Phytohormones (Auxin, Gibberellin) and ACC Deaminase In Vitro Synthesized by the Mycoparasitic Trichoderma DEMTkZ3A0 Strain and Changes in the Level of Auxin and Plant Resistance Markers in Wheat Seedlings Inoculated with this Strain Conidia

Both hormonal balance and plant growth may be shaped by microorganisms synthesizing phytohormones, regulating its synthesis in the plant and inducing plant resistance by releasing elicitors from cell walls (CW) by degrading enzymes (CWDE). It was shown that the Trichoderma DEMTkZ3A0 strain, isolated from a healthy rye rhizosphere, colonized the rhizoplane of wheat seedlings and root border cells (RBC) and caused approximately 40% increase of stem weight. The strain inhibited (in over 90%) the growth of polyphagous Fusarium spp. (F. culmorum, F. oxysporum, F. graminearum) phytopathogens through a mechanism of mycoparasitism. Chitinolytic and glucanolytic activity, strongly stimulated by CW of F. culmorum in the DEMTkZ3A0 liquid culture, is most likely responsible for the lysis of hyphae and macroconidia of phytopathogenic Fusarium spp. as well as the release of plant resistance elicitors. In DEMTkZ3A0 inoculated plants, an increase in the activity of the six tested plant resistance markers and a decrease in the concentration of indoleacetic acid (IAA) auxin were noted. IAA and gibberellic acid (GA) but also the 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase (ACCD) enzyme regulating ethylene production by plant were synthesized by DEMTkZ3A0 in the liquid culture. IAA synthesis was dependent on tryptophan and negatively correlated with temperature, whereas GA synthesis was positively correlated with the biomass and temperature.

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Alleviation of Salt Stress in Wheat Seedlings via Multifunctional Bacillus aryabhattai PM34: An In-Vitro Study

Sustainability ◽

10.3390/su13148030 ◽

2021 ◽

Vol 13 (14) ◽

pp. 8030

Author(s):

Shehzad Mehmood ◽

Amir Abdullah Khan ◽

Fuchen Shi ◽

Muhammad Tahir ◽

Tariq Sultan ◽

...

Keyword(s):

Salt Stress ◽

Plant Growth ◽

Stress Tolerance ◽

Bacterial Strain ◽

Acc Deaminase ◽

Wheat Growth ◽

Wheat Seedlings ◽

Pgp Traits ◽

Bacillus Aryabhattai

Plant growth-promoting rhizobacteria play a substantial role in plant growth and development under biotic and abiotic stress conditions. However, understanding about the functional role of rhizobacterial strains for wheat growth under salt stress remains largely unknown. Here we investigated the antagonistic bacterial strain Bacillus aryabhattai PM34 inhabiting ACC deaminase and exopolysaccharide producing ability to ameliorate salinity stress in wheat seedlings under in vitro conditions. The strain PM34 was isolated from the potato rhizosphere and screened for different PGP traits comprising nitrogen fixation, potassium, zinc solubilization, indole acetic acid, siderophore, and ammonia production, along with various extracellular enzyme activities. The strain PM34 showed significant tolerance towards both abiotic stresses including salt stress (NaCl 2 M), heavy metal (nickel, 100 ppm, and cadmium, 300 ppm), heat stress (60 °C), and biotic stress through mycelial inhibition of Rhizoctonia solani (43%) and Fusarium solani (41%). The PCR detection of ituC, nifH, and acds genes coding for iturin, nitrogenase, and ACC deaminase enzyme indicated the potential of strain PM34 for plant growth promotion and stress tolerance. In the in vitro experiment, NaCl (2 M) decreased the wheat growth while the inoculation of strain PM34 enhanced the germination% (48%), root length (76%), shoot length (75%), fresh biomass (79%), and dry biomass (87%) over to un-inoculated control under 2M NaCl level. The results of experiments depicted the ability of antagonistic bacterial strain Bacillus aryabhattai PM34 to augment salt stress tolerance when inoculated to wheat plants under saline environment.

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Influence of temperature and species origin on Fusarium spp. and Microdochium nivale pathogenicity to wheat seedlings

Plant Protection Science ◽

10.17221/12/2009-pps ◽

2010 ◽

Vol 46 (No. 2) ◽

pp. 59-65 ◽

Cited By ~ 10

Author(s):

K. Hudec ◽

D. Muchová

Keyword(s):

Slovak Republic ◽

Fusarium Species ◽

Microdochium Nivale ◽

Wheat Grain ◽

Mountain Regions ◽

Fusarium Spp ◽

Wheat Seedlings ◽

Influence Of Temperature ◽

Species Origin

The influence of temperature and species origin on the in vitro growth rate and pathogenicity of Fusarium and Microdochium nivale (F. avenaceum, F. culmorum, F. graminearum, F. poae, and M. nivale) to wheat seedlings was examined. The mycelial growth of Fusarium avenaceum, F. culmorum, F. graminearum, and F. poae was the fastest at 25°C, and of M. nivale at 15°C. The isolates of F. culmorum, F. graminearum and F. poae originating from mountain regions grew significantly faster at 15°C than those from flatland regions. The isolates from flatland regions grew significantly faster at 25°C than those from mountain regions. F. culmorum and F. graminearum were the most pathogenic species to the root development. The retardation of wheat grain germination caused by the tested species was assessed in descending order: F. culmorum, F. graminearum, M. nivale, F. avenaceum, F. poae. The biomass growth retardation at 15°C was assessed in descending order: F. culmorum, F. graminearum, M. nivale, F. avenaceum, F. poae; at 25°C as follows: F. graminearum, F. culmorum, F. avenaceum, M. nivale, F. poae. The isolates of M. nivale and F. poae originating from mountain regions were significantly more pathogenic than those from flatland regions. The results suggest that there exist different temperature ecotypes and pathotypes of Fusarium species and Microdochium nivale across the territory of the Slovak Republic.

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Synthesis of Indoleacetic Acid, Gibberellic Acid and ACC-Deaminase by Mortierella Strains Promote Winter Wheat Seedlings Growth under Different Conditions

International Journal of Molecular Sciences ◽

10.3390/ijms19103218 ◽

2018 ◽

Vol 19 (10) ◽

pp. 3218 ◽

Cited By ~ 12

Author(s):

Ewa Ozimek ◽

Jolanta Jaroszuk-Ściseł ◽

Justyna Bohacz ◽

Teresa Korniłłowicz-Kowalska ◽

Renata Tyśkiewicz ◽

...

Keyword(s):

Gibberellic Acid ◽

Winter Wheat ◽

Indoleacetic Acid ◽

Acc Deaminase ◽

Its Region ◽

Temperate Climate ◽

Fresh Weight ◽

Promoting Effect ◽

Wheat Seedlings ◽

Shoot Fresh Weight

The endogenous pool of phytoregulators in plant tissues supplied with microbial secondary metabolites may be crucial for the development of winter wheat seedlings during cool springs. The phytohormones may be synthesized by psychrotrophic microorganisms in lower temperatures occurring in a temperate climate. Two fungal isolates from the Spitzbergen soils after the microscopic observations and “the internal transcribed spacer” (ITS) region molecular characterization were identified as Mortierella antarctica (MA DEM7) and Mortierella verticillata (MV DEM32). In order to study the synthesis of indoleacetic acid (IAA) and gibberellic acid (GA), Mortierella strains were grown on media supplemented with precursor of phytohormones tryptophan at 9, 15 °C, and 20 °C for nine days. The highest amount of IAA synthesis was identified in MV DEM32 nine-day-culture at 15 °C with 1.5 mM of tryptophan. At the same temperature (15 °C), the significant promoting effect (about 40% root and shoot fresh weight) of this strain on seedlings was observed. However, only MA DEM-7 had the ACC (1-aminocyclopropane-1-carboxylate) deaminase activity with the highest efficiency at 9 °C and synthesized IAA without tryptophan. Moreover, at the same conditions, the strain was confirmed to possess the strong promoting effect (about 40% root and 24% shoot fresh weight) on seedlings. Both strains synthesized GA in all tested terms and temperatures. The studied Mortierella strains had some important traits that led them to be considered as microbial biofertilizers components, improving plant growth in difficult temperate climates.

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Biological Control of Fusarium Crown and Root Rot of Wheat by Streptomyces Isolates – It’s Complicated

Phytobiomes Journal ◽

10.1094/pbiomes-11-18-0052-r ◽

2019 ◽

Vol 3 (1) ◽

pp. 52-60 ◽

Cited By ~ 3

Author(s):

Mark Winter ◽

Peter L. Samuels ◽

Lindsey K. Otto-Hanson ◽

Ruth Dill-Macky ◽

Linda L. Kinkel

Keyword(s):

Biological Control ◽

Root Rot ◽

In Vitro Tests ◽

Fusarium Spp ◽

Wheat Seedlings ◽

Genus Streptomyces ◽

Stem Base ◽

Crown And Root Rot ◽

Streptomyces Isolate

The predominant causal agents of Fusarium crown and root rot (FCR) of wheat, along with Fusarium pseudograminearum, are F. graminearum and F. culmorum. Members of the Gram-positive bacterial genus Streptomyces have been shown to inhibit isolates of the genus Fusarium, and Fusarium spp. isolates are also able to inhibit Streptomyces isolates in vitro. However, little is known about these complex antagonistic interactions and the potential for inhibitory Streptomyces to reduce FCR of wheat. The aim of this study was to analyze whether inhibitory Streptomyces isolates affect FCR of wheat and reduce root and stem base colonization by Fusarium culmorum. We enriched sterilized potting soil with spore suspensions of two Streptomyces isolates, inoculated the soil with F. culmorum-colonized wheat straw, and planted pre-germinated wheat seedlings. At 4 weeks, F. culmorum-inoculated plants had significant FCR symptoms on roots and showed reduced fresh weight of roots and above-ground plant biomass compared with the non-inoculated controls. Enrichment of soil with an inhibitory Streptomyces isolate reduced F. culmorum DNA in roots and stem bases by 75% compared with inoculation with F. culmorum alone. Interestingly, co-inoculation of F. culmorum with a non-inhibitory Streptomyces isolate led to the highest levels F. culmorum DNA in stem base tissue and greatest Streptomyces densities (CFU per g of soil) in the rhizosphere. In vitro assays revealed that F. culmorum showed a strong inhibitory activity against the pathogen-inhibitory Streptomyces isolate but not against the non-inhibitory isolate. In vitro tests with a larger set of 17 Streptomyces and five Fusarium spp. isolates revealed that there was little variation among Fusarium spp. isolates in capacities to inhibit the collection of Streptomyces isolates. In contrast, the sensitivity to inhibition by pathogenic Fusarium spp. isolates varied widely among Streptomyces isolates. The results of this study suggest the potential of Streptomyces isolates for biocontrol of FCR of wheat, while highlighting the specificity of Streptomyces−Fusarium interactions. Broader understanding of the variation in susceptibility within Fusarium spp. populations to Streptomyces inhibition and vice versa are needed to advance the potential for successful biological control.

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Synthesis of Indoleacetic acid, Gibberellic Acid and ACC-Deaminase by Mortierella Strains Promote Winter Wheat Seedlings Growth under Different Conditions

10.20944/preprints201809.0298.v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Ewa Ozimek ◽

Jolanta Jaroszuk-Ściseł ◽

Justyna Bohacz ◽

Teresa Korniłłowicz-Kowalska ◽

Renata Tyśkiewicz ◽

...

Keyword(s):

Gibberellic Acid ◽

Winter Wheat ◽

Indoleacetic Acid ◽

Acc Deaminase ◽

Its Region ◽

Temperate Climate ◽

Fresh Weight ◽

Promoting Effect ◽

Wheat Seedlings ◽

Shoot Fresh Weight

The endogenous pool of phytoregulators in plant tissues supplied with microbial secondary metabolites may be crucial for the development of winter wheat seedlings during cool springs. Phytohormones may be synthesized by psychrotrophic microorganisms in lower temperatures occurring in temperate climate. Two fungal isolates from the Spitzbergen soils after the microscopic observations and ITS region molecular characterization were identified as Mortierella antarctica (MA DEM 7) and Mortierella verticillata (MV DEM32). To study the synthesis of indoleacetic acid (IAA) and gibberellic acid (GA) Mortierella strains were grown on media supplemented with precursors of phytohormones (tryptophan or methionine) at 9, 15 and 20 °C for 9 days. The highest amount of IAA synthesis was observed in MV DEM 32 9-day culture at 15 °C with 1.5 mM of tryptophan. At the same temperature the significant promoting effect (about 40% root and shoot fresh weight) of this strain on seedlings was observed. However, only MA DEM 7 had the ACC-deaminase activity with the highest efficiency in 9 °C and at this temperature synthesized IAA without tryptophan also at the same conditions the strain confirmed the strong promoting effect (about 40% root and 24% shoot fresh weight) on seedlings. Both strains synthesized GA in all tested terms and temperatures. Tested Mortierella strains had some important traits to consider them as microbial biofertilizers component improving plant growth in difficult temperate climate. 

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Identification of Putative Virulence Genes by DNA Methylation Studies in the Cereal Pathogen Fusarium graminearum

Cells ◽

10.3390/cells10051192 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1192

Author(s):

Francesco Tini ◽

Giovanni Beccari ◽

Gianpiero Marconi ◽

Andrea Porceddu ◽

Micheal Sulyok ◽

...

Keyword(s):

Dna Methylation ◽

Fusarium Graminearum ◽

Environmental Changes ◽

Virulent Strain ◽

Fungal Virulence ◽

Wheat Seedlings ◽

Wide Range ◽

Conidia Production ◽

Natural Hosts

DNA methylation mediates organisms’ adaptations to environmental changes in a wide range of species. We investigated if a such a strategy is also adopted by Fusarium graminearum in regulating virulence toward its natural hosts. A virulent strain of this fungus was consecutively sub-cultured for 50 times (once a week) on potato dextrose agar. To assess the effect of subculturing on virulence, wheat seedlings and heads (cv. A416) were inoculated with subcultures (SC) 1, 23, and 50. SC50 was also used to re-infect (three times) wheat heads (SC50×3) to restore virulence. In vitro conidia production, colonies growth and secondary metabolites production were also determined for SC1, SC23, SC50, and SC50×3. Seedling stem base and head assays revealed a virulence decline of all subcultures, whereas virulence was restored in SC50×3. The same trend was observed in conidia production. The DNA isolated from SC50 and SC50×3 was subject to a methylation content-sensitive enzyme and double-digest, restriction-site-associated DNA technique (ddRAD-MCSeEd). DNA methylation analysis indicated 1024 genes, whose methylation levels changed in response to the inoculation on a healthy host after subculturing. Several of these genes are already known to be involved in virulence by functional analysis. These results demonstrate that the physiological shifts following sub-culturing have an impact on genomic DNA methylation levels and suggest that the ddRAD-MCSeEd approach can be an important tool for detecting genes potentially related to fungal virulence.

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Preliminary Study on Pasta Samples Characterized in Antioxidant Compounds and Their Biological Activity on Kidney Cells

Nutrients ◽

10.3390/nu13041131 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1131 ◽

Cited By ~ 1

Author(s):

Federico Di Marco ◽

Francesco Trevisani ◽

Pamela Vignolini ◽

Silvia Urciuoli ◽

Andrea Salonia ◽

...

Keyword(s):

Indoleacetic Acid ◽

Antioxidant Properties ◽

Antioxidant Compounds ◽

Kidney Cells ◽

Hek 293 ◽

293 Cells ◽

High Concentrations ◽

Β Carotene ◽

Egg Pasta

Pasta is one of the basic foods of the Mediterranean diet and for this reason it was chosen for this study to evaluate its antioxidant properties. Three types of pasta were selected: buckwheat, rye and egg pasta. Qualitative–quantitative characterization analyses were carried out by HPLC-DAD to identify antioxidant compounds. The data showed the presence of carotenoids such as lutein and polyphenols such as indoleacetic acid, (carotenoids from 0.08 to 0.16 mg/100 g, polyphenols from 3.7 to 7.4 mg/100 g). To assess the effect of the detected metabolites, in vitro experimentation was carried out on kidney cells models: HEK-293 and MDCK. Standards of β-carotene, indoleacetic acid and caffeic acid, hydroalcoholic and carotenoid-enriched extracts from samples of pasta were tested in presence of antioxidant agent to determine viability variations. β-carotene and indoleacetic acid standards exerted a protective effect on HEK-293 cells while no effect was detected on MDCK. The concentrations tested are likely in the range of those reached in body after the consumption of a standard pasta meal. Carotenoid-enriched extracts and hydroalcoholic extracts showed different effects, observing rescues for rye pasta hydroalcoholic extract and buckwheat pasta carotenoid-enriched extract, while egg pasta showed milder dose depending effects assuming pro-oxidant behavior at high concentrations. The preliminary results suggest behaviors to be traced back to the whole phytocomplexes respect to single molecules and need further investigations.

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Effects of Antagonists on Mycotoxins of Seedborne Fusarium spp. in Sweet Corn

Toxins ◽

10.3390/toxins11080438 ◽

2019 ◽

Vol 11 (8) ◽

pp. 438

Author(s):

Mary E. Ridout ◽

Bruce Godfrey ◽

George Newcombe

Keyword(s):

Sweet Corn ◽

Fusarium Species ◽

Fusarium Mycotoxins ◽

Fusarium Spp ◽

Corn Seed ◽

Pichia Membranifaciens ◽

Mature Seeds ◽

F1 Cross

Fusarium species coexist as toxigenic, systemic pathogens in sweet corn seed production in southwestern Idaho, USA. We hypothesized that fungal antagonists of seedborne Fusarium would differentially alter production of Fusarium mycotoxins directly and/or systemically. We challenged the Fusarium complex by in vitro antagonism trials and in situ silk and seed inoculations with fungal antagonists. Fungal antagonists reduced growth and sporulation of Fusarium species in vitro from 40.5% to as much as 100%. Pichia membranifaciens and Penicillium griseolum reduced fumonisin production by F. verticillioides by 73% and 49%, respectively, while P. membranifaciens and a novel Penicillium sp. (WPT) reduced fumonisins by F. proliferatum 56% and 78%, respectively. In situ, pre-planting inoculation of seeds with Penicillium WPT systemically increased fumonisins in the resulting crop. Morchella snyderi applied to silks of an F1 cross systemically reduced deoxynivalenol by 47% in mature seeds of the F2. Antagonists failed to suppress Fusarium in mature kernels following silk inoculations, although the ratio of F. verticillioides to total Fusarium double with some inoculants. Fusarium mycotoxin concentrations in sweet corn seed change systemically, as well as locally, in response to the presence of fungal antagonists, although in Fusarium presence in situ was not changed.

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