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Christopher R. Thornton - One of the best experts on this subject based on the ideXlab platform.
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Biological control of soil-borne pathogens.
2013Co-Authors: As Romão-dumaresq, Nicholas J. Talbot, Welington Luiz De ,araujo, Christopher R. ThorntonAbstract:(a) Biocontrol of pineapple disease of sugarcane caused by the soil-borne pathogen Ceratocystis Paradoxa. Germination of sugarcane setts was determined in compost infested with the pathogen C. Paradoxa and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured weekly, over a 6 week period. The control consisted of sugarcane setts planted in uninfested compost. Each point is the mean of twelve replicates and percentages were converted to arc sin−1 values for statistical analysis by t-test. Points with different letters are significantly different at 95% confidence level, considering each week separately. (b) Biocontrol of pre-emergence damping-off disease of lettuce caused by the pathogen Sclerotinia sclerotiorum, Germination of lettuce seeds was determined in peat-based microcosms infested with the pathogen S. sclerotiorum and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured 10 days after sowing. The control consisted of lettuce seeds planted in uninfested peat. Each point is the mean of three replicates (each consisting of 25 lettuce seed) and percentages were converted to arc sin−1 values for statistical analysis by Tukey test for comparison of means. Histograms with different letters are significantly different at 99% confidence level. (c) Biocontrol of bean rot caused by the pathogen Rhizoctonia solani. Germination of bean seeds was determined in compost infested with the pathogen R. solani and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured 20 days after sowing. The control consisted of bean seeds planted in uninfested compost. Each point is the mean of six replicates and percentages were converted to arc sin−1 values for statistical analysis by Tukey test for comparison of means. Histograms with different letters are significantly different at 95% confidence level.
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RNA Interference of Endochitinases in the Sugarcane Endophyte Trichoderma virens 223 Reduces Its Fitness as a Biocontrol Agent of Pineapple Disease
PloS one, 2012Co-Authors: As Romão-dumaresq, Nicholas J. Talbot, Welington Luiz De ,araujo, Christopher R. ThorntonAbstract:The sugarcane root endophyte Trichoderma virens 223 holds enormous potential as a sustainable alternative to chemical pesticides in the control of sugarcane diseases. Its efficacy as a biocontrol agent is thought to be associated with its production of chitinase enzymes, including N-acetyl-s-D-glucosaminidases, chitobiosidases and endochitinases. We used targeted gene deletion and RNA-dependent gene silencing strategies to disrupt N-acetyl-s-D-glucosaminidase and endochitinase activities of the fungus, and to determine their roles in the biocontrol of soil-borne plant pathogens. The loss of N-acetyl-s-D-glucosaminidase activities was dispensable for biocontrol of the plurivorous damping-off pathogens Rhizoctonia solani and Sclerotinia sclerotiorum, and of the sugarcane pathogen Ceratocystis Paradoxa, the causal agent of pineapple disease. Similarly, suppression of endochitinase activities had no effect on R. solani and S. sclerotiorum disease control, but had a pronounced effect on the ability of T. virens 223 to control pineapple disease. Our work demonstrates a critical requirement for T. virens 223 endochitinase activity in the biocontrol of C. Paradoxa sugarcane disease, but not for general antagonism of other soil pathogens. This may reflect its lifestyle as a sugarcane root endophyte.
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RNA Interference of Endochitinases in the Sugarcane Endophyte Trichoderma virens 223 Reduces Its Fitness as a Biocontrol Agent of Pineapple Disease
2012Co-Authors: Aline S. Romão-dumaresq, Welington Luiz Araújo, Nicholas J. Talbot, Christopher R. ThorntonAbstract:The sugarcane root endophyte Trichoderma virens 223 holds enormous potential as a sustainable alternative to chemical pesticides in the control of sugarcane diseases. Its efficacy as a biocontrol agent is thought to be associated with its production of chitinase enzymes, including N-acetyl-ß-D-glucosaminidases, chitobiosidases and endochitinases. We used targeted gene deletion and RNA-dependent gene silencing strategies to disrupt N-acetyl-ß-D-glucosaminidase and endochitinase activities of the fungus, and to determine their roles in the biocontrol of soil-borne plant pathogens. The loss of N-acetyl-ß-D-glucosaminidase activities was dispensable for biocontrol of the plurivorous damping-off pathogens Rhizoctonia solani and Sclerotinia sclerotiorum, and of the sugarcane pathogen Ceratocystis Paradoxa, the causal agent of pineapple disease. Similarly, suppression of endochitinase activities had no effect on R. solani and S. sclerotiorum disease control, but had a pronounced effect on the ability of T. virens 223 to control pineapple disease. Our work demonstrates a critical requirement for T. virens 223 endochitinase activity in the biocontrol of C. Paradoxa sugarcane disease, but not fo
As Romão-dumaresq - One of the best experts on this subject based on the ideXlab platform.
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RNA interference of endochitinases in the sugarcane endophyte Trichoderma virens 223 reduces its fitness as a biocontrol agent of pineapple disease
'Public Library of Science (PLoS)', 2013Co-Authors: As Romão-dumaresq, Talbot, Nicholas J., Wl ,de Araújo, Cr ThorntonAbstract:publication-status: PublishedThe sugarcane root endophyte Trichoderma virens 223 holds enormous potential as a sustainable alternative to chemical pesticides in the control of sugarcane diseases. Its efficacy as a biocontrol agent is thought to be associated with its production of chitinase enzymes, including N-acetyl-β-D-glucosaminidases, chitobiosidases and endochitinases. We used targeted gene deletion and RNA-dependent gene silencing strategies to disrupt N-acetyl-β-D-glucosaminidase and endochitinase activities of the fungus, and to determine their roles in the biocontrol of soil-borne plant pathogens. The loss of N-acetyl-β-D-glucosaminidase activities was dispensable for biocontrol of the plurivorous damping-off pathogens Rhizoctonia solani and Sclerotinia sclerotiorum, and of the sugarcane pathogen Ceratocystis Paradoxa, the causal agent of pineapple disease. Similarly, suppression of endochitinase activities had no effect on R. solani and S. sclerotiorum disease control, but had a pronounced effect on the ability of T. virens 223 to control pineapple disease. Our work demonstrates a critical requirement for T. virens 223 endochitinase activity in the biocontrol of C. Paradoxa sugarcane disease, but not for general antagonism of other soil pathogens. This may reflect its lifestyle as a sugarcane root endophyte
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Biological control of soil-borne pathogens.
2013Co-Authors: As Romão-dumaresq, Nicholas J. Talbot, Welington Luiz De ,araujo, Christopher R. ThorntonAbstract:(a) Biocontrol of pineapple disease of sugarcane caused by the soil-borne pathogen Ceratocystis Paradoxa. Germination of sugarcane setts was determined in compost infested with the pathogen C. Paradoxa and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured weekly, over a 6 week period. The control consisted of sugarcane setts planted in uninfested compost. Each point is the mean of twelve replicates and percentages were converted to arc sin−1 values for statistical analysis by t-test. Points with different letters are significantly different at 95% confidence level, considering each week separately. (b) Biocontrol of pre-emergence damping-off disease of lettuce caused by the pathogen Sclerotinia sclerotiorum, Germination of lettuce seeds was determined in peat-based microcosms infested with the pathogen S. sclerotiorum and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured 10 days after sowing. The control consisted of lettuce seeds planted in uninfested peat. Each point is the mean of three replicates (each consisting of 25 lettuce seed) and percentages were converted to arc sin−1 values for statistical analysis by Tukey test for comparison of means. Histograms with different letters are significantly different at 99% confidence level. (c) Biocontrol of bean rot caused by the pathogen Rhizoctonia solani. Germination of bean seeds was determined in compost infested with the pathogen R. solani and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured 20 days after sowing. The control consisted of bean seeds planted in uninfested compost. Each point is the mean of six replicates and percentages were converted to arc sin−1 values for statistical analysis by Tukey test for comparison of means. Histograms with different letters are significantly different at 95% confidence level.
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RNA Interference of Endochitinases in the Sugarcane Endophyte Trichoderma virens 223 Reduces Its Fitness as a Biocontrol Agent of Pineapple Disease
PloS one, 2012Co-Authors: As Romão-dumaresq, Nicholas J. Talbot, Welington Luiz De ,araujo, Christopher R. ThorntonAbstract:The sugarcane root endophyte Trichoderma virens 223 holds enormous potential as a sustainable alternative to chemical pesticides in the control of sugarcane diseases. Its efficacy as a biocontrol agent is thought to be associated with its production of chitinase enzymes, including N-acetyl-s-D-glucosaminidases, chitobiosidases and endochitinases. We used targeted gene deletion and RNA-dependent gene silencing strategies to disrupt N-acetyl-s-D-glucosaminidase and endochitinase activities of the fungus, and to determine their roles in the biocontrol of soil-borne plant pathogens. The loss of N-acetyl-s-D-glucosaminidase activities was dispensable for biocontrol of the plurivorous damping-off pathogens Rhizoctonia solani and Sclerotinia sclerotiorum, and of the sugarcane pathogen Ceratocystis Paradoxa, the causal agent of pineapple disease. Similarly, suppression of endochitinase activities had no effect on R. solani and S. sclerotiorum disease control, but had a pronounced effect on the ability of T. virens 223 to control pineapple disease. Our work demonstrates a critical requirement for T. virens 223 endochitinase activity in the biocontrol of C. Paradoxa sugarcane disease, but not for general antagonism of other soil pathogens. This may reflect its lifestyle as a sugarcane root endophyte.
Emmanuel I. Eziashi - One of the best experts on this subject based on the ideXlab platform.
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insect larva the culture medium for fungi storage
American Journal of Experimental Agriculture, 2013Co-Authors: Emmanuel I. Eziashi, E E Odigie, C. I. Aisagbonhi, E A OruadedimaroAbstract:The culture medium ofOryctes monoceros larva has nutrient composition and significant quantities of mineral elements required for fungi growth. The presence of these major mineral elements such as Na, Ca, K, Mg, Mn, Fe and Cu in the larva served as growth factor. The present study was carried out to examine the effect of culture media of O. monoceros larva and potato dextrose agar (PDA) in supporting growth and sporulation of fungi. TheO. monoceros larva medium best supported growth and sporulation of Ceratocystis Paradoxa(3.52),Glomerella cingulata(3.15),Trichoderma harzianum (4.80), Fusarium oxysporium (4.52) andByssochlamys nivea (3.32) while potato dextrose agar was less suitable for growth and sporulation of
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Evaluation of crude leaf extracts and benlate solution treatments on oil palm sprouted seeds for the control of Ceratocystis Paradoxa causing black seed rot
Journal of Medicinal Plants Research, 2010Co-Authors: Emmanuel I. Eziashi, E E Odigie, C. E. AiredeAbstract:Oil palm sprouted seeds inoculated with Ceratocystis Paradoxa developed symptom of black seed rot. Benlate solution and crude leaf extracts ofAzadirachta indica, Ocimum gratissimum, Acalypha wilkesiana and Carica papayawere evaluated for the control of Ceratocystis Paradoxa. Oil palm sprouted seeds treated with O. gratissimum leaves extract significantly reduced C. Paradoxainfection more than that of A. indica, A. wilkesiana, C. papaya and benlate solution. Both benlate solution and crude leaf extracts recorded poor performances on the 1st and 3rd day. Average performance was recorded on the 7th day. However, after 14 days post inoculation, mean percentage of infection using O. gratissimum were 5.0 and 3.30%, A. indica 7.80 and 5.00%, A. wilkesiana 6.10 and 5.00%, C. papaya 15.60 and 5.60%, benlate solution 7.80 and 4.40% and control 28.30 and 12.80% for wounded and unwounded sprouted seeds. Infection was higher in the wounded when compared to the unwounded. The results indicated that O. gratissimum exhibited better control than the rest of the leaf extracts and benlate solution. Key words: Ascomycetes, omnivorous pathogen, palms, black rot.
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Evaluation of lyophilized and non lyophilized toxins from Trichoderma species for the control of Ceratocystis Paradoxa.
African Journal of Agricultural Research, 2010Co-Authors: Emmanuel I. Eziashi, N. U. Uma, A. A. Adekunle, C. E. Airede, E E OdigieAbstract:Lyophilized and non-lyophilized toxins produced from Trichoderma species were investigated against Ceratocystis Paradoxa mycelial growth at different concentrations in-vitro. Lyophilized toxin inhibition on C. Paradoxa by T. viride(28.14 and 28.14%) and T. polysporum (28.88 and 28.88%) at 70 and 100% concentrations were significant (p = 0.005) compared with T. hamatum (20.37 and 21.48 %) and T. aureoviride (20.00 and 20.37%) six days after incubation. Non-lyophilized phytotoxin inhibition on C. Paradoxa mycelia by T. viride (21.85 and 23.335%) and T. polysporum (22.22 and 22.59%) at 70 and 100% were also significant (p = 0.005) when compared with T. hamatum (16.29 and 18.14%) andT. aureoviride (17.03 and 17.77%) 6 days after incubation. The mycelial growth ofC. Paradoxa was stimulated by T. hamatum and T. aureoviride at 20 and 50% concentrations with lyophilized and non-lyophilized phytotoxins. The lyophilized phytotoxin exhibited better control of C. Paradoxa compared with non-lyophilized and the control treatments. Using gas chromatography-mass spectrometry, column fraction isolated from T. viride Rf value 0.51 was deduced to be 1, 2-benzendicaboxylic acid. It is responsible for the inhibitory action on C. paradocamycelia. This compound produced by T. viride depended on type of fungus strain and standard used. Key words: GC-MS, inhibition, mycelia, 1, 2-benzendicarboxylic acid.
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antagonism of trichoderma viride and effects of extracted water soluble compounds from trichoderma species and benlate solution on Ceratocystis Paradoxa
African Journal of Biotechnology, 2007Co-Authors: Emmanuel I. Eziashi, I B Omamor, E E OdigieAbstract:Trichoderma viride was identified as a mycoparasite against Ceratocystis Paradoxa. When grown near the pathogen, T. viride was seen entwining around the pathogen mycelium. It was stimulated to produce branches that grew directly to the pathogen mycelium. Firm attachment on the pathogen conidia resulted in the penetration and successful growth of T. viride. Some of the impregnated C. Paradoxa were found death. Benlate solution and extracted water-soluble compounds from Trichoderma species were evaluated for the control of C. Paradoxa. Trichoderma polysporum significantly reduced the growth of C. Paradoxa at high concentrations (100% and 70%) followed by T. viride, T. hamatum, T. aureoviride and benlate solution recorded average performances. At (50, 30 and 10%) low concentrations, they all recorded poor performances. Minimum inhibitory concentration by T. viride was 10%, T. polysporum 25%, T. hamatum and T. aureoviride were 30% each, and benlate solution remained 50%. T. polysporum exhibited better control of the pathogen when compared with other extracted water soluble compounds from Trichoderma species and benlate solution.
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histopathology of Ceratocystis Paradoxa causing black seed rot on oil palm elaeis quineensis sprouted seeds
Advances in food sciences, 2007Co-Authors: Emmanuel I. Eziashi, I B Omamor, E A OruadedimaroAbstract:Histopathological methods were used to establish the inter-relationship of Ceratocystis Paradoxa and oil palm sprouted seeds. The conidia of C. Paradoxa germinated after 24 hours of inoculation. Penetration and colonization of host by the pathogen was through the epidermal cells. Growth in host cell led to brown coloration, maceration and disintegration of cells. The affected region became ruptured and rotten within six days. Pathogen hyphae were seen within the collapsed cells. The implications of these results were discussed.
Marcio C. Silva-filho - One of the best experts on this subject based on the ideXlab platform.
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The Sugarcane Defense Protein SUGARWIN2 Causes Cell Death in Colletotrichum falcatum but Not in Non- Pathogenic Fungi
2016Co-Authors: Flávia P. Franco, Adelita C. Santiago, Patrı́cia Alves De Castro, Gustavo H. Goldman, Daniel S. Moura, Marcio C. Silva-filhoAbstract:Plants respond to pathogens and insect attacks by inducing and accumulating a large set of defense-related proteins. Two homologues of a barley wound-inducible protein (BARWIN) have been characterized in sugarcane, SUGARWIN1 and SUGARWIN2 (sugarcane wound-inducible proteins). Induction of SUGARWINs occurs in response to Diatraea saccharalis damage but not to pathogen infection. In addition, the protein itself does not show any effect on insect development; instead, it has antimicrobial activities toward Fusarium verticillioides, an opportunistic fungus that usually occurs after D. saccharalis borer attacks on sugarcane. In this study, we sought to evaluate the specificity of SUGARWIN2 to better understand its mechanism of action against phytopathogens and the associations between fungi and insects that affect plants. We used Colletotrichum falcatum, a fungus that causes red rot disease in sugarcane fields infested by D. saccharalis, and Ceratocystis Paradoxa, which causes pineapple disease in sugarcane. We also tested whether SUGARWIN2 is able to cause cell death in Aspergillus nidulans, a fungus that does not infect sugarcane, and in the model yeast Saccharomyces cerevisiae, which is used for bioethanol production. Recombinant SUGARWIN2 altered C. falcatum morphology by increasing vacuolization, points of fractures and a leak of intracellular material, leading to germling apoptosis. In C. Paradoxa, SUGARWIN2 showed increased vacuolization in hyphae but did not kill the fungi. Neither the non-pathogenic fungus A
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The sugarcane defense protein SUGARWIN2 causes cell death in Colletotrichum falcatum but not in non-pathogenic fungi.
PloS one, 2014Co-Authors: Flávia P. Franco, Adelita C. Santiago, Gustavo H. Goldman, Daniel S. Moura, Flávio Henrique-silva, Patrícia Alves De Castro, Marcio C. Silva-filhoAbstract:Plants respond to pathogens and insect attacks by inducing and accumulating a large set of defense-related proteins. Two homologues of a barley wound-inducible protein (BARWIN) have been characterized in sugarcane, SUGARWIN1 and SUGARWIN2 (sugarcane wound-inducible proteins). Induction of SUGARWINs occurs in response to Diatraea saccharalis damage but not to pathogen infection. In addition, the protein itself does not show any effect on insect development; instead, it has antimicrobial activities toward Fusarium verticillioides, an opportunistic fungus that usually occurs after D. saccharalis borer attacks on sugarcane. In this study, we sought to evaluate the specificity of SUGARWIN2 to better understand its mechanism of action against phytopathogens and the associations between fungi and insects that affect plants. We used Colletotrichum falcatum, a fungus that causes red rot disease in sugarcane fields infested by D. saccharalis, and Ceratocystis Paradoxa, which causes pineapple disease in sugarcane. We also tested whether SUGARWIN2 is able to cause cell death in Aspergillus nidulans, a fungus that does not infect sugarcane, and in the model yeast Saccharomyces cerevisiae, which is used for bioethanol production. Recombinant SUGARWIN2 altered C. falcatum morphology by increasing vacuolization, points of fractures and a leak of intracellular material, leading to germling apoptosis. In C. Paradoxa, SUGARWIN2 showed increased vacuolization in hyphae but did not kill the fungi. Neither the non-pathogenic fungus A. nidulans nor the yeast S. cerevisiae was affected by recombinant SUGARWIN2, suggesting that the protein is specific to sugarcane opportunistic fungal pathogens.
Welington Luiz De ,araujo - One of the best experts on this subject based on the ideXlab platform.
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Biological control of soil-borne pathogens.
2013Co-Authors: As Romão-dumaresq, Nicholas J. Talbot, Welington Luiz De ,araujo, Christopher R. ThorntonAbstract:(a) Biocontrol of pineapple disease of sugarcane caused by the soil-borne pathogen Ceratocystis Paradoxa. Germination of sugarcane setts was determined in compost infested with the pathogen C. Paradoxa and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured weekly, over a 6 week period. The control consisted of sugarcane setts planted in uninfested compost. Each point is the mean of twelve replicates and percentages were converted to arc sin−1 values for statistical analysis by t-test. Points with different letters are significantly different at 95% confidence level, considering each week separately. (b) Biocontrol of pre-emergence damping-off disease of lettuce caused by the pathogen Sclerotinia sclerotiorum, Germination of lettuce seeds was determined in peat-based microcosms infested with the pathogen S. sclerotiorum and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured 10 days after sowing. The control consisted of lettuce seeds planted in uninfested peat. Each point is the mean of three replicates (each consisting of 25 lettuce seed) and percentages were converted to arc sin−1 values for statistical analysis by Tukey test for comparison of means. Histograms with different letters are significantly different at 99% confidence level. (c) Biocontrol of bean rot caused by the pathogen Rhizoctonia solani. Germination of bean seeds was determined in compost infested with the pathogen R. solani and in mixed-species microcosms containing the pathogen and chitinase-deficient mutants. Percentage germination was measured 20 days after sowing. The control consisted of bean seeds planted in uninfested compost. Each point is the mean of six replicates and percentages were converted to arc sin−1 values for statistical analysis by Tukey test for comparison of means. Histograms with different letters are significantly different at 95% confidence level.
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RNA Interference of Endochitinases in the Sugarcane Endophyte Trichoderma virens 223 Reduces Its Fitness as a Biocontrol Agent of Pineapple Disease
PloS one, 2012Co-Authors: As Romão-dumaresq, Nicholas J. Talbot, Welington Luiz De ,araujo, Christopher R. ThorntonAbstract:The sugarcane root endophyte Trichoderma virens 223 holds enormous potential as a sustainable alternative to chemical pesticides in the control of sugarcane diseases. Its efficacy as a biocontrol agent is thought to be associated with its production of chitinase enzymes, including N-acetyl-s-D-glucosaminidases, chitobiosidases and endochitinases. We used targeted gene deletion and RNA-dependent gene silencing strategies to disrupt N-acetyl-s-D-glucosaminidase and endochitinase activities of the fungus, and to determine their roles in the biocontrol of soil-borne plant pathogens. The loss of N-acetyl-s-D-glucosaminidase activities was dispensable for biocontrol of the plurivorous damping-off pathogens Rhizoctonia solani and Sclerotinia sclerotiorum, and of the sugarcane pathogen Ceratocystis Paradoxa, the causal agent of pineapple disease. Similarly, suppression of endochitinase activities had no effect on R. solani and S. sclerotiorum disease control, but had a pronounced effect on the ability of T. virens 223 to control pineapple disease. Our work demonstrates a critical requirement for T. virens 223 endochitinase activity in the biocontrol of C. Paradoxa sugarcane disease, but not for general antagonism of other soil pathogens. This may reflect its lifestyle as a sugarcane root endophyte.
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RNA Interference of Endochitinases in the Sugarcane Endophyte Trichoderma virens 223 Reduces Its Fitness as a Biocontrol Agent of Pineapple Disease
SAN FRANCISCO, 2012Co-Authors: Romao-dumaresq, Aline S., Welington Luiz De ,araujo, Talbot, Nicholas J., Thornton, Christopher R.Abstract:The sugarcane root endophyte Trichoderma virens 223 holds enormous potential as a sustainable alternative to chemical pesticides in the control of sugarcane diseases. Its efficacy as a biocontrol agent is thought to be associated with its production of chitinase enzymes, including N-acetyl-beta-D-glucosaminidases, chitobiosidases and endochitinases. We used targeted gene deletion and RNA-dependent gene silencing strategies to disrupt N-acetyl-beta-D-glucosaminidase and endochitinase activities of the fungus, and to determine their roles in the biocontrol of soil-borne plant pathogens. The loss of N-acetyl-beta-D-glucosaminidase activities was dispensable for biocontrol of the plurivorous damping-off pathogens Rhizoctonia solani and Sclerotinia sclerotiorum, and of the sugarcane pathogen Ceratocystis Paradoxa, the causal agent of pineapple disease. Similarly, suppression of endochitinase activities had no effect on R. solani and S. sclerotiorum disease control, but had a pronounced effect on the ability of T. virens 223 to control pineapple disease. Our work demonstrates a critical requirement for T. virens 223 endochitinase activity in the biocontrol of C. Paradoxa sugarcane disease, but not for general antagonism of other soil pathogens. This may reflect its lifestyle as a sugarcane root endophyte.FAPESPFAPESP [2002/14143-3]CAPESCAPE
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RNA Interference of Endochitinases in the Sugarcane Endophyte Trichoderma virens 223 Reduces Its Fitness as a Biocontrol Agent of Pineapple Disease
PUBLIC LIBRARY SCIENCE, 2012Co-Authors: Romao-dumaresq, Aline S., Welington Luiz De ,araujo, Talbot, Nicholas J., Thornton, Christopher R.Abstract:The sugarcane root endophyte Trichoderma virens 223 holds enormous potential as a sustainable alternative to chemical pesticides in the control of sugarcane diseases. Its efficacy as a biocontrol agent is thought to be associated with its production of chitinase enzymes, including N-acetyl-beta-D-glucosaminidases, chitobiosidases and endochitinases. We used targeted gene deletion and RNA-dependent gene silencing strategies to disrupt N-acetyl-beta-D-glucosaminidase and endochitinase activities of the fungus, and to determine their roles in the biocontrol of soil-borne plant pathogens. The loss of N-acetyl-beta-D-glucosaminidase activities was dispensable for biocontrol of the plurivorous damping-off pathogens Rhizoctonia solani and Sclerotinia sclerotiorum, and of the sugarcane pathogen Ceratocystis Paradoxa, the causal agent of pineapple disease. Similarly, suppression of endochitinase activities had no effect on R. solani and S. sclerotiorum disease control, but had a pronounced effect on the ability of T. virens 223 to control pineapple disease. Our work demonstrates a critical requirement for T. virens 223 endochitinase activity in the biocontrol of C. Paradoxa sugarcane disease, but not for general antagonism of other soil pathogens. This may reflect its lifestyle as a sugarcane root endophyte
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Epicoccum nigrum P16, a Sugarcane Endophyte, Produces Antifungal Compounds and Induces Root Growth
2012Co-Authors: Léia Cecilia De Lima Fávaro, Fernanda Luiza De Souza Sebastianes, Welington Luiz De ,araujoAbstract:BackgroundSugarcane is one of the most important crops in Brazil, mainly because of its use in biofuel production. Recent studies have sought to determine the role of sugarcane endophytic microbial diversity in microorganism-plant interactions, and their biotechnological potential. Epicoccum nigrum is an important sugarcane endophytic fungus that has been associated with the biological control of phytopathogens, and the production of secondary metabolites. In spite of several studies carried out to define the better conditions to use E. nigrum in different crops, little is known about the establishment of an endophytic interaction, and its potential effects on plant physiology. Methodology/Principal FindingsWe report an approach based on inoculation followed by re-isolation, molecular monitoring, microscopic analysis, plant growth responses to fungal colonization, and antimicrobial activity tests to study the basic aspects of the E. nigrum endophytic interaction with sugarcane, and the effects of colonization on plant physiology. The results indicate that E. nigrum was capable of increasing the root system biomass and producing compounds that inhibit the in vitro growth of sugarcane pathogens Fusarium verticillioides, Colletotrichum falcatum, Ceratocystis Paradoxa, and Xanthomomas albilineans. In addition, E. nigrum preferentially colonizes the sugarcane surface and, occasionally, the endophytic environment. Conclusions/SignificanceOur work demonstrates that E. nigrum has great potential for sugarcane crop application because it is capable of increasing the root system biomass and controlling pathogens. The study of the basic aspects of the interaction of E. nigrum with sugarcane demonstrated the facultative endophytism of E. nigrum and its preference for the phylloplane environment, which should be considered in future studies of biocontrol using this species. In addition, this work contributes to the knowledge of the interaction of this ubiquitous endophyte with the host plant, and also to a better use of microbial endophytes in agriculture.