Suppression Of Fungal Diseases Research Articles

POTENTIAL OF P. AERUGINOSA CD6C AS ENVIRONMENT FRIENDLY BIO-FUNGICIDE

The current study was conducted at Microbiology Laboratory, Auriga Group of Companies, Lahore duing 2019, aimed for screening and isolating a biocontrol agent that inhibits Macrophomina phaseolina (M. phaseolina) and Fusarium incarnatum (F. incarnatum) growth by reducing disease incidence and increases maize agronomic performance. A plate culture assay was used to screen biocontrol agent for fungal pathogens such as M. phaseolina and F. incarnatum responsible for charcoal foot rot and stalk rot. Among 37 isolates, CD6C isolated from press mud, demonstrated a substantial antifungal potential. The 16S rRNA sequence analysis showed 100% similarity between CD6C and Pseudomonas aeruginosa. The growth inhibition % during plate culture assay for M. phaseolina and F. incarnatum was 46.5 + 1.9 and 49.8 + 1.1, respectively. The supernatant also had the best antifungal activity against charcoal rots caused by M. phaseolina in comparison to the control during the pot experiment. P. aeruginosa CD6C treatment showed a decline in maize foot rot caused by M. phaseolina. Research findings showed that P. aeruginosa CD6C could impede M. phaseolina growth and exacerbate maize plant growth parameters. The data support discovering more antifungal compounds from P. aeruginosa CD6C, which can lead to competent and successful pathogen biocontrol treatment. Moreover, study suggested that P. aeruginosa CD6C was found to be auspicious for maize plant and should be promoted for plant growth enhancement and suppression of fungal diseases by scaling down chemical pesticides for pollution control.

Fungal disease suppression and growth promotion potential of endophytic bacteria from ethnomedicinal plants.

103 bacterial isolates obtained from 8 ethnomedicinal plants in Manipur, India were studied for antifungal and plant growth promoting (PGP) activities. Forty-six (46), out of 62 antifungal isolates, showed potent activities against R. solani. Since R. solani (RS), a sheath blight pathogen, threatens rice yields worldwide, the present study was aimed at discovering promising bioinoculants with anti-RS and PGP potential on rice. Twenty-nine (29) endophytic isolates exhibiting promising anti-RS and PGP activities were subjected to seed vigor assays on rice (var. Jatra) and 16 were found to enhance rice seedling vigour by 70% or more over the control. Four (4) strains, Streptomyces sp. (AcRz21), Alkalihalobacillus sp. (PtL11), Bacillus sp. (TgIb5), and Priestia sp. (TgIb12) with the highest vigor indices were studied for growth promotion of rice in field conditions under pathogen-challenged and pathogen-free conditions. These bioactive strains were able to significantly enhance root and shoot biomass and reduce lesion heights caused by R. solani.

Biomolecular corona formation on CuO nanoparticles in plant xylem fluid

CuO nanoparticles selectively remove proteins from Cucurbita pepo (pumpkin) xylem to form a nanoparticle corona.

Chitosan-Coated Mesoporous Silica Nanoparticle Treatment of Citrullus lanatus (Watermelon): Enhanced Fungal Disease Suppression and Modulated Expression of Stress-Related Genes

This work assesses the potential of mesoporous silica nanoparticles with or without a chitosan coating to suppress Fusarium wilt (Fusarium oxysporum f. sp. niveum) in watermelon (Citrullus lanatus)...

Protecting plants from the inside out

Plant Microbiota Some soils show a remarkable ability to suppress disease caused by plant pathogens, an ability that is attributed to plant-associated microbiota. Carrion et al. investigated the role of endophytes, the intimate microbial community found within roots, in fungal disease suppression (see the Perspective by Tringe). The wilt fungus Rhizoctonia solani infects sugar beets, whereupon transcriptional analysis shows that several bacterial endophyte species activate biosynthetic gene clusters to cause disease suppression. These organisms produce antifungal effectors, including enzymes that can digest fungal cell walls, and secondary metabolites, including phenazines, polyketides, and siderophores, which may contribute to the antifungal phenotype. Science , this issue p. [606][1]; see also p. [568][2] [1]: /lookup/doi/10.1126/science.aaw9285 [2]: /lookup/doi/10.1126/science.aaz5619

Differential impacts of brassicaceous and nonbrassicaceous oilseed meals on soil bacterial and fungal communities

Demand for alternative fuels has sparked renewed interest in the production of biodiesel from oil-rich seeds. Oilseed meals are a byproduct of this process, and given their relatively high nutrient content, land application represents a potential value-added use. In this microcosm-based study, soil microbial community responses to amendments of a glucosinolate-containing brassicaceous oilseed meal (Brassica juncea, mustard), a non-glucosinolate-containing, nonbrassicaceous oilseed meal (Linum usitatissimum, flax), and a nonoilseed biomass (Sorghum bicolor) were characterized using a 28-day time series of replicated 16S rRNA gene and fungal ITS gene sequence libraries. We hypothesized that biomass type and glucosinolate content would alter community composition but that effects would diminish over time. Distinct separation occurred by amendment type, with mustard inducing large increases in the abundance of bacterial taxa associated with fungal disease suppression (e.g. Bacillus, Pseudomonas, and Streptomyces spp.). Dramatic shifts were seen among the fungi, too, with phylotype richness decreasing by >60% following mustard addition. Changes in bacterial and fungal community composition were rapid, and distinct community types persisted throughout the study. Oilseed amendment, and mustard in particular, has the potential to alter soil microbial community structure substantially, and such changes are likely to be important in the context of ecosystem health.

Fungal communities associated with durum wheat production system: A characterization by growth stage, plant organ and preceding crop

Fungal diversity in soil and durum wheat was studied in relation to durum, oilseed and pulse preceding crops, durum growth stages and plant organs. Fungi isolated from soil and plant samples were classified in 258 operational taxonomical units (OTUs) followed by the PCR amplification and sequencing of the internal transcribed spacer (ITS) rDNA and elongation factor EF-1 alpha gene. Most of the 46 identified fungal species belong to Ascomycota and few isolates to Basidiomycota and Zygomycota phyla. Penicillium, Fusarium and Geomyces spp. were abundant throughout growth stages and plant organs. Seventeen species were potential pathogens on durum wheat and, among them, Fusarium taxa are the most abundant. Other pathogenic taxa recovered belong to Pyrenophora, Alternaria, Nigrospora, Microdochium, Bipolaris, Phaeosphaeria, Arthrinium and Cladosporium taxa. Crop rotation significantly impacted the dominance of two fungal pathogens: Bipolaris sorokiniana (teleomorph: Cochliobolus sativus) was less abundant in durum following a year of pea, whereas Fusarium torulosum was less abundant in durum following canola crops. Principal component analysis combined with persistence index of spatio-temporal species distribution showed that the occurrence of fungi such as Acremonium, Chaetomium, Epicoccum, Kabatiella, Penicillium and Trichoderma were negatively related to the Fusarium and Bipolaris isolates, and therefore, they may be potential antagonists or biocontrol candidates against both pathogens. This study provides a basis for screening beneficial fungal species associated to durum wheat in wheat-based cropping systems of the Canadian Prairies. Assessing the biodiversity is crucial for the development of effective integrated management strategies, including biocontrol agents for the suppression of fungal diseases.

Bacterial siderophores: Structure elucidation, 2D 1H and 13C NMR assignments of pyoverdins produced by Pseudomonas fluorescens CHAO

The structure of two pyoverdins produced in iron-deficient cultures of Pseudomonas fluorescens CHAO, a bacterium responsible for suppression of fungal diseases in plant roots, was elucidated using essentially FAB-MS and homonuclear and heteronuclear 2D NMR techniques. It is a partly cyclic chromopeptide: chromophore-Asp-OHOrn-Lys- cyclo-(Thr-Ala-Ala-OHOrn-Lys forming a sixteen-membered lactone ring.

A Possible Role for Ferrous Complexes in Fungal Disease Suppression: Glume Blotch and Net Blotch of Cereals

AbstractGermination of spores of Septoria nodorum and Pyrenophora teres was inhibited and germ‐tube growth in germinated spores was reduced b y ferrous ions complexed with a number of cheiating agents. No such inhibition was observed with ferric complexes and none of the chelating agents in the desferri form was toxic to the fungi. The germination mechanism in spores suspended in ferrous‐2,3‐dihydroxybenzoic acid (Fe11‐DHBA) for 24 h could not subsequently be released to any great extent by incubation with ethylenediamjne‐di (o‐hydroxyphenyl‐acetic acid) (EDDHA).Lesion development by the fungi in the presence of ferrous complexes on detached leaves of host plants was almost totally suppressed, but compounds which preferentially chelate ferric ions, used in the desferri form significantly stimulated lesion development by S. nodorum on wheat leaves. Cermination, appressorium formation and lesion development on leaves of host plants were also significantly reduced by Fe11‐DHBA when plants were sprayed to run‐off up to 5 days prior to inoculation.Disease development and subsequent 1000 grain weight loss were reduced by approximately 50 percent in wheat and barley plants when the flag leaves were treated with Fe11‐DHBA (5 × 10−4 M) prior to inoculation with S. nodorum and P. teres respectively, compared with inoculated, untreated plants.