often have a brown margin and whose appearance is influenced by numerous factors such as the plant genotype and environmental conditions. USEFUL WEBSITES Resources URL Genomic data repositories http://genome.jouy.inra.fr/gemo/ Genomic data repositories http://openriceblast.org/ Genomic data repositories http://openwheatblast.net/ Genome browser for fungi (including P. oryzae) http://fungi.ensembl.org/index.html Comparative genomics database https://mycocosm.jgi.doe.gov/mycocosm/home T-DNA mutant database http://atmt.snu.kr/ T-DNA mutant database http://www.phi-base.org/ SNP and expression data https://fungidb.org/fungidb/app/.

Insights into the effect mechanism of acidic pH condition on the in vitro starch digestion of black highland barley semi-dried noodles

In this study, black highland barley semi-dried noodles (BHBSNs) were adjusted to acidic pH (5.0, 4.5, 4.0) with an acidity regulator (monosodium fumarate) for obtaining low glycemic index (GI) BHBSNs, and the changes in the in vitro starch digestion, free phenolic content, and α-amylase activity in BHBSNs were investigated. The estimated glycemic index (eGI) of BHBSNs decreased from 59.23 to 52.59, 53.89 and 53.61, respectively, as the pH was adjusted from 6.0 to 5.0, 4.5, 4.0. As the pH of BHBSNs decreased, the equilibrium hydrolysis (C∞) decreased, and kinetic coefficient (k) decreased and then increased. Compared to the control, the pH of the digestive fluid decreased during digestion with decreasing pH, and the α-amylase inhibition of BHBSNs with pH 5.0, 4.5, and 4.0 increased by 56.54 %, 75.18 %, and 107.98 %, respectively. In addition, as the pH of BHBSNs decreased, the free phenolic content and the content of released phenolics during digestion increased. Pearson correlations analysis showed that the increase in α-amylase inhibition and phenolic release during digestion induced by acidic pH was negatively correlated with the eGI and C∞ of BHBSNs. This study indicated that acidic pH condition could modulate starch digestion for preparing low GI BHBSNs.

Unravelling the combined impacts of drought and Cu in barley plants - double trouble?

The occurrence of drought in soils, particularly in those contaminated by metals, poses a current threat to crops, as these factors can interact and induce unique stress responses. Therefore, this study mainly focused on understanding the crosstalk between drought and copper (Cu) stress in the physiology of the barley (Hordeum vulgare L.) plant. Using a bifactorial experimental design, seedlings were grown in a natural soil under the following treatments: plants continuously irrigated in uncontaminated soil for 14 days (control); plants continuously irrigated in Cu-contaminated soil (115 mg Cu kg-1) for 14 days (Cu); plants only irrigated during the initials 7 days of growth in uncontaminated soil (drought); plants co-exposed to Cu and drought (combined). After 14 days of growth, the results revealed that drought prevented Cu bioaccumulation in barley roots, which were still severely affected by the metal, both individually and in combination with the water deficit. Furthermore, individual and combined exposure to these stressors resulted in impaired photosynthetic performance in barley plants. Despite the increased activation of enzymatic and non-enzymatic antioxidant defence mechanisms, particularly in the green organs, the plants co-exposed to both stress factors still showed higher oxidative damage, severely impacting biomass production.

Applications of humic and fulvic acid under saline soil conditions to improve growth and yield in barley

BACKGROUND

Enriching the soil with organic matter such as humic and fulvic acid to increase its content available nutrients, improves the chemical properties of the soil and increases plant growth as well as grain yield. In this study, we conducted a field experiment using humic acid (HA), fulvic acid (FA) and recommended dose (RDP) of phosphorus fertilizer to treat Hordeum vulgare seedling, in which four concentrations from HA, FA and RDP (0.0 %, 50 %, 75 % and 100%) under saline soil conditions . Moreover, some agronomic traits (e.g. grain yield, straw yield, spikes weight, plant height, spike length and spike weight) in barley seedling after treated with different concentrations from HA, FA and RDP were determined. As such the beneficial effects of these combinations to improve plant growth, N, P, and K uptake, grain yield, and its components under salinity stress were assessed.

RESULTS

The findings showed that the treatments HA + 100% RDP (T1), HA + 75% RDP (T2), FA + 100% RDP (T5), HA + 50% RDP (T3), and FA + 75% RDP (T6), improved number of spikes/plant, 1000-grain weight, grain yield/ha, harvest index, the amount of uptake of nitrogen (N), phosphorous (P) and potassium (K) in straw and grain. The increase for grain yield over the control was 64.69, 56.77, 49.83, 49.17, and 44.22% in the first season, and 64.08, 56.63, 49.19, 48.87, and 43.69% in the second season,. Meanwhile, the increase for grain yield when compared to the recommended dose was 22.30, 16.42, 11.27, 10.78, and 7.11% in the first season, and 22.17, 16.63, 11.08, 10.84, and 6.99% in the second season. Therefore, under salinity conditions the best results were obtained when, in addition to phosphate fertilizer, the soil was treated with humic acid or foliar application the plants with fulvic acid under one of the following treatments: HA + 100% RDP (T1), HA + 75% RDP (T2), FA + 100% RDP (T5), HA + 50% RDP (T3), and FA + 75% RDP (T6).

CONCLUSIONS

The result of the use of organic amendments was an increase in the tolerance of barley plant to salinity stress, which was evident from the improvement in the different traits that occurred after the treatment using treatments that included organic amendments (humic acid or fulvic acid).

Evaluation of Gluten Protein Profiles in Hydrolyzed Food Products by a Multiplex-Competitive Enzyme-Linked Immunosorbent Assay

The apparent gluten concentration profiles of 47 hydrolyzed foods (barley malt, sprouted grains, and hydrolyzed wheat proteins (HWP)) were evaluated using a multiplex-competitive ELISA that utilizes the G12, R5, 2D4, MIoBS, and Skerritt antibodies from commercial sources. Cluster analysis was conducted to evaluate similarities or differences in the gluten protein/peptide response profiles among the hydrolyzed foods and their similarities or differences with fermented foods analyzed previously by the ELISA. The gluten protein/peptide response profiles of the hydrolyzed foods mainly depended on the grain source (wheat, rye, or barley) of gluten. Some hydrolyzed foods presented profiles similar to those of certain fermented foods (e.g., barley malt and gluten reduced barley beers), whereas others presented unique profiles (e.g., HWP and sprouted wheat). Additional analysis using wheat gluten-incurred yogurts indicated that while not suitable for the barley- or rye-containing foods tested, a newly developed gluten-incurred yogurt calibrant shows promise for the possible use in the quantitation of several wheat-containing fermented and hydrolyzed foods.

Bacillus velezensis RC218 and emerging biocontrol agents against Fusarium graminearum and Fusarium poae in barley: in vitro, greenhouse and field conditions

Fusarium head blight (FHB) is one of the most common diseases in Argentina, affecting the quality and yield of barley grains. Fusarium graminearum sensu stricto (ss) and Fusarium poae are causal agents of FHB and potential sources of mycotoxin contamination in barley. Conventional management strategies do not lead to a complete control of FHB; therefore, biological control emerges as an eco-friendly alternative in the integrated management of the disease. In the present work, Bacillus velezensis, Bacillus inaquosorum, Bacillus nakamurai and Lactobacillus plantarum were evaluated as potential biocontrol agents against F. graminearum ss and F. poae on barley-based media. Bacillus velezensis RC218 was selected to carry out greenhouse and field trials in order to reduce FHB and mycotoxin accumulation. This strain was able to control growth of both Fusarium species and reduced deoxynivalenol (DON) and nivalenol (NIV) production by 66 % and 79 %, respectively. Bacillus inaquosorum and B. nakamurai were more effective in controlling F. poae growth, and the mean levels of reduction in DON accumulation were 50 and 38 %, and 93 and 26 % for NIV, respectively. Lactobacillus plantarum showed variable biocontrol capacity depending on the strain, with no significant mycotoxin reduction. The biocontrol on incidence and severity of FHB in the greenhouse and field trials was effective, being more efficient against F. graminearum ss and DON accumulation than against F. poae and NIV occurrence. This study provides valuable data for the development of an efficient tool based on biocontrol agents to prevent FHB-producing Fusarium species development and mycotoxin occurrence in barley, contributing to food safety.

Isolation and identification of a new Bacillus glycinifermentans strain from date palm rhizosphere and its effect on barley seeds under heavy metal stress

Soil contamination by heavy metals is one of the major problems that adversely decrease plant growth and biomass production. Inoculation with the plant growth-promoting rhizobacteria (PGPR) can attenuate the toxicity of heavy metals and enhancing the plant growth. In this study, we evaluated the potential of a novel extremotolerant strain (IS-2 T) isolated from date palm rhizosphere to improve barley seedling growth under heavy metal stress. The species-level identification was carried out using morphological and biochemical methods combined with whole genome sequencing. The bacterial strain was then used in vitro for inoculating Hordeum vulgare L. exposed to three different Cr, Zn, and Ni concentrations (0.5, 1, and 2 mM) in petri dishes and different morphological parameters were assessed. The strain was identified as Bacillus glycinifermentans species. This strain showed high tolerance to pH (6-11), salt stress (0.2-2 M), and heavy metals. Indeed, the minimum inhibitory concentrations at which bacterium was unable to grow were 4 mM for nickel, 3 mM for zinc, more than 8 mM for copper, and 40 mM for chromium, respectively. It was observed that inoculation of Hordeum vulgare L. under metal stress conditions with Bacillus glycinifermentans IS-2 T stain improved considerably the growth parameters. The capacity of the IS-2 T strain to withstand a range of abiotic stresses and improve barley seedling development under lab conditions makes it a promising candidate for use as a PGPR in zinc, nickel, copper, and chromium bioremediation.

Beneficial glycaemic effects of high-amylose barley bread compared to wheat bread in type 2 diabetes

BACKGROUND

Cereals foods with a high content of dietary fibres or amylose have potential to lower postprandial glucose levels. Optimisation of cereal foods may improve management of type 2 diabetes (T2D).

METHODS

We investigated the impact on 4 h postprandial glucose responses given as incremental area under curve (iAUC) of bread made of either 50% RNAi-based (genetically modified) amylose-only barley flour (AmOn) (and 50% wheat flour), 50% hulless barley flour (and 50% wheat flour) or 75% hulless barley (and 25% wheat flour) in subjects with T2D compared with 100% wheat flour bread.

DESIGN

Twenty adults with T2D were randomly allocated to one of four breads at four separate visits. We measured fasting and 4 h postprandial responses of glucose, insulin, glucagon, triacylglycerol (TG), free fatty acids (FFA), glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP). Mixed model ANOVA was used to examine the differences.

RESULTS

Bread made from 50% AmOn lowered the 4 h postprandial glucose by 34%, 27%, 23% (P < 0.05) compared with 100% wheat, 50% or 75% hulless barley, respectively. Bread made from 75% hulless barley reduced the postprandial glucose response (iAUC) by 11% (P < 0.05) compared to 100% wheat bread. Postprandial insulin responses (iAUC) were reduced for 50% AmOn compared with 100% wheat and 50% hulless barley and for 75% hulless compared to 50% hulless barley bread (P < 0.05). 4 h postprandial glucagon (tAUC) did not differ between the four bread types (P > 0.05). Lower postprandial GIP (iAUC) was observed after all barley breads compared to 100% wheat (P < 0.05), whereas no difference was seen in postprandial GLP-1. Postprandial TG and FFA (tAUC) were difficult to judge due to differences in fasting values.

CONCLUSIONS

Bread made by replacing wheat flour with either 50% high-amylose or 75% hulless barley flour lowered postprandial glucose responses compared to 100% wheat bread indicating a beneficial impact on glucose regulation in T2D subjects. This trial was registered at clinicaltrials.gov as NCT04646746.

Insoluble fibre and enzyme supplementation in mash or pellets diets on growth performance, apparent ileal digestibility and intestinal morphology of broiler chickens fed barley containing diets

BACKGROUND

Enzyme supplementation and the inclusion of fibre in the barley-based diets have been some of the alternatives proposed to improve productivity in the absence of growth promoters.

OBJECTIVE

This study was performed to investigate the effect of adding sunflower hulls (SFH), a multi-enzyme carbohydrate, and feed forms (mash and pellet) on performance and some physiological parameters in broiler chickens fed barley containing diets.

METHODS

Treatments were two feed forms (mash vs. pelleted), and four diets consisted of a barley-based diet (control, CTL) or test diets which contained either SFH at 30 g/kg, enzyme (ENZ; 0.2 g/kg) or combination of SFH and enzyme (SFH + ENZ).

RESULTS

The results showed that average daily feed intake and average daily gain were significantly increased in chickens that were fed ENZ (p < 0.05). The highest digestibility of ether extract (EE) was observed in the treatment containing SFH and SFH + ENZ (p < 0.05). The highest population of Lactobacillus spp. was observed in the treatment containing SFH (p < 0.05). The villus height and villus height to crypt depth ratios of duodenum and jejunum were significantly higher (p < 0.05) in broilers fed pellet diets compared to the mash.

CONCLUSION

It can be concluded that pellet diets reduce digesta viscosity and harmful microorganisms (Escherichia coli), increase growth performance, and improve intestinal morphology in barley-based diets. Moreover, SFH and ENZ had favourable effects on EE digestibility and caecal microbial population of broilers fed with barley containing diets.

Antipyretic activity of the hydro-alcoholic extract of Artemisia absinthium L. as a standalone and as an adjuvant with barley water against yeast-induced pyrexia in albino Wistar rats

OBJECTIVES

In Unani medicine, a comprehensive treatment plan has been delineated to deal with febrile illnesses using herbal drugs along with modified dietetics, which stands as a promising area of research. The present study was aimed at evaluating the antipyretic activity of the HAE of Artemisia absinthium L. whole plant as a standalone and as an adjuvant with barley water in an animal model of pyrexia to validate the age-old Unani principle of the treatment.

METHODS

The pyrexia was induced in all the groups except the plain control using Brewer's yeast. Group II did not receive any treatment, while group III received crocin, group IV received HAE of A. absinthium, group V administered Ma al-Sha'ir, and group VI was treated with the HAE of A. absinthium along with Ma al-Sha'ir by oral route. The rectal temperature of each rat was recorded at '0' h, 30 min, 60 min, and 180 min.

RESULTS

The mean rectal temperature of group III went down from 101.82±0.20 °F to 100.4±0.57 °F over the period of (0-180) minutes, whereas the mean temperature in group IV went down from 102.45±0.60 °F to 100.14±0.57 °F. The mean rectal temperature of group V decreased from 100.62±0.11 °F to 99.55±0.51 °F, while the mean rectal temperature of group VI went down from 101.95±0.1 °F to 97.7±0.11 °F.

CONCLUSIONS

It is concluded that the HAE of A. absinthium L. as a standalone and along with Ma al Sha'ir showed excellent antipyretic activity as compared to the standard drug in an animal model.

Improving productivity and soil fertility in Medicago sativa and Hordeum marinum through intercropping under saline conditions

BACKGROUND AND AIMS

Intercropping is an agriculture system used to enhance the efficiency of resource utilization and maximize crop yield grown under environmental stress such as salinity. Nevertheless, the impact of intercropping forage legumes with annual cereals on soil salinity remains unexplored. This research aimed to propose an intercropping system with alfalfa (Medicago sativa)/sea barley (Hordeum marinum) to explore its potential effects on plant productivity, nutrient uptake, and soil salinity.

METHODS

The experiment involved three harvests of alfalfa and Hordeum marinum conducted under three cropping systems (sole, mixed, parallel) and subjected to salinity treatments (0 and 150 mM NaCl). Agronomical traits, nutrient uptake, and soil properties were analyzed.

RESULTS

revealed that the variation in the measured traits in both species was influenced by the cultivation mode, treatment, and the interaction between cultivation mode and treatment. The cultivation had the most significant impact. Moreover, the mixed culture (MC) significantly enhanced the H. marinum and M. sativa productivity increasing biomass yield and development growth under salinity compared to other systems, especially at the second harvest. Furthermore, both intercropping systems alleviated the nutrient uptake under salt stress, as noted by the highest levels of K+/Na+ and Ca2+/Mg2+ ratios compared to monoculture. However, the intercropping mode reduced the pH and the electroconductivity (CEC) of the salt soil and increased the percentage of organic matter and the total carbon mostly with the MC system.

CONCLUSIONS

Intercropped alfalfa and sea barely could mitigate the soil salinity, improve their yield productivity, and enhance nutrient uptake. Based on these findings, we suggest implementing the mixed-culture system for both target crops in arid and semi-arid regions, which further promotes sustainable agricultural practices.

Do Growers Using Solo Fungicides Affect the Durability of Disease Control of Growers Using Mixtures and Alternations? The Case of Spot-Form Net Blotch in Western Australia

Growers often use alternations or mixtures of fungicides to slow down the development of resistance to fungicides. However, within a landscape, some growers will implement such resistance management methods, whereas others do not, and may even apply solo components of the resistance management program. We investigated whether growers using solo components of resistant management programs affect the durability of disease control in fields of those who implement fungicide resistance management. We developed a spatially implicit semidiscrete epidemiological model for the development of fungicide resistance. The model simulates the development of epidemics of spot-form net blotch disease, caused by the pathogen Pyrenophora teres f. maculata. The landscape comprises three types of fields, grouped according to their treatment program, with spore dispersal between fields early in the cropping season. In one field type, a fungicide resistance management method is implemented, whereas in the two others, it is not, with one of these field types using a component of the fungicide resistance management program. The output of the model suggests that the use of component fungicides does affect the durability of disease control for growers using resistance management programs. The magnitude of the effect depends on the characteristics of the pathosystem, the degree of inoculum mixing between fields, and the resistance management program being used. Additionally, although increasing the amount of the solo component in the landscape generally decreases the lifespan within which the resistance management program provides effective control, situations exist where the lifespan may be minimized at intermediate levels of the solo component fungicide. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

Characterization and correlation of the probing behaviors of Macrosteles quadrilineatus (Hemiptera: Cicadellidae) with electropenetrography (EPG) waveforms

Aster leafhopper (Hemiptera: Cicadellidae: Macrosteles quadrilineatus Forbes) is a polyphagous insect species that migrates into the upper Midwest of the United States and the Western Canadian Prairies. Populations of this insect are associated with the transmission of a plant pathogen (Candidatus Phytoplasma asteris, 16SrI) to several annual crops and perennial plant species. Previous studies suggest that aster leafhoppers can sometimes prefer less suitable hosts for their development and survival, yet it is unclear if this lower performance on certain plant species is associated with reduced or impaired probing behaviors due to characteristics of the plants. To characterize the probing behaviors of aster leafhoppers, direct current electropenetrography recordings of male and female adults on barley (Polaes: Poaceae: Hordeum vulgare L.) were combined with plant histology, allowing the identification of nine waveforms and their proposed biological meanings. For each waveform, the number of waveform events per insect (NWEI), the waveform duration per insect (WDI), the waveform duration per event per insect (WDEI), and the percentage of recording time were calculated and statistically compared between sexes. Male and female aster leafhoppers exhibited similar behavioral responses for most of these variables, except for the NWEI for waveforms associated with nonprobing activities and the pathway phase. In these cases, male aster leafhoppers exhibited a higher number of events than females. Comparison of the proposed waveforms in this study with previous work on other hemipteran species provided additional support to the interpretation of the biological activities associated with each waveform.

Effects of high-pressure microfluidization treatment on the structural, physiochemical properties of insoluble dietary fiber in highland barley bran

High-pressure microfluidization treatment (HPMT) was performed on the insoluble dietary fiber (IDF) of highland barley bran (HBB), with conditions set at 60 MPa (IDF-60), 120 MPa (IDF-120), and two consecutive high-pressure treatments at 120 MPa (IDF-120-2), respectively. Then the particle size, structural, physicochemical and adsorption properties of different IDF samples were analyzed. After HPMT, the particle size of IDF samples gradiently decreased (p < 0.05), and part of IDF was transferred into soluble dietary fiber (SDF), accompanied by the decrease of hemicellulose and lignin content. In addition, the morphology of the IDF samples became more fragmented and wrinkled, and the two consecutive treatments at 120 MPa significantly damaged the crystalline structure of the IDF. Moreover, the adsorption capacities to water, oil, cholesterol, and NO2- were basically enhanced with the increase of treatment pressure and treatment number. The IDF-120-2 sample had the strongest water/oil-holding, swelling, and cholesterol trapping capacities, and the IDF-120 showed strongest NO2- trapping capacity (pH = 2). Through the correlation analysis, the adsorption capacities were positively to the particle size and SDF content, and negatively correlated with the specific surface area (SSA) and IDF content. The adsorption capacities of IDF for the four substances were positively correlated with each other.

An investigation into the effects of various processing methods on the characteristic compounds of highland barley using a widely targeted metabolomics approach

This study explored the influence of diverse processing methods (cooking (CO), extrusion puffing (EX), and steam explosion puffing (SE), stir-frying (SF) and fermentation (FE)) on highland barley (Qingke) chemical composition using UHPLC-MS/MS based widely targeted metabolomics. Overall, 827 metabolites were identified and categorized into 16 classes, encompassing secondary metabolites, amino acids, nucleotides, lipids, etc. There 43, 85, 131, 51 and 98 differential metabolites were respectively selected from five comparative groups (raw materials (RM) vs CO/EX/SE/SF/FE), mainly involved in amino acids, nucleotides, flavonoids, and alkaloids. Compared to other treated groups, FE group possessed the higher content of crude protein (15.12 g/100 g DW), and the relative levels of free amino acids (1.32 %), key polyphenols and arachidonic acid (0.01 %). EX group had the higher content of anthocyanins (4.22 mg/100 g DW), and the relative levels of free amino acids (2.02 %) and key polyphenols. SE group showed the higher relative levels of phenolic acids (0.14 %), flavonoids (0.20 %) and alkaloids (1.17 %), but the lowest free amino acids (0.75 %). Different processing methods all decreased Qingke's antioxidant capacity, with the iron reduction capacity (988.93 μmol/100 g DW) in SE group was the lowest. On the whole, FE and EX were alleged in improving Qingke's nutritional value. CO and SF were also suitable for Qingke processing since fewer differential metabolites were identified in CO vs RM and SF vs RM groups. Differential metabolites were connected to 14 metabolic pathways, with alanine, aspartate, and glutamate metabolism being central. This study contributed theoretical groundwork for the scientific processing and quality control of Qingke products.

Methylglyoxal scavenging capacity of fiber-bound polyphenols from highland barley during colonic fermentation and its modulation on methylglyoxal-interfered gut microbiota

Methylglyoxal (MGO) scavenging capacity of fiber-bound polyphenols from highland barley during colonic fermentation and its potential role in modulating MGO-induced detrimental effects on gut microbiota were studied. Results showed that only 25.3 % of polyphenols were released after 24 h of colonic fermentation. More than 45.5 % of MGO was scavenged by the residual fiber-bound polyphenols in the model system, showing a vital role in scavenging MGO in the colonic lumen compared to the released polyphenols. Moreover, MGO promoted the increase of gut pathogens (Escherichia-Shigella and Klebsiella) and inhibited the proliferation of Megasphaera, Bifidobacterium and Megamonas, as well as reduced short-chain fatty acids (SCFAs) concentration. The addition of fiber-bound polyphenols of highland barley could effectively counteract MGO-induced detrimental consequences on gut microbiota and SCFAs production. These results demonstrate that fiber-bound polyphenols from highland barley can exert beneficial role through scavenging MGO and promises to be a functional ingredient to maintain colon heath.

Long-term detection of Hartmannibacter diazotrophicus on winter wheat and spring barley roots under field conditions revealed positive correlations on yield parameters with the bacterium abundance

Monitoring of bioinoculants once released into the field remains largely unexplored; thus, more information is required about their survival and interactions after root colonization. Therefore, specific primers were used to perform a long-term tracking to elucidate the effect of Hartmannibacter diazotrophicus on wheat and barley production at two experimental organic agriculture field stations. Three factors were evaluated: organic fertilizer application (with and without), row spacing (15 and 50 cm), and bacterial inoculation (H. diazotrophicus and control without bacteria). Hartmannibacter diazotrophicus was detected by quantitative polymerase chain reaction on the roots (up to 5 × 105 copies g-1 dry weight) until advanced developmental stages under field conditions during two seasons, and mostly in one farm. Correlation analysis showed a significant effect of H. diazotrophicus copy numbers on the yield parameters straw yield (increase of 453 kg ha-1 in wheat compared to the mean) and crude grain protein concentration (increase of 0.30% in wheat and 0.80% in barley compared to the mean). Our findings showed an apparently constant presence of H. diazotrophicus on both wheat and barley roots until 273 and 119 days after seeding, respectively, and its addition and concentration in the roots are associated with higher yields in one crop.

Highland barley β-glucan supplementation attenuated hepatic lipid accumulation in Western diet-induced non-alcoholic fatty liver disease mice by modulating gut microbiota

Non-alcoholic fatty liver disease (NAFLD) has become one of the most common chronic liver diseases worldwide. NAFLD is caused by numerous factors, including the genetic susceptibility, oxidative stress, unhealthy diet, and gut microbiota dysbiosis. Among these, gut microbiota is a key factor and plays an important role in the development of NAFLD. Therefore, modulating the composition and structure of gut microbiota might provide a new intervention strategy for NAFLD. Highland barley β-glucan (HBG) is a polysaccharide that can interact with gut microbiota after entering the lower gastrointestinal tract and subsequently improves NAFLD. Therefore, a Western diet was used to induce NAFLD in mouse models and the intervention effects and underlying molecular mechanisms of HBG on NAFLD mice based on gut microbiota were explored. The results indicated that HBG could regulate the composition of gut microbiota in NAFLD mice. In particular, HBG increased the abundance of short-chain fatty acids (SCFA)-producing bacteria (Prevotella-9, Bacteroides, and Roseburia) as well as SCFA contents. The increase in SCFA contents might activate the adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway, thereby improving the liver lipid metabolism disorder and reducing liver lipid deposition.

Influence of the structure and physicochemical properties of OSA modified highland barley starch based on ball milling assisted treatment

This study aimed to investigate the influence of ball milling assisted treatment on the degree of substitution of octenyl succinic anhydride (OSA) modified highland barley starch (HBS) and on the physicochemical properties and structure of HBS. Scanning electron microscopy (SEM) findings showed that with the increasing of ball milling time, the surface morphology of OSA modified HBS became rougher and rougher and the particle morphology and crystal structure were damaged. When the pretreatment time of ball milling was 40 min, the degree of substitution of OSA modified HBS was 1.32 times higher than that of the conventional modification method. In addition, the longer the ball milling assistant, the longer the short-range ordering of the OSA modified HBS significantly decreased, and the relative crystallinity decreased (from 16.68 % to 7.93 %), leading to a decrease in thermal stability too. However, it greatly enhanced the aging resistance and flowability. In terms of emulsification properties, the emulsification properties of OSA modified HBS increased from 60.67 % to 75.67 %. Therefore, the HBS with better freeze-thaw stability and higher degree of substitution can be prepared by ball milling pretreatment and OSA modification, which provides technical support for further development of starch resources.

Structural Characterization and Antioxidant Activity of β-Glucans from Highland Barley Obtained with Ultrasonic-Microwave-Assisted Extraction

In order to efficiently extract β-glucan from highland barley (HBG) and study its structural characterization and antioxidant activity, ultrasonic-microwave-assisted extraction (UME) was optimized by the response surface method (RSM). Under the optimal extraction conditions of 25.05 mL/g liquid-solid ratio, 20 min ultrasonic time, and 480 W microwave intensity, the DPPH radical scavenging activity of HBG reached 25.67%. Two polysaccharide fractions were purified from HBG, namely HBG-1 and HBG-2. Structural characterization indicated that HBG-1 and HBG-2 had similar functional groups, glycosidic linkages, and linear and complex chain conformation. HBG-1 was mainly composed of glucose (98.97%), while HBG-2 primarily consisted of arabinose (38.23%), galactose (22.01%), and xylose (31.60%). The molecular weight of HBG-1 was much smaller than that of HBG-2. Both HBG-1 and HBG-2 exhibited concentration-dependent antioxidant activity, and HBG-1 was more active. This study provided insights into the efficient extraction of HBG and further investigated the structure and antioxidant activities of purified components HBG-1 and HBG-2. Meanwhile, the results of this study imply that HBG has the potential to be an antioxidant in foods and cosmetics.