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Simple Summary: Productivity in agriculture is affected by nutrient-deficit soil, a phenomenon caused by anthropogenic activities or by geographical location, such as in arid zones. The pH affects the availability of chemical compounds, which is why it is an elementary parameter for the survival of organisms. These conditions on the soil cause the inhibition of microorganism growth. Trichoderma are filamentous fungi located in a great diversity of ecosystems. They are commonly associated with plants and carry out fundamental activities in the development, biological control, and nutrition of plants. The study of areas with extreme conditions represents a valuable source of new strains with adaptations to environmental demands; locating sites where there are fungi with tolerance, evolution events, and adaptations to biotic and abiotic conditions provides evidence that there are microorganisms with the potential to improve soils and generate a positive effect on vegetable crops. Trichoderma species are filamentous fungi that support plant health and confer improved growth, disease resistance, and abiotic stress tolerance. The objective of this study is to describe the physiological characteristics of the abundance and structure of Trichoderma model strains from arid zones and evaluate and describe their possible adaptation and modulation in alkaline pH. The presence of biotic factors such as phytopathogens forces farmers to take more actions such as using pesticides. In addition, factors such as the lack of water worldwide lead to losses in agricultural production. Therefore, the search for biocontrol microorganisms that support drought opens the door to the search for variations in the molecular mechanisms involved in these phenomena. In our case, we isolated 11 tested Trichoderma fungal strains from samples collected both from the rhizosphere and roots from two endemic plants. We probed their molecular markers to obtain their identity and assessed their resistance to alkaline conditions, as well as their response to mycoparasitism, plant growth promotion, and drought stress. The findings were worthy of being analyzed in depth. Three fungal taxa/species were grouped by phylogenetic/phenotypic characteristics; three T. harzianum strains showed outstanding capabilities to adapt to alkalinity stress. They also showed antagonistic activity against three phytopathogenic fungi. Additionally, we provided evidence of significant growth promotion in Sorghum bicolor seedlings under endemic agriculture conditions and a reduction in drought damage with Trichoderma infection. Finally, beneficial fungi adapted to specific ambient niches use various molecular mechanisms to survive and modulate their metabolism. [ABSTRACT FROM AUTHOR]

Trichoderma species are filamentous fungi that support plant health and confer improved growth, disease resistance, and abiotic stress tolerance. The objective of this study is to describe the physiological characteristics of the abundance and structure of Trichoderma model strains from arid zones and evaluate and describe their possible adaptation and modulation in alkaline pH. The presence of biotic factors such as phytopathogens forces farmers to take more actions such as using pesticides. In addition, factors such as the lack of water worldwide lead to losses in agricultural production. Therefore, the search for biocontrol microorganisms that support drought opens the door to the search for variations in the molecular mechanisms involved in these phenomena. In our case, we isolated 11 tested Trichoderma fungal strains from samples collected both from the rhizosphere and roots from two endemic plants. We probed their molecular markers to obtain their identity and assessed their resistance to alkaline conditions, as well as their response to mycoparasitism, plant growth promotion, and drought stress. The findings were worthy of being analyzed in depth. Three fungal taxa/species were grouped by phylogenetic/phenotypic characteristics; three T. harzianum strains showed outstanding capabilities to adapt to alkalinity stress. They also showed antagonistic activity against three phytopathogenic fungi. Additionally, we provided evidence of significant growth promotion in Sorghum bicolor seedlings under endemic agriculture conditions and a reduction in drought damage with Trichoderma infection. Finally, beneficial fungi adapted to specific ambient niches use various molecular mechanisms to survive and modulate their metabolism.

Rhizoctonia root-rot disease causes severe economic losses in a wide range of crops, including Vicia faba worldwide. Currently, biosynthesized nanoparticles have become super-growth promoters as well as antifungal agents. In this study, biosynthesized selenium nanoparticles (Se-NPs) have been examined as growth promoters as well as antifungal agents against Rhizoctonia solani RCMB 031001 in vitro and in vivo. Se-NPs were synthesized biologically by Bacillus megaterium ATCC 55000 and characterized by using UV-Vis spectroscopy, XRD, dynamic light scattering (DLS), and transmission electron microscopy (TEM) imaging. TEM and DLS images showed that Se-NPs are mono-dispersed spheres with a mean diameter of 41.2 nm. Se-NPs improved healthy Vicia faba cv. Giza 716 seed germination, morphological, metabolic indicators, and yield. Furthermore, Se-NPs exhibited influential antifungal activity against R. solani in vitro as well as in vivo. Results revealed that minimum inhibition and minimum fungicidal concentrations of Se-NPs were 0.0625 and 1 mM, respectively. Moreover, Se-NPs were able to decrease the pre-and post-emergence of R. solani damping-off and minimize the severity of root rot disease. The most effective treatment method is found when soaking and spraying were used with each other followed by spraying and then soaking individually. Likewise, Se-NPs improve morphological and metabolic indicators and yield significantly compared with infected control. In conclusion, biosynthesized Se-NPs by B. megaterium ATCC 55000 are a promising and effective agent against R. solani damping-off and root rot diseases in Vicia faba as well as plant growth inducer. [ABSTRACT FROM AUTHOR]

Plant diseases are one of the main factors responsible for food loss in the world, and 20–40% of such loss is caused by pathogenic infections. Botrytis cinerea is the most widely studied necrotrophic phytopathogenic fungus. It is responsible for incalculable economic losses due to the large number of host plants affected. Today, B. cinerea is controlled mainly by synthetic fungicides whose frequent application increases risk of resistance, thus making them unsustainable in terms of the environment and human health. In the search for new alternatives for the biocontrol of this pathogen, the use of endophytic microorganisms and their metabolites has gained momentum in recent years. In this work, we isolated endophytic bacteria from Zea mays cultivated in Colombia. Several strains of Bacillus subtilis, isolated and characterized in this work, exhibited growth inhibition against B. cinerea of more than 40% in in vitro cultures. These strains were characterized by studying several of their biochemical properties, such as production of lipopeptides, potassium solubilization, proteolytic and amylolytic capacity, production of siderophores, biofilm assays, and so on. We also analyzed: (i) its capacity to promote maize growth (Zea mays) in vivo, and (ii) its capacity to biocontrol B. cinerea during in vivo infection in plants (Phaseolus vulgaris).

The present experiment was carried out in Autumn 2018 to study the effect of many beneficial bio factors: bacteria mix powder (Bacillus + Pseudomonas + Azospirillum), three levels (0.3, 0.6, 0.9) gm ground application and yeast three levels (0,10,20) gm / L. foliar application with its interaction on some vegetative characters on eggplant plant Solanum melongena L. Results of this work showed the positive beneficial effects of the biofactors as compared with the control treatment. The treatment (Bacteria 0.3 gm + yeast 10 gm/L.) appeared the highest value for plant height, stem diameter, number of leaves and dry shoot weight, while the treatment (bacteria 0.9gm + yeast 20gm/ L.) got the highest value for chlorophyll content character. [ABSTRACT FROM AUTHOR]

Antagonistic soil microorganisms, which are non-toxic, harmless non-pollutants, can effectively reduce the density of pathogenic species by some ways. Bacillus velezensis strain S3-1 was isolated from the rhizosphere soil of cucumber, and was shown to inhibit plant pathogens, promote plant growth and efficiently colonize rhizosphere soils. The strain produced 13 kinds of lipopeptide antibiotics, belonging to the surfactin, iturin and fengycin families. Here, we presented the complete genome sequence of S3-1. The genome consists of one chromosome without plasmids and also contains the biosynthetic gene cluster that encodes difficidin, macrolactin, surfactin and fengycin. The genome contains 86 tRNA genes, 27 rRNA genes and 57 antibiotic-related genes. The complete genome sequence of B. velezensis S3-1 provides useful information to further detect the molecular mechanisms behind antifungal actions, and will facilitate its potential as a biological pesticide in the agricultural industry. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have a broad range of applications and are generally considered human-engineered nanomaterials. However, carbon nanostructures have been found in ice cores and oil wells, suggesting that nature may provide appropriate conditions for CNT synthesis. During forest wildfires, materials such as turpentine and conifer tissues containing iron under high temperatures may create chemical conditions favorable for CNT generation, similar to those in synthetic methods. Here, we show evidence of naturally occurring multiwalled carbon nanotubes (MWCNTs) produced from Pinus oocarpa and Pinus pseudostrobus, following a forest wildfire. The MWCNTs showed an average of 10 walls, with internal diameters of ∼2.5 nm and outer diameters of ∼14.5 nm. To verify whether MWCNT generation during forest wildfires has a biological effect on some characteristic plant species of these ecosystems, germination and development of seedlings were conducted. Results show that the utilization of comparable synthetic MWCNTs increased seed germination rates and the development of Lupinus elegans and Eysenhardtia polystachya, two plants species found in the burned forest ecosystem. The finding provides evidence that supports the generation and possible ecological functions of MWCNTs in nature.

Simple Summary: Plant extracts, including essential oils, are a viable alternative method for controlling plant diseases. This work deals with the exploitation of fennel seed essential oil (FSEO) to inhibit Fusarium solani and control Fusarium root rot disease in Vicai faba. In vitro FSEO inhibited mycelium growth by up to 80% at 400 µL/mL of FSEO. In vivo, the protective effects against Fusarium root rot disease were recorded when FSEO was applied to Vicia faba seeds. The FSEO reduced the disease severity from 98% in plants grown in infested soil with Fusarium solani to 60.1% in plants that previously had their seeds treated with FSEO. GC-MS spectrometry analyses showed that the major chemical components in the essential oil were D-limonene, menthol, estragole and 2-decenal. Applications of the essential oil resulted in increased total phenolic and flavonoid contents in leaves compared with untreated inoculated (control) plants. The defense-related genes, such as defensin and chitinase, were differentially expressed. This study revealed that the essential oil of fennel seed was effective as a control agent against Fusarium root rot in broad beans. Fusarium solani, the causative agent of root rot disease is one of the major constraints of faba bean (Vicia faba L.) yield worldwide. Essential oils have become excellent plant growth stimulators besides their antifungal properties. Foeniculum vulgare Mill. (fennel) is a familiar medicinal plant that has inhibitory effects against phytopathogenic fungi. Herein, different concentrations of fennel seed essential oil (FSEO) (12.5, 25, 50, 100, 200 and 400 μL/mL) were examined against F. solani KHA10 (accession number MW444555) isolated from rotted roots of faba bean in vitro and in vivo. The chemical composition of FSEO, through gas chromatography/mass spectroscopy, revealed 10 major compounds. In vitro, FSEO inhibited F. solani with a minimum inhibitory concentration (MIC) of 25 µL/mL. In vivo, FSEO suppressed Fusarium root rot disease in Vicia faba L. by decreasing the disease severity (61.2%) and disease incidence (50%), and acted as protective agent (32.5%) of Vicia faba L. Improvements in morphological and biochemical parameters were recorded in FSEO-treated faba seeds. Moreover, the expression level of the defense-related genes defensin and chitinase was noticeably enhanced in treated plants. This study suggested using FSEO as a promising antifungal agent against F. solani not only to control root rot disease but also to enhance plant growth and activate plant defense. [ABSTRACT FROM AUTHOR]

Simple Summary: Plant–microorganism associations date back more than 400 million years. Plants host microorganisms that establish many different relationships with them, some negative and others very positive for both organisms. A type of this relationship is established with microorganisms that live inside them, known as endophytic microorganisms; they can include bacteria, yeasts, and fungi. In this study, we isolate endophytic bacteria from maize plants, and we characterize them in order to check their potential for being used as biocontrol agents against Botrytis cinerea, one of the most important phytopathogenic fungi in the world. The endophytic bacteria showed this antagonistic effect during in vitro assay and also during in vivo assay in Phaseolus vulgaris. At the same time, they showed the capacity for promoting growth in Zea mays plants. Plant diseases are one of the main factors responsible for food loss in the world, and 20–40% of such loss is caused by pathogenic infections. Botrytis cinerea is the most widely studied necrotrophic phytopathogenic fungus. It is responsible for incalculable economic losses due to the large number of host plants affected. Today, B. cinerea is controlled mainly by synthetic fungicides whose frequent application increases risk of resistance, thus making them unsustainable in terms of the environment and human health. In the search for new alternatives for the biocontrol of this pathogen, the use of endophytic microorganisms and their metabolites has gained momentum in recent years. In this work, we isolated endophytic bacteria from Zea mays cultivated in Colombia. Several strains of Bacillus subtilis, isolated and characterized in this work, exhibited growth inhibition against B. cinerea of more than 40% in in vitro cultures. These strains were characterized by studying several of their biochemical properties, such as production of lipopeptides, potassium solubilization, proteolytic and amylolytic capacity, production of siderophores, biofilm assays, and so on. We also analyzed: (i) its capacity to promote maize growth (Zea mays) in vivo, and (ii) its capacity to biocontrol B. cinerea during in vivo infection in plants (Phaseolus vulgaris). [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have a broad range of applications and are generally considered human-engineered nanomaterials. However, carbon nanostructures have been found in ice cores and oil wells, suggesting that nature may provide appropriate conditions for CNT synthesis. During forest wildfires, materials such as turpentine and conifer tissues containing iron under high temperatures may create chemical conditions favorable for CNT generation, similar to those in synthetic methods. Here, we show evidence of naturally occurring multiwalled carbon nanotubes (MWCNTs) produced from Pinus oocarpa and Pinus pseudostrobus, following a forest wildfire. The MWCNTs showed an average of 10 walls, with internal diameters of ∼2.5 nm and outer diameters of ∼14.5 nm. To verify whether MWCNT generation during forest wildfires has a biological effect on some characteristic plant species of these ecosystems, germination and development of seedlings were conducted. Results show that the utilization of comparable synthetic MWCNTs increased seed germination rates and the development of Lupinus elegans and Eysenhardtia polystachya , two plants species found in the burned forest ecosystem. The finding provides evidence that supports the generation and possible ecological functions of MWCNTs in nature., Competing Interests: The authors declare there are no competing interests.