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Three endophytic bacteria, namely BvV, BvP and BvL, were newly isolated from the root nodules of bean, pea and lentil plants respectively cultivated in Mascara the northwest of Algeria, and identified by 16S ribosomal RNA gene sequencing as Brevundimonas naejangsanensis. These strains were able to produce hydrolytic enzymes and hydrogen cyanide. All strains produced a growth-promoting hormone, indole acetic acid, varying in concentration from 83.2 to 171.7 µg/mL. The phosphate solubilizing activity of BvV, BvP and BvL varied from 25.5 to 42.02 µg/mL for tricalcium phosphate. The three antagonistic Brevundimonas spp. showed in vitro the most inhibitory effect on mycelial growth of Fusarium redolens FRC (from 78.33 to 85.55%). Strain BvV, BvP and BvL produced also volatile metabolites which inhibited mycelial FRC growth up to 39.2%. All strains showed significant disease reduction in pot experiments. Chickpea Fusarium yellows severity caused by FRC was reduced significantly from 89.3 to 96.6% in the susceptible cultivar ILC 482 treated with antagonistic B. naejangsanensis. The maximum stimulatory effect on chickpea plants growth was observed by inoculation of strain BvV. This treatment resulted in a 7.40-26.21% increase in shoot height as compared to the control plants. It is concluded that the endophytic bacterial strains of B. naejangsanensis having different plant growth promoting (PGP) activities can be considered as beneficial microbes for sustainable agriculture. To our knowledge, this is the first report to use B. naejangsanensis strains as a new biocontrol agent against F. redolens, a new pathogen of chickpea plants causing Fusarium yellows disease in Algeria., (© 2024. Institute of Microbiology, Academy of Sciences of the Czech Republic, v.v.i.)

Heavy metals are prevalent environmental components, but when their concentrations exceed critical thresholds, they pose environmental hazards, disrupting the sustainability of ecosystems. Microorganisms are among the first to encounter the toxic effects of metals. Therefore, it is crucial to understand both the levels and mechanisms of their resistance to maintain their homeostasis under the pressure of extreme factors as well as contribute to increasing the sustainability of ecosystems. The aim of the study was to examine two soil bacterial strains, Brevundimonas vesicularis USM1 and Pseudomonas putida USM4, to assess their resistance levels to toxic metals and to identify the mechanisms behind this resistance. For this purpose, microbiological, statistical, and bioinformatics methods were used. The comparative analysis of the two strains revealed that P. putida USM4 exhibited greater resistance to Cr(VI), Co(II), Cu(II), Ni(II), and Fe(III) compared to B. vesicularis USM1. This was confirmed by the metal concentrations at which the strains could survive, their growth dynamics, and the genetically based resistance mechanisms. These findings enhance our understanding of microbial metal resistance and contribute to the advancement of microbial-based environmental biotechnologies. [ABSTRACT FROM AUTHOR]

Introduction: The production of high-quality food for the growing world population on the one hand and the reduction of chemical-synthetic pesticides on the other hand represents a major challenge for agriculture worldwide. The effectiveness of a combination of microbial and non-microbial biostimulants (BSs) with various nitrogen (N) forms in pathogen defense is discussed as a promising, but still poorly understood bio-based alternative for crop protection. Methods: For this reason, nitrate and stabilized ammonium fertilizer both combined with a consortium of Pseudomonas brassicacearum , Bacillus amyloliquefaciens , and Trichoderma harzianum as soil treatment or with a mixture of seaweed extract (Ascophyllum nodosum) together with chitosan-amended micronutrient fertilizer as foliar spray application were compared under controlled greenhouse conditions. Furthermore, a combination of microbial and different non-microbial BSs (seaweed extracts + chitosan) and micronutrients with nitrate or with stabilized ammonium fertilizer was tested under field conditions to improve nutrient availability, promote plant growth, and suppress Zymoseptoria tritici (Zt) in winter wheat. Results and discussion: While plant-protective effects against Zt by the microbial consortium application could be observed particularly under ammonium fertilization, the application of seaweed extract–chitosan mixture expressed plant defense against Zt more strongly under nitrate fertilization. In the field trial, the combination of microbial consortium with the seaweed extract–chitosan mixture together with micronutrients zinc (Zn) and manganese (Mn) showed positive effects against Zt under ammonium fertilization, associated with increased levels of defense metabolites. Furthermore, the additional input of Zn and copper (Cu) from the chitosan application improved the micronutrient status by minimizing the risk of Zn and Cu deficiency under controlled and field conditions. The use of BSs and the inoculation of Zt did not show any effects on plant growth and yield neither under controlled greenhouse conditions nor in the field. Summarized, microbial and non-microbial BSs separately applied or even combined together as one treatment did not influence plant growth or yield but made a positive contribution to an N form-dependent promotion of pathogen defense. [ABSTRACT FROM AUTHOR]

One of the effective methods to reduce pest damage is to induce resistance in plants. This study investigated the impact of inducing resistance using indigenous isolates of Trichoderma spp. and a commercial product (Trichorun), as well as indigenous isolates of Bacillus subtilis (Ehrenberg) and a commercial product (Serenade), along with chemical compounds like Salicylic acid and Humic acid on the host preference and oviposition of the greenhouse whitefly Trialeurodes vaporariorum (Westwood), as well as on plant growth factors. Four tests were conducted to assess the effects of these treatments on the growth factors of tomato (Vadaro 1012), total phenol levels, host preference and oviposition of whitefly in the greenhouse conditions (25 ± 2°C, 60-70% RH, 16:8 h light: dark). The results indicated that the root treatment of the plants with the native strain of Trichoderma harzianum (Rifai) and the treatment of the combination of Trichorun with Serenade have the best performance in plant growth with a significant increase in the root volume, fresh and dry weight of the root and aerial parts of tomato compared to the control. Compared to control, Serenade treatment showed the best results in measuring total phenol, host preference and oviposition of whitefly in the greenhouse with a significant decrease in the average number of insects attracted to the leaf underside, and egg laying rate in the selective test and emerged adult insects in F1generation in the non-selective test. The findings of this research showed that root inoculation with native isolates of T. harzianum fungus and B. subtilis bacteria increased tomato growth factors, induced resistance to greenhouse whitefly and reduction of host preference and oviposition of whitefly. [ABSTRACT FROM AUTHOR]

The application of beneficial microbial consortium can effectively improve plant disease resistance and its growth. Various fungi were compounded with Bacillus velezensis LJ02 and applied to watermelon plants in this paper. The results showed that the microbial consortium T2 (compounded Bacillus velezensis LJ02 with Aspergillus aculeatus 9) can effectively control gummy stem blight and powdery mildew in watermelon, while the control effect reached 83.56% and 70.93%, respectively (p < 0.05). Compound treatment improved the diversity and richness of the rhizosphere microbial community structure, and the relative abundance of Caulobacterales and Xanthomonadaceae significantly increased after applying T2 to the soil. Meanwhile, the internode length was significantly decreased 28% (p < 0.05), and the maximum leaf length increased 10.33% (p < 0.05). In addition, the microbial consortium delays the maturity of watermelon vegetables. By studying the effects of microbial consortium on watermelon seedlings, our study provides a theoretical basis for the popularization and application of the compound inoculant. [ABSTRACT FROM AUTHOR]

Two Trichoderma strains and three Bacillus strains isolated from the rhizosphere of healthy chickpeas in Algeria were assessed for their phosphate solubilizing capacity in vitro as well as their growth effects on seedlings of the chickpea in pot experiments. The microorganisms tested had higher phosphate-solubilizing activities, with the solubilization index ranging from 2.41 to 7.40. The concentration of solubilized phosphate varied from 30.17 to 157.44 µg/mL. The maximum phosphate-solubilizing activity was observed in the two culture filtrates of Bacillus tequilensis Bt1 (157.44 µg/mL) and Trichoderma orientale T1 (143.33 µg/mL), accompanied by a decrease in pH of the growth medium from 4.51 to 5.75. The application of the strains (B. tequilensis Bt1 and T. orientale T1) separately and in combination had a beneficial effect on germination by promoting the development of the seeds and effectively enhancing plant growth. Chickpea seedlings showed better vegetative growth when treated with a mixture of B. tequilensis Bt1 and T. orientale T1 together than an individual treatment. To our knowledge, this is the first report of the phosphate-solubilizing potential of the combined microorganisms B. tequilensis and T. orientale and their capacity to promote plant growth in chickpeas. [ABSTRACT FROM AUTHOR]

Among the key diseases affecting the asparagus crop (Asparagus officinalis L.), vascular wilting of asparagus caused by Fusarium oxysporum f. sp. asparagi stands out worldwide. This disease significantly shortens the longevity of the crop and limits economic production. Traditional control measures have been largely ineffective, and chemical control methods are difficult to apply, making biological control approaches, specifically the use of Trichoderma, an economical, effective, and risk-free alternative. This study aimed to identify the main factors that affect the efficacy of biopesticides studied as Biological Control Agents (BCAs) against Fusarium wilt in asparagus and to assess the efficacy of Trichoderma-based biopesticides under greenhouse and semi-field conditions. We evaluated the response of three Trichoderma spp. (T. atroviride, T. asperellum, and T. saturnisporum) to environmental variables, such as temperature and water activity, and their antagonistic capacity against Fusarium oxysporum f. sp. asparagi. All three Trichoderma species inhibited the growth of the pathogen in vitro. A decrease in water activity led to a greater reduction in the growth rate. The efficacy of the three biological control agents decreased with higher temperatures, resulting in minimal inhibition, particularly under conditions of restricted available water in the environment. The effect of the fungal inoculum density was also analyzed at two different temperatures. A direct correlation between the amount of inoculum and the score on the Disease Severity Index (DSI) was observed. A notable reduction in DSI was evident in treatments with high inoculum density (106 conidium/mL) for all three species of Trichoderma tested at both temperatures. In greenhouse and semi-field tests, we observed less disease control than expected, although T. asperellum and T. atroviride showed lower disease severity indices and increased the dry weight of seedlings and crowns, whereas T. saturnisporum resulted in the highest disease rate and lowest dry weight. This work highlights that the efficacy of Trichoderma as BCAs is influenced by various factors, including the quantity of soil inocula, and environmental conditions. The study findings have strong implications for selecting appropriate Trichoderma species for controlling specific pathogens under specific environmental conditions. [ABSTRACT FROM AUTHOR]

Several fungi act as parasites for crops causing huge annual crop losses at both pre- and post-harvest stages. For years, chemical fungicides were the solution; however, their wide use has caused environmental contamination and human health problems. For this reason, the use of biofungicides has been in practice as a green solution against fungal phytopathogens. In the context of a more sustainable agriculture, microbial biofungicides have the largest share among the commercial biocontrol products that are available in the market. Precisely, the genus Bacillus has been largely studied for the management of plant pathogenic fungi because they offer a chemically diverse arsenal of antifungal secondary metabolites, which have spawned a heightened industrial engrossment of it as a biopesticide. In this sense, it is indispensable to know the wide arsenal that Bacillus genus has to apply these products for sustainable agriculture. Having this idea in our minds, in this review, secondary metabolites from Bacillus having antifungal activity are chemically and structurally described giving details of their action against several phytopathogens. Knowing the current status of Bacillus secreted antifungals is the base for the goal to apply these in agriculture and it is addressed in depth in the second part of this review. [ABSTRACT FROM AUTHOR]

Pulses have gained popularity over the past few decades due to their use as a source of protein in food and their favorable impact on soil fertility. Despite being essential to modern agriculture, these species face a number of challenges, such as agronomic crop management and threats from plant seed pathogens. This review's goal is to gather information on the distribution, symptomatology, biology, and host range of seedborne pathogens. Important diagnostic techniques are also discussed as a part of a successful process of seed health certification. Additionally, strategies for sustainable control are provided. Altogether, the data collected are suggested as basic criteria to set up a conscious laboratory approach. [ABSTRACT FROM AUTHOR]

The use of organic amendments and appropriate nutrient management practices is essential for sustainable agricultural production. The present study investigated the effect of Gliricidia sepium leafy biomass and NPK (15:15:15) on the growth and yield of tomato plants (Solanum lycopersicum L.). A randomised complete block design with five treatments and four replicates was employed in this experiment. The treatments included T1 (Control), T2 (100% G. sepium leafy biomass), T3 (25% G. sepium leafy biomass + 75% NPK fertiliser), T4 (50% G. sepium leafy biomass + 50% NPK), T5 (100% NPK), and T6 (75% G. sepium leafy biomass + 25% NPK). The application of G. sepium leafy biomass and NPK had significant effects on tomato growth and yield (p<0.05). The combined application of G. sepium leafy biomass and NPK (T4) and the sole application of G. sepium leafy biomass (T2) resulted in the highest plant height, stem girth, and fruit yield compared to the other treatments. Additionally, treatment with 75% Gliricidia leafy biomass and 25% NPK fertiliser (T6) resulted in a superior fruit weight compared to the other treatments. The application of G. sepium leafy biomass (T2) alone and NPK alone (T5) showed a significant improvement in plant growth parameters and fruit yield compared to the control (T1), although the effects were not as pronounced when combined with NPK (T4). The application of NPK fertiliser (T3) also positively influenced plant growth and yield, but the effects were lower compared to T2, T4, and T6. Further studies are warranted to optimise the application rates of G. sepium leafy biomass and NPK for different tomato cultivars and growing conditions. [ABSTRACT FROM AUTHOR]

Fusarium crown rot is the major soil-borne disease of wheat and occurs throughout cereal producing areas of the world including Algeria. This study evaluated 10 bacterial and fungal strains, originating from Algeria as potential biological control agents against three soil-borne phytopathogens responsible for Fusarium crown rot of wheat (Fusarium pseudograminearum ON687723, F. graminearum ON685926 and F. equisti MK361175). All benificial microbial strains tested inhibited the pathogens mycelial growth in vitro. Isolate P58 (Pseudomonas azotoformans NR_113600) was the most effective antagonist against all the test pathogens in direct confrontation assay, and exhibited average of 70% growth inhibition of Fusarium spp. Isolate T2 (Trichoderma gamsii MK361138) proved suppression efficacy in the range of 61.87 to 71.64% toward plant pathogens. Under greenhouse conditions, wheat seeds treated with isolate P58 and T2 separately reduced the severity of crown rot disease significantly and improved the growth parameters of wheat seedlings as compared to control. The combined use of Pseudomonas azotoformans and Trichoderma gamsii increased the effectiveness of the antagonists and promoted wheat growth. Thus, it can be concluded that these strains can be utilized as a biocontrol agent for management of soilborne cereal pathogens. [ABSTRACT FROM AUTHOR]

The use of plastic mulch films is widespread in agriculture for specialty cropping systems because of several benefits. In this article, we critically review, for the first time under a holistic approach, the use of biodegradable plastic mulches (BdPMs) in soil as a sustainable alternative to conventional petroleum-based plastics, highlighting the current state of understanding of their degradation in soil and their effect on soil microorganisms, weed control, and soil properties. In addition, we provide a detailed focus on the history and economic importance of mulching. BdPMs are effective for use in vegetable production in that they improve physical, chemical, and biological soil properties, as well as enhancing microbial biodiversity, controlling weeds, and maintaining soil moisture. BdPMs could be useful to limit the use of agrochemicals and reduce tillage and irrigation supplies for sustainable management. [ABSTRACT FROM AUTHOR]

Cashew wilt, caused by the soil borne fungus Fusarium oxysporum, is a fast spreading disease that is currently threatening the cashew industry in Tanzania, which is a major source of income for cashew growers and the country. The disease causes the death of the trees within a few weeks of infection. Cashew seedlings treated with either Bacillus strains or T. asperellum biofungicides developed significantly (p < 0.05) lower disease severity levels (0–7.54%) compared to untreated cashew seedlings (0–27.27%). No disease symptoms were observed on cashew seedlings treated with Bacillus velezensis strain 13/A + 3 at 0.5, 1.0, and 2.0 mls of a spore suspension at 1 × 104, 2 × 104 and 3 × 104 ml of spore suspension. Under field conditions, cashew trees treated with biofungicides developed significantly (p < 0.001) lower disease severity of 0–11.49% and 0–12.98% in both seasons (2019/2020 and 2020/2021 respectively) compared to the untreated controls (60.05% and 59.71% respectively). Results from this study indicate the potential of the tested biological control agents in the management of cashew wilt disease caused by F. oxysporum. However, further studies are recommended to determine the shelf life and effectiveness of the biological control agents particularly in a field setting, as well as the efficacy of various formulations. [ABSTRACT FROM AUTHOR]

Background: Hiatal hernia (HH) and gastroesophageal reflux disease (GERD) are risk factors for esophageal adenocarcinoma. High positive margin rates and poor survival were described among HH patients undergoing esophagectomy. We sought to describe incidence and impact of HH on outcomes following esophagectomy., Methods: Patients who underwent esophagectomy 2012-2019 for esophago-junctional carcinoma were included. CT studies were blindly reviewed by two radiologists. A third radiologist reviewed cases of disagreement. Hernias ≥ 3 cm were included in the HH group., Results: Overall, 66 patients (33%) had HH ≥ 3 cm. The no hernia group included 12 patients (6%) with < 3 cm HH and 106 (53%) without HH. Preoperative variables were comparable among groups. Location of anastomosis was similar among cohorts and predominantly cervical (n = 97, 82.2% vs 61, 92.4%, p = 0.113). Postoperatively, HH patients had higher incidence of atrial dysrhythmia (n = 11, 16.7% vs n = 6, 5.1% p = 0.015). Rates of R0 resections were similar (n = 62, 93.9%, vs n = 113, 95.8%, p = 0.724). HH patients had higher rates of signet ring cell histology (n = 14, 21.2% vs n = 9, 7.6% p = 0.025); this was confirmed on subgroup analysis including only adenocarcinoma patients (n = 14, 28.6% vs n = 8, 12.3%, p = 0.042). On Cox regression analysis, HH was not associated with disease-free or overall survival (HR 1.308, p = 0.274 and HR .905, p = 0.722)., Conclusions: Patients with preoperative HH had higher rates of postoperative atrial dysrhythmias and signet ring cell features on pathology. In a population with predominant cervical anastomosis, positive margin rates were low and survival comparable among cohorts., (© 2023. The Society for Surgery of the Alimentary Tract.)

The purpose of this research was to collect efficacy data on biological, biochemical, and chemical fungicide seed treatments on hemp (Cannabis sativa L.) to mitigate damping-off and enhance field stand establishment. Seed treatments were evaluated in fields in New York (NY), North Dakota (ND), and Virginia (VA) and at two planting dates in each state in 2020. A single seed lot of a dual-purpose (fiber + grain) cultivar ('Anka') was treated using a laboratory-scale rotary pan coater. Five biological, two biochemical, and four chemical seed treatments were tested. A laboratory germination test revealed that seed treatments did not exhibit phytotoxicity when compared to the non-treated control. A laboratory bioassay with naturally infested soil was used to assess the preliminary activity of seed treatments for protection against damping-off. The biochemical seed treatment Ultim® (active ingredient; organic copper) performed as well as the chemical treatments Apron XL® + Maxim® 4FS and Mertect® 340F in preventing damping-off whereas the biological treatments did not differ from the non-treated control in terms of disease incidence. In all field tests, biological seed treatments did not improve plant stands compared to the non-treated control. Biochemical seed treatments Prudent 44® with Nutrol® (active ingredient; phosphite) and Ultim®, along with chemical seed treatments, had acceptable efficacy and improved stand establishment compared to the non-treated control across field locations. Based on efficacy results from laboratory and field trials, the copper seed treatment has potential for both conventional and organic hemp production. [ABSTRACT FROM AUTHOR]

Chickpea wilt, caused by Fusarium oxysporum f. sp. ciceris, is a disease that decreases chickpea productivity and quality and can reduce its yield by as much as 15%. A newly isolated, moss rhizoid-associated Pseudomonas aeruginosa strain A7, demonstrated strong inhibition of Fusarium oxysporum f. sp. ciceris growth. An in vitro antimicrobial assay revealed A7 to suppress the growth of several fungal and bacterial plant pathogens by secreting secondary metabolites and by producing volatile compounds. In an in vivo pot experiment with Fusarium wilt infection in chickpea, the antagonist A7 exhibited a disease reduction by 77 ± 1.5%, and significantly reduced the disease incidence and severity indexes. Furthermore, A7 promoted chickpea growth in terms of root and shoot length and dry biomass during pot assay. The strain exhibited several traits associated with plant growth promotion, extracellular enzymatic production, and stress tolerance. Under aluminum stress conditions, in vitro growth of chickpea plants by A7 resulted in a significant increase in root length and plant biomass production. Additionally, hallmark genes for antibiotics production were identified in A7. The methanol extract of strain A7 demonstrated antimicrobial activity, leading to the identification of various antimicrobial compounds based on retention time and molecular weight. These findings strongly suggest that the strain's significant biocontrol potential and plant growth enhancement could be a potential environmentally friendly process in agricultural crop production. [ABSTRACT FROM AUTHOR]

Tuber rot disease due to phytopathogen Fusarium oxysporum f. sp. cepae (Foc) infection is one of the main factors causing the decreasing global onions production. This study aims to find bacteria and fungi candidates with Foc antagonistic activity through in vitro tests using dual culture techniques. A total of three bacterial isolates and three fungal isolates isolated from the rhizosphere of healthy onion plants showed the ability to inhibit Fusarium oxysporum growth. LC648364 isolate had an average inhibitory capability of 65.93%. At the same time, LC648367 and LC648368 fungal isolates can inhibit the growth of F. oxysporum by as much as 74.82% and 67.76%, respectively. Molecular analysis based on 16S rRNA markers showed three isolates belonging to the Bacillus. The LC648364 isolates are closely related to species Bacillus sp. strain LLB-17, LC648365 is closely related to B. subtilis strain S11 and LC648366 is closely related to B. cereus strain EM6. For the fungi, based on internal transcribed spacer (ITS) gene markers, there are three isolates. The LC648367 isolate is closely related to Aspergillus tubingensis, LC648368 is closely related to Trichoderma asperellum and LC648369 is closely related to Issatchenkia orientalis. This study can be used to develop indigenous microbial consortiums as biological control agents for phytopathogenic fungi Fusarium tuber rot on onion. [ABSTRACT FROM AUTHOR]

Biocontrol agents serve as a sustainable means of controlling wilt caused by the widespread plant pathogen, Fusarium oxysporum f. sp. lycopersici. The present study aimed to develop water dispersible granules (WDG) using response surface methodology (RSM) for Bacillus subtilis MTCC 2274 and Trichoderma harzianum MTCC 3928, and to compare their antifungal efficacy with other formulations. Further, characterization of the bioactive metabolites responsible for biocontrol was performed. A new microbial formulation, WDG, was developed in the present study with talcum powder (substrate), alginic acid (dispersing agent) and acacia gum (wetting agent) (suspensibility 82.23%; wetting time 2.5 min; dispersion time 10.08 min) that fulfilled the guidelines of Collaborative International Pesticides Analytical Council (CIPAC). In planta study demonstrated that WDG of B. subtilis showed maximum reduction in disease incidence (48%) followed by talc formulation of B. subtilis (44%) and WDG of T. harzianum (42%) with profound effect on plant growth promotion. B. subtilis and T. harzianum demonstrated protease (929 and 846 U ml−1 min−1), chitinase (33.69 and 154 U ml−1 min−1), and β-1,3-glucanase (12.69 and 21.47 U ml−1 min−1) activities. Culture filtrates of B. subtilis and T. harzianum exhibited significant inhibition against mycelial growth of pathogen. The compounds present in the culture filtrates were identified with GC–MS as fatty acids, alkanes, phenols, benzene, pyran derivatives etc. The major non-volatile compounds in bioactive antifungal fraction were identified as derivatives of morpholine and piperdine for T. harzianum and B. subtilis, respectively. The findings propose a multivariate biocontrol mechanism against phytopathogen by production of hydrolytic enzymes, volatile and non-volatile compounds, together with development of an efficient next-generation formulation. [ABSTRACT FROM AUTHOR]

A noticeable research topic in optics is optical phenomena associated with the nonstatic waves. If the parameters of a medium vary by a periodic or randomly exerted perturbation, the waves become nonstatic, leading to a variation in their shapes. The decay of wave amplitudes through dissipation is also an outcome of wave nonstaticity. In this research, we demonstrate that Schrödinger equation allows nonstatic quantum waves even in the situation where the waves neither suffer perturbation nor undergo dissipation. The time behavior of nonstatic waves in such a static environment is investigated in detail in the Fock state at first. And then, we extend our development for such a peculiar wave characteristic to the case of a Gaussian wave evolution which resembles the behavior of classical states. It is shown how to define a quantitative nonstaticity measure which can be used universally beyond the Fock-state nonstatic waves. Understanding the characteristics of nonstatic-wave phenomena may not only provide deeper insight into the essence of nature, but is helpful for practical applications of the wave nonstaticity in science and technology of electromagnetic wave modulations. [ABSTRACT FROM AUTHOR]

The genetic diversity of bacterial populations' nodulating Retama sphaerocarpa grown in the soils of Maamora cork forest (Morocco) was examined. ERIC-PCR fingerprinting of 30 strains distributed them in 2 groups, of which a representative strain from each group was studied by multilocus sequence analysis of the 16S rRNA, atpD, and gyrB genes. The two representative strains RSM25 and RSM32, grouped with "Microvirga tunisiensis". This is the first description of Retama nodule bacteria as members of the genus Microvirga. A nodC-based phylogeny confirmed that the two representative strains RSM25 and RSM32 are affiliated with symbiovar mediterranense. The 2 strains were capable of nodulating not only R. sphaerocarpa but also R. monosperma, R. dasycarpa and L. luteus, and unable to nodulate Phaseolus vulgaris, Vachellia gummifera, Cicer arietinum, Vigna unguiculata and Glycine max. The inoculation of R. sphaerocarpa with RSM25 or RSM32 produced a 1.22-, and 1.36-fold increase in the dry weight of the plants compared to those grown in the presence of 0.05% KNO3. The 2 strains used monosaccharides and disaccharides as the sole C source, but fructose, glucose, galactose, arabinose and starch were not used. They were unable to grow on glycine as a N source. Phosphate solubilization and siderophore production was not detected, but IAA or IAA-related compounds were produced. The alkaline pH of the sampling site soil in the Maamora forest where Retama grows could explain why Microvirga was the dominant species in the root nodules of the plants. [ABSTRACT FROM AUTHOR]

Aims: Low soil temperature in spring is a major constraint for the cultivation of tropical crops in temperate climates. This study aims at the exploitation of synergistic interactions of micronutrients, consortia of plant growth-promoting microorganisms and N forms as cold-stress protectants. Methods: Maize seedlings were exposed for two weeks to low root zone temperatures at 8–14°C under controlled conditions on a silty clay-loam soil (pH 6.9) collected from a maize field cultivation site. A pre-selection trial with fungal and bacterial PGPM strains revealed superior cold-protective performance for a microbial consortium of Trichoderma harzianum OMG16 and Bacillus spp. with Zn/Mn supplementation (CombiA+), particularly in combination with N-ammonium as a starting point for the characterization of the underlying physiological and molecular mechanisms. Results: In nitrate-treated plants, the cold stress treatment increased oxidative leaf damage by 133% and reduced the shoot biomass by 25%, related with reduced acquisition of phosphate (P), zinc (Zn) and manganese (Mn). The supplying of N as ammonium improved the Zn and Mn nutritional status and increased the ABA shoot concentration by 33%, as well as moderately increased detoxification of reactive oxygen species (ROS). Moreover, use of N as ammonium also increased the root auxin (IAA) concentration (+76%), with increased expression of auxin-responsive genes, involved in IAA synthesis (ZmTSA), transport (ZmPIN1a), and perception (ZmARF12). Additional inoculation with the microbial consortium promoted root colonization with the inoculant strain T. harzianum OMG16 in combination with ammonium fertilization (+140%). An increased ABA/cytokinin ratio and increased concentrations of jasmonic (JA) and salicylic acids (SA) were related to a further increase in enzymatic and non-enzymatic ROS detoxification. Additional supplementation with Zn and Mn further increased shoot IAA, root length and total antioxidants, resulting in the highest shoot biomass production and the lowest leaf damage by oxidative chemical species. Conclusion: Our results suggest the mitigation of cold stress and reduction of stress priming effects on maize plants due to improved ROS detoxification and induction of hormonal stress adaptations relying on the strategic combination of stress-protective nutrients with selected microbial inoculants. [ABSTRACT FROM AUTHOR]

Vascular wilt caused by Fusarium oxysporum f. sp. ciceri (FOC) is a disease that limits the yield of chickpea in Algeria. Biological control with antagonistic microorganisms is one of the alternatives methods to fight this fungal disease. In this work, we tested an actinomycete Streptomyces ACT2 against 03 isolates of FOC (FOC8, FOC13, FOC 15) in vivo on three varieties of chickpea including a sensitive variety (ILC-482) and two varieties moderately tolerant (Col-27, PPC-25) in order to highlight its effect on the reduction or suppression of this disease. The results obtained showed that the degree of suppression of the disease by ACT2 varies from one variety to another and from one FOC isolate to another. The maximum suppression of the disease was observed in the Col-27 variety. The ACT2 isolate showed higher levels of disease suppression in both the moderately sensitive Col-27 (13.68%) and PPC- 25 (18.78%) varieties than the sensitive variety ILC-482 (8.76%). The Streptomyces (ACT2) can be used as a biological protector of chickpea infected by the pathogen Fusarium oxysporum f. sp. ciceri. [ABSTRACT FROM AUTHOR]

The properties of the geometric phase in the coherent state for a self-oscillating nanowire that can be used to generate an AC signal through field emissions have been investigated using the invariant operator method and the unitary transformation approach. The system transformed by a suitable unitary operator from the complicated original system for the nanowire oscillation is described in terms of the simple harmonic oscillator. This provides a clue which enables the investigation of quantum properties, including the geometric phase, of the complicated time-dependent system, because quantum solutions and associated mathematical relations for the simple harmonic oscillator are well known. By using the unitary relation between the original and the transformed systems, the geometric phase in the coherent state has been rigorously evaluated. The resulting geometric phase is represented in terms of a time function which is the solution of a nonlinear differential equation. The time behavior of the geometric phase is analyzed in detail from the plots for its evolution, depicted using the relevant numerical data. We have confirmed that the geometric phase tends to exhibit a quasi-periodical behavior in some situations, but largely it is sensitive to the change in parameters. Our research is of great importance for understanding not only the topological properties of self-oscillating nanowires but the elastic, mechanical, and physical ones as well. [ABSTRACT FROM AUTHOR]

Presently, agriculture worldwide is facing the major challenge of feeding the increasing population sustainably. The conventional practices have not only failed to meet the projected needs, but also led to tremendous environmental consequences. Hence, to ensure a food-secure and environmentally sound future, the major thrust is on sustainable alternatives. Due to challenges associated with conventional means of application of biocontrol agents in the management of biotic stresses in agroecosystems, significant transformations in this context are needed. The crucial role played by soil microbiome in efficiently and sustainably managing the agricultural production has unfolded a newer approach of rhizosphere engineering that shows immense promise in mitigating biotic stresses in an eco-friendly manner. The strategy of generating synthetic microbial communities (SynComs), by integrating omics approaches with traditional techniques of enumeration and in-depth analysis of plant-microbe interactions, is encouraging. The review discusses the significance of the rhizospheric microbiome in plant's fitness, and its manipulation for enhancing plant attributes. The focus of the review is to critically analyse the potential tools for the design and utilization of SynComs as a sustainable approach for rhizosphere engineering to ameliorate biotic stresses in plants. Furthermore, based on the synthesis of reports in the area, we have put forth possible solutions to some of the critical issues that impair the large-scale application of SynComs in agriculture., (© 2022 The Society for Applied Microbiology.)

Bacillus amyloliquefaciens IIHR BA2 strain was tested in vitro for its compatibility with five different bio-control agents viz., Bacillus subtilis, Pseudomonas fluorescens, Trichoderma viride, Paecilomyces lilacinus and Pochonia chlamydosporia. Among them, T. viride and B. subtilis showed maximum compatibility of 62.80% and 60.00% respectively followed by Pochonia chlamydosporia (50.90%), Paecilomyces lilacinus (48.60%) and Pseudomonas fluorescens (25.00%). Compatibility of B. amyloliquefaciens IIHR BA2 was also tested with seven commercial agrochemicals viz., K-cyclin, captan, mancozeb, copper oxychloride, fenamidone + mancozeb, carbendazim and wettable sulphur at different concentrations. The results revealed that carbendazim and wettable sulphur were highly compatible at the concentration of 500 ppm but K-Cyclin, captan, mancozeb, copper oxychloride, fenamidone + mancozeb exhibited high toxicity and observed no growth at all the tested concentrations with B. amyloliquefaciens IIHR BA2. These results are very crucial for decision making in Integrated Nematode Management programmes and also in development of consortia formulations. [ABSTRACT FROM AUTHOR]

Tuber rot disease due to phytopathogen Fusarium oxysporum f. sp. cepae (Foc) infection is one of the main factors causing the decreasing global onions production. This study aims to find bacteria and fungi candidates with Foc antagonistic activity through in vitro tests using dual culture techniques. A total of three bacterial isolates and three fungal isolates isolated from the rhizosphere of healthy onion plants showed the ability to inhibit Fusarium oxysporum growth. LC648364 isolate had an average inhibitory capability of 65.93%. At the same time, LC648367 and LC648368 fungal isolates can inhibit the growth of F. oxysporum by as much as 74.82% and 67.76%, respectively. Molecular analysis based on 16S rRNA markers showed three isolates belonging to the Bacillus. The LC648364 isolates are closely related to species Bacillus sp. strain LLB-17, LC648365 is closely related to B. subtilis strain S11 and LC648366 is closely related to B. cereus strain EM6. For the fungi, based on internal transcribed spacer (ITS) gene markers, there are three isolates. The LC648367 isolate is closely related to Aspergillus tubingensis, LC648368 is closely related to Trichoderma asperellum and LC648369 is closely related to Issatchenkia orientalis. This study can be used to develop indigenous microbial consortiums as biological control agents for phytopathogenic fungi Fusarium tuber rot on onion., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background The benefit of neoadjuvant chemotherapy ( NCT) for early-stage oesophageal cancer is unknown. The aim of this study was to assess whether NCT improves the outcome of patients with stage I or II disease. Methods Data were collected from 30 European centres from 2000 to 2010. Patients who received NCT for stage I or II oesophageal cancer were compared with patients who underwent primary surgery with regard to postoperative morbidity, mortality, and overall and disease-free survival. Propensity score matching was used to adjust for differences in baseline characteristics. Results Of 1173 patients recruited (181 NCT, 992 primary surgery), 651 (55·5 per cent) had clinical stage I disease and 522 (44·5 per cent) had stage II disease. Comparisons of the NCT and primary surgery groups in the matched population (181 patients in each group) revealed in-hospital mortality rates of 4·4 and 5·5 per cent respectively ( P = 0·660), R0 resection rates of 91·7 and 86·7 per cent ( P = 0·338), 5-year overall survival rates of 47·7 and 38·6 per cent (hazard ratio ( HR) 0·68, 95 per cent c.i. 0·49 to 0·93; P = 0·016), and 5-year disease-free survival rates of 44·9 and 36·1 per cent ( HR 0·68, 0·50 to 0·93; P = 0·017). Conclusion NCT was associated with better overall and disease-free survival in patients with stage I or II oesophageal cancer, without increasing postoperative morbidity. [ABSTRACT FROM AUTHOR]

A major current challenge is to increase the food production while preserving natural resources. Agricultural practices that enhance the productivity and progressively improve the soil quality are relevant to face this challenge. Trichoderma species are widely used in agriculture to stimulate the plant growth and to control different pathogens affecting crops, representing useful tools for sustainable food production. This mini-review summarizes applications of Trichoderma strains in agriculture to control fungal pathogens, nematodes and insects, the involved biocontrol mechanisms, efficacy and inoculation forms in greenhouse, field and post-harvest conditions. Aspects of Trichoderma handling that influence on biocontrol efficacy such as preventive treatments, frequency of applications and delivery methods are discussed. Strategies useful to improve the antagonistic performance such as the use of native strains, protoplast fusion, formulation, growth on pathogen cell wall medium and combination with other antagonists in integrated treatments are discussed. This mini-review provides practical knowledge to design safe and optimal biocontrol strategies based on Trichoderma and pose challenges to expand its antagonist performance.

Legumes obtain nitrogen from air through rhizobia residing in root nodules. Some species of rhizobia can colonize cereals but do not fix nitrogen on them. Disabling native regulation can turn on nitrogenase expression, even in the presence of nitrogenous fertilizer and low oxygen, but continuous nitrogenase production confers an energy burden. Here, we engineer inducible nitrogenase activity in two cereal endophytes (Azorhizobium caulinodans ORS571 and Rhizobium sp. IRBG74) and the well-characterized plant epiphyte Pseudomonas protegens Pf-5, a maize seed inoculant. For each organism, different strategies were taken to eliminate ammonium repression and place nitrogenase expression under the control of agriculturally relevant signals, including root exudates, biocontrol agents and phytohormones. We demonstrate that R. sp. IRBG74 can be engineered to result in nitrogenase activity under free-living conditions by transferring a nif cluster from either Rhodobacter sphaeroides or Klebsiella oxytoca. For P. protegens Pf-5, the transfer of an inducible cluster from Pseudomonas stutzeri and Azotobacter vinelandii yields ammonium tolerance and higher oxygen tolerance of nitrogenase activity than that from K. oxytoca. Collectively, the data from the transfer of 12 nif gene clusters between 15 diverse species (including Escherichia coli and 12 rhizobia) help identify the barriers that must be overcome to engineer a bacterium to deliver a high nitrogen flux to a cereal crop.