scholarly journals Antagonistic Activity of Trichoderma spp. Against Fusarium oxysporum in Rhizosphere of Radix pseudostellariae Triggers the Expression of Host Defense Genes and Improves Its Growth Under Long-Term Monoculture System

2021 ◽  
Vol 12 ◽  
Author(s):  
Jun Chen ◽  
Liuting Zhou ◽  
Israr Ud Din ◽  
Yasir Arafat ◽  
Qian Li ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Fungal Pathogens ◽  
Pathogenic Fungi ◽  
Inhibitory Effect ◽  
Pcr Analysis ◽  
Defense Genes ◽  
Trichoderma Spp ◽  
Antagonistic Microorganisms

Under consecutive monoculture, the abundance of pathogenic fungi, such as Fusarium oxysporum in the rhizosphere of Radix pseudostellariae, negatively affects the yield and quality of the plant. Therefore, it is pertinent to explore the role of antagonistic fungi for the management of fungal pathogens such as F. oxysporum. Our PCR-denatured gradient gel electrophoresis (DGGE) results revealed that the diversity of Trichoderma spp. was significantly declined due to extended monoculture. Similarly, quantitative PCR analysis showed a decline in Trichoderma spp., whereas a significant increase was observed in F. oxysporum. Furthermore, seven Trichoderma isolates from the R. pseudostellariae rhizosphere were identified and evaluated in vitro for their potentiality to antagonize F. oxysporum. The highest and lowest percentage of inhibition (PI) observed among these isolates were 47.91 and 16.67%, respectively. In in vivo assays, the R. pseudostellariae treated with four Trichoderma isolates, having PI > 30%, was used to evaluate the biocontrol efficiency against F. oxysporum in which T. harzianum ZC51 enhanced the growth of the plant without displaying any disease symptoms. Furthermore, the expression of eight defense-related genes of R. pseudostellariae in response to a combination of F. oxysporum and T. harzianum ZC51 treatment was checked, and most of these defense genes were found to be upregulated. In conclusion, this study reveals that the extended monoculture of R. pseudostellariae could alter the Trichoderma communities in the plant rhizosphere leading to relatively low level of antagonistic microorganisms. However, T. harzianum ZC51 could inhibit the pathogenic F. oxysporum and induce the expression of R. pseudostellariae defense genes. Hence, T. harzianum ZC51 improves the plant resistance and reduces the growth inhibitory effect of consecutive monoculture problem.

scholarly journals Self-Inhibitory Activity of Trichoderma Soluble Metabolites and Their Antifungal Effects on Fusarium oxysporum

2020 ◽  
Vol 6 (3) ◽  
pp. 176
Author(s):  
Samuel Álvarez-García ◽  
Sara Mayo-Prieto ◽  
Santiago Gutiérrez ◽  
Pedro Antonio Casquero
Keyword(s):  
Fusarium Oxysporum ◽  
Inhibitory Activity ◽  
Inhibitory Effects ◽  
Trichoderma Spp ◽  
Macroscopic Structure ◽  
Biocontrol Activity ◽  
Microbial Strains ◽  
Phytopathogenic Microorganisms

Self-inhibitory processes are a common feature shared by different organisms. One of the main mechanisms involved in these interactions regarding microorganisms is the release of toxic diffusible substances into the environment. These metabolites can exert both antimicrobial effects against other organisms as well as self-inhibitory ones. The in vitro evaluation of these effects against other organisms has been widely used to identify potential biocontrol agents against phytopathogenic microorganisms. In the present study, we performed membrane assays to compare the self-inhibitory effects of soluble metabolites produced by several Trichoderma isolates and their antifungal activity against a phytopathogenic strain of Fusarium oxysporum. The results demonstrated that Trichoderma spp. present a high self-inhibitory activity in vitro, being affected in both their growth rate and the macroscopic structure of their colonies. These effects were highly similar to those exerted against F. oxysporum in the same conditions, showing no significant differences in most cases. Consequently, membrane assays may not be very informative by themselves to assess putative biocontrol capabilities. Therefore, different methods, or a combination of antifungal and self-inhibitory experiments, could be a better approach to evaluate the potential biocontrol activity of microbial strains in order to pre-select them for further in vivo trials.

scholarly journals Effects of Hsp90 Inhibitor Ganetespib on Inhibition of Azole-Resistant Candida albicans

2021 ◽  
Vol 12 ◽  
Author(s):  
Rui Yuan ◽  
Jie Tu ◽  
Chunquan Sheng ◽  
Xi Chen ◽  
Na Liu
Keyword(s):  
Drug Resistance ◽  
Candida Albicans ◽  
Biofilm Formation ◽  
Efflux Pump ◽  
Inhibitory Effect ◽  
Hsp90 Inhibitor ◽  
Pcr Analysis ◽  
Fungal Hypha

Candida albicans is the most common fungal pathogen. Recently, drug resistance of C. albicans is increasingly severe. Hsp90 is a promising antifungal target to overcome this problem. To evaluate the effects of Hsp90 inhibitor ganetespib on the inhibition of azole-resistant C. albicans, the microdilution checkerboard method was used to measure the in vitro synergistic efficacy of ganetespib. The XTT/menadione reduction assay, microscopic observation, and Rh6G efflux assay were established to investigate the effects of ganetespib on azole-resistant C. albicans biofilm formation, filamentation, and efflux pump. Real-time RT-PCR analysis was employed to clarify the mechanism of antagonizing drug resistance. The in vivo antifungal efficacy of ganetespib was determined by the infectious model of azole-resistant C. albicans. Ganetespib showed an excellent synergistic antifungal activity in vitro and significantly inhibited the fungal biofilm formation, whereas it had no inhibitory effect on fungal hypha formation. Expression of azole-targeting enzyme gene ERG11 and efflux pump genes CDR1, CDR2, and MDR1 was significantly down-regulated when ganetespib was used in combination with FLC. In a mouse model infected with FLC-resistant C. albicans, the combination of ganetespib and FLC effectively reversed the FLC resistance and significantly decreased the kidney fungal load of mouse.

scholarly journals Fusarium oxysporum (F221-B) as biocontrol agent against plant pathogenic fungi in vitro and in hydroponics

2017 ◽  
Vol 53 (No. 2) ◽  
pp. 85-95 ◽  
Author(s):  
Thongkamngam Titi ◽  
Jaenaksorn Tanimnun
Keyword(s):  
Fusarium Oxysporum ◽  
Fungal Pathogens ◽  
Biocontrol Agent ◽  
Disease Incidence ◽  
Pathogenic Fungi ◽  
Curvularia Lunata ◽  
Plant Growth Promoting ◽  
Healthy Control ◽  
Further Development

Efficacy of non-pathogenic Fusarium oxysporum (F221-B) was assessed as a possible biocontrol agent against fungal pathogens, namely Curvularia lunata (C11, C12), F. semitectum (F113), F. oxysporum f.sp. lactucae (F221-R, F442-G), Rhizoctonia solani (R11, R12), Rhizoctonia sp. (R111, R112, R113) in vitro, while F221-B showed a moderate ability to inhibit the mycelial growth of tested fungi about 36–56%. Then, F221-B was further evaluated for its ability of controlling lettuce root rot and wilt caused by F442-G in hydroponics. It was revealed that F221-B reduced disease incidence and severity about 60–80% compared to the inoculated control and significantly promoted the growth of 3 lettuce varieties. Interestingly, using only F221-B gave the significantly highest fresh weight (twice over the healthy control). Conclusively, this study provides an important suggestion for further development of F221-B since it showed the ability of biocontrol agent and plant growth promoting fungus.

scholarly journals The effect of chitosan on limitation of growth and development of some pathogenic fungi for ornamental plants

2013 ◽  
Vol 54 (1) ◽  
pp. 17-29 ◽  
Author(s):  
Alicja Saniewska
Keyword(s):  
Fusarium Oxysporum ◽  
Inhibitory Action ◽  
Marked Effect ◽  
Ornamental Plants ◽  
Pathogenic Fungi ◽  
Inhibitory Effect ◽  
Crab Shell ◽  
Necrotic Spots ◽  
Tulip Bulbs

The inhibitory effect of crab-shell chitosan, medium (200-800 cps) and high molecular weight ( 800-2000 cps) (purchased from Sigma-Aldrich Chemicals) toward <i>Alternaria alternata, Botrytis tulipae, Fiisarium oxysporum</i> f. sp. <i>callistephi, Fusarium oxysporum</i> f. sp. <i>tulipae, Phoma narcissi</i> and <i> Phoma poolensis</i> was evaluated <i>in vitro</i> and in <i>vivo</i>. The chitosan evidently inhibited in vitro growth of all tested pathogens, with a marked effect at higher concentrations above 200 μg/cm<sup>3</sup>. Chitosan at a concentration of 1,25; 2,5 and 5,0 mg/cm<sup>3</sup> didn't have inhibitory action in appearance of fungi growth on naturally contaminated <i>Callistephus chinensis</i> seeds. At the same concentrations, chitosan applied as bulb scales dressing of <i>Hymenocallis narcissiflora</i> bulbs, before inoculation or after inoculation with <i>Phoma narcissi</i>, inhibited the development of necrotic spots on scales. Chitosan used preventively or curatively at a concentrations of 1,25; 2,5 and 5,0 mg/cm<sup>3</sup> indicated inhibitory effect on development of <i>Fusarium oxysporum</i> f. sp. <i>tulipae</i> on tulip bulbs. Chitosan at a concentration of 10 mg/cm<sup>3</sup> applied preventively (first spray 12th June) was very effective in the control of <i>Puccinia antirrhini</i> on snapdragon in the field. The strongest inhibitory effect was observed on snapdragon treated 8 times at week intervals.

scholarly journals Effect of Commercial Cyanobacteria Products on the Growth and Antagonistic Ability of Some Bioagents under Laboratory Conditions

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Nehal S. El-Mougy ◽  
Mokhtar M. Abdel-Kader
Keyword(s):  
Growth Medium ◽  
Linear Growth ◽  
Fungal Growth ◽  
Pathogenic Fungi ◽  
Inhibitory Effect ◽  
Green Algal ◽  
Soil Borne Pathogens ◽  
Antagonistic Microorganisms ◽  
Soil Borne Fungi

Evaluation of the efficacy of blue-green algal compounds against the growth of either pathogenic or antagonistic microorganisms as well as their effect on the antagonistic ability of bioagents was studied underin vitroconditions. The present study was undertaken to explore the inhibitory effect of commercial algal compounds, Weed-Max and Oligo-Mix, against some soil-borne pathogens. In growth medium supplemented with these algal compounds, the linear growth of pathogenic fungi decreased by increasing tested concentrations of the two algal compounds. Complete reduction in pathogenic fungal growth was observed at 2% of both Weed-Max and Oligo-Mix. Gradual significant reduction in the pathogenic fungal growth was caused by the two bioagents and by increasing the concentrations of algal compounds Weed-Max and Oligo-Mix. The present work showed that commercial algal compounds, Weed-Max and Oligo-Mix, have potential for the suppression of soil-borne fungi and enhance the antagonistic ability of fungal, bacterial, and yeast bio-agents.

scholarly journals Herbal NF-κB Inhibitors Sensitize Rituximab-Resistant B Lymphoma Cells to Complement-Mediated Cytolysis

2021 ◽  
Vol 11 ◽  
Author(s):  
Xiaowen Ge ◽  
Yiqun Du ◽  
Jianfeng Chen ◽  
Na Zhu ◽  
Jiamei Yao ◽  
...  
Keyword(s):  
Inhibitory Effect ◽  
Pcr Analysis ◽  
Immunoblotting Analysis ◽  
B Lymphoma Cells ◽  
Complement Dependent Cytotoxicity ◽  
Highly Correlated ◽  
Cd59 Expression ◽  
Resistant Cells

BackgroundDrug resistance remains a serious challenge to rituximab therapy in B-NHL (B cell non-Hodgkin’s lymphoma). CDC (complement-dependent cytotoxicity) has been proposed as a major antitumor mechanism of rituximab, and direct abrogation of CD59 function partially restores rituximab sensitivity with high efficacy. However, universal blockade of CD59 may have deleterious effects on normal cells. Sp1 regulates constitutive CD59 expression, whereas NF-κB and CREB regulate inducible CD59 expression.MethodsImmunohistochemistry (IHC) assay was used to detect the expression levels of CD59 and other related molecules. Quantitative Real-time PCR (RT-PCR) analysis was used to explore the levels of transcripts in the original and resistant cells. We chose LY8 cells to test the effects of NF-κB and CBP/p300 inhibition on CD59 expression using flow cytometry (FACS). Immunoblotting analysis was employed to detect the effects of curcumin and POH. The in vitro and in vivo experiments were used to evaluate the toxicity and combined inhibitory effect on tumor cells of curcumin and POH.ResultsWe demonstrated that herbal (curcumin and perillyl alcohol) blockade of NF-κB specifically suppresses the expression of inducible CD59 but not CD20, thus sensitizing resistant cells to rituximab-mediated CDC. Moreover, activation of NF-κB and CREB is highly correlated with CD59 expression in B-NHL tissues.ConclusionsOur findings suggest the potential of CD59 expression as a predictor of therapeutic efficacy of NF-κB inhibitors in clinical application as well as the rationality of a NF-κB inhibitor-rituximab regimen in B-NHL therapy.

scholarly journals PEMANFAATAN BIOFUNGISIDA BERBAHAN AKTIF Trichoderma spp. UNTUK PENGENDALIAN PENYAKIT BUSUK BUAH KAKAO

2016 ◽  
Vol 3 (1) ◽  
pp. 28
Author(s):  
Winda Nawfetrias ◽  
Eka Nurhangga ◽  
Sutardjo .
Keyword(s):  
Active Ingredient ◽  
Low Cost ◽  
Pathogenic Fungi ◽  
Culture Method ◽  
Dual Culture ◽  
Trichoderma Spp ◽  
Cocoa Production ◽  
Black Pod

Cocoa black pod rot is caused by pathogenic fungi, Phytophtora palmivora, which decrease the cocoa production up to 90%. The use of biological control agents, Trichoderma spp., is one of the promising P. palmivora controllers since it is low-cost, easily found and safe for the environment. The aims of this research were to understand the compatibility, antagonistic and effectiveness of biofungicide containing active ingredient of Trichoderma spp. against P. palmivora in vitro and to test the effective concentration of biofungicide containing active ingredient of T. asperellum to control P. palmivora in vitro and in vivo. T. asperellum, T. harzianum, and T. viride were grown together on PDA medium to test their compatibility. Antagonistic and effectiveness test of Trichoderma spp. against P. palmivora were tested using the in vitro dual culture method. The effectiveness of T. asperellum biofungicide was tested in vivo on cocoa pot. Compatibility test showed that all three species were compatible and the best effectiveness showed by the combination of T. asperellum and T. viride. The result also showed that T. asperellum biofungicide had an ability to inhibit P. palmivora.   Keywords: Trichoderma spp., effectivity, compatibility, antagonistic, biofungicide  ABSTRAKPenyakit busuk buah kakao disebabkan cendawan patogen Phytophtora palmivora, yang dapat menurunkan produksi kakao sampai 90%. Penggunaan agensia pengendali hayati (APH), Trichoderma spp., merupakan salah satu pengendalian P. palmivora yang menjanjikan karena murah, mudah didapat dan aman terhadap lingkungan. Penelitian ini bertujuan mengetahui kesesuaian, antagonistik, dan efektivitas biofungisida berbahan aktif Trichoderma spp. secara in vitro. Di samping itu juga bertujuan mengetahui konsentrasi efektif biofungisida berbahan aktif T. asperellum untuk mengendalikan P. palmivora secara in vitro dan in vivo. T. asperellum, T. harzianum, dan T. viride, ditumbuhkan bersama pada media PDA untuk mengetahui kesesuaian antarspesies. Antagonistik dan efektivitas Trichoderma spp. terhadap P. palmivora secara in vitro diuji menggunakan metode dual culture. Biofungisida berbahan aktif T. asperellum diuji efektivitasnya secara in vivo pada buah kakao. Hasil uji kesesuaian menunjukkan bahwa ketiga spesies yang diuji berkesesuaian dan efektifitas terbaik ditunjukkan pada kombinasi T. asperellum dan T. viride. Hasil penelitian juga menunjukkan bahwa biofungisida berbahan aktif T. asperellum dengan konsentrasi tertinggi terbukti dapat menghambat pertumbuhan P. palmivora.Kata kunci: Trichoderma spp., efektivitas, kesesuaian, antagonis, biofungisida

scholarly journals AtWRKY75 positively regulates jasmonate-mediated plant defense to necrotrophic fungal pathogens

2020 ◽  
Author(s):  
Ligang Chen ◽  
Liping Zhang ◽  
Shengyuan Xiang ◽  
Yanli Chen ◽  
Haiyan Zhang ◽  
...  
Keyword(s):  
Plant Defense ◽  
Signaling Pathway ◽  
Defense Response ◽  
Fungal Pathogens ◽  
Defense Responses ◽  
Alternaria Brassicicola ◽  
Pcr Analysis ◽  
Agronomic Crops

Abstract Necrotrophic fungi cause devastating diseases in both horticultural and agronomic crops, but our understanding of plant defense responses against these pathogens is still limited. In this study, we demonstrated that AtWRKY75 positively regulates the jasmonate (JA)-mediated plant defense against necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola and also affects plants’ sensitivity to JA-inhibited seed germination and root growth. Quantitative RT-PCR analysis indicated that the expression of several JA-associated genes, such as ORA59 and PDF1.2, was significantly reduced in wrky75 mutants and significantly enhanced in 35S:WRKY75 transgenic plants. Immunoprecipitation assays revealed that WRKY75 directly binds to ORA59 promoters and represses its transcription. In vivo and in vitro experiments suggested that WRKY75 interacts with several JASMONATE ZIM-domain proteins, which are repressors of the JA signaling pathway. We determined that JAZ8 represses the transcriptional function of WRKY75, thereby attenuating the expression of its regulon. Consistent with this finding, overexpression of JAZ8 repressed plant defense response to B. cinerea. Taken together, our study provides evidence that WRKY75 functions as a critical component of the JA-mediated signaling pathway to positively regulate Arabidopsis defense response to necrotrophic pathogens.

scholarly journals The Constitutive Endopolygalacturonase TvPG2 Regulates the Induction of Plant Systemic Resistance by Trichoderma virens

2017 ◽  
Vol 107 (5) ◽  
pp. 537-544 ◽  
Author(s):  
Sabrina Sarrocco ◽  
Fabiola Matarese ◽  
Riccardo Baroncelli ◽  
Giovanni Vannacci ◽  
Verena Seidl-Seiboth ◽  
...  
Keyword(s):  
Pathogenic Fungi ◽  
Phytopathogenic Fungi ◽  
Plant Roots ◽  
Systemic Resistance ◽  
Trichoderma Spp ◽  
Opportunistic Fungi ◽  
Beneficial Effects ◽  
Tomato Roots

Trichoderma spp. are opportunistic fungi some of which are commonly present in the rhizosphere. Several species, such as T. virens, are also efficient biocontrol agents against phytopathogenic fungi and exert beneficial effects on plants. These effects are the consequence of interactions between Trichoderma and plant roots, which trigger enhanced plant growth and induce plant resistance. We have previously shown that T. virens I10 expresses two endopolygalacturonase genes, tvpg1 and tvpg2, during the interaction with plant roots; tvpg1 is inducible while tvpg2 is constitutively transcribed. Using the same system, the tomato polygalacturonase-inhibitor gene Lepgip1 was induced at the same time as tvpg1. Here we show by gene disruption that TvPG2 performs a regulatory role on the inducible tvpg1 gene and in triggering the plant immune response. A tvpg2-knockout strain fails to transcribe the inducible tvpg1 gene in neither in vitro in inducing media containing pectin or plant cell walls, nor during the in vivo interaction with tomato roots. Likewise, the in vivo induction of Lepgip1 does not occur, and its defense against the pathogen Botrytis cinerea is significantly reduced. Our data prove the importance of a T. virens constitutively produced endopolygalacturonase in eliciting plant induced systemic resistance against pathogenic fungi.

scholarly journals In Vitro and In Vivo Interactions of TOR Inhibitor AZD8055 and Azoles against Pathogenic Fungi

2022 ◽  
Author(s):  
Yi Sun ◽  
Lihua Tan ◽  
Zhaoqian Yao ◽  
Lujuan Gao ◽  
Ji Yang ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Combination Therapy ◽  
Fungal Pathogens ◽  
Pathogenic Fungi ◽  
Valuable Alternative ◽  
Clinical Challenge

Limited options of antifungals and the emergence of drug resistance in fungal pathogens has been a multifaceted clinical challenge. Combination therapy represents a valuable alternative to antifungal monotherapy.

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