The Experts below are selected from a list of 678 Experts worldwide ranked by ideXlab platform
Min Zhao - One of the best experts on this subject based on the ideXlab platform.
-
induction of a white laccase from the deuteromycete Myrothecium verrucaria nf 05 and its potential in decolorization of dyes
Biocatalysis and Biotransformation, 2014Co-Authors: Dan Zhao, Jian Shuai Mu, Xi Zhang, Yan Wang, Min ZhaoAbstract:Myrothecium verrucaria NF-05 is a deuteromycete fungus capable of producing a white laccase. The optimal concentration of Cu2+ for laccase production by this strain is 0.2 mM (43.23 ± 1.16 U mL− 1). A comprehensive investigation of the induction demonstrated that NF-05 laccase production could be synergistically enhanced by various inducers, including aromatic phenols, amines and recalcitrant dyes, in the presence of 0.2 mM Cu2+. Sixteen phenols, fourteen amines and four dyes exhibited significant inductive effects on laccase production. The best inducer was 3, 3’-dimethylbenzidine, which increased laccase production to 258.1 ± 11.1 U mL− 1. These results suggest that M. verrucaria NF-05 is a promising industrial laccase producer. Based on the increased production, purified NF-05 laccase was used to decolorize dyes of various structural types in the presence of six redox mediators. Among the 26 tested dyes, the decolorization rate of six azo dyes, chromotrope 2R, orange G6, Congo red, Ponceau S, amaranth ...
-
oxidation of aromatic compounds and bioelectrocatalysis of peroxide by a novel white laccase from Myrothecium verrucaria nf 05
Catalysis Communications, 2013Co-Authors: Dan Zhao, Xi Zhang, Min ZhaoAbstract:The enzymatic and electrochemical catalytic properties of a novel white laccase from Myrothecium verrucaria NF-05 were evaluated and compared with those of commercial oxidoreductases. NF-05 laccase effectively catalyzed the oxidation of several phenols and amines, indicating its wide substrate specificity. The cyclic voltammetry curves showed direct electron transfer on carbonous electrodes due to the direct absorption of NF-05 laccase. Peroxide was bioelectrochemically reduced more efficiently on NF-05 laccase-modified electrodes than on electrodes that were modified with commercial enzymes. The results demonstrate the potential applications of this enzyme in environmental bioremediation of aromatic pollutants and preparation of electronic devices.
-
purification characterization and decolorization of bilirubin oxidase from Myrothecium verrucaria 3 2190
Fungal Biology, 2012Co-Authors: Min Zhao, Lei LuAbstract:Abstract Myrothecium verrucaria 3.2190 is a nonligninolytic fungus that produces bilirubin oxidase. Both M. verrucaria and the extracellular bilirubin oxidase were tested for their ability to decolorize indigo carmine. The biosorption and biodegradation of the dye were detected during the process of decolorization; more than 98% decolorization efficiency was achieved after 7 days at 26 °C. Additionally, the crude bilirubin oxidase can efficiently decolorize indigo carmine at 30 °C∼50 °C, pH 5.5∼9.5 with dye concentrations of 50 mg l −1 ∼200 mg l −1 . Bilirubin oxidase was purified and visualized as a single band on native polyacrylamide gel electrophoresis (PAGE). Several enzymatic properties of the purified enzyme were investigated. Moreover, the identity of the purified bilirubin oxidase (BOD) was confirmed by matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS). These results demonstrate that the purified bilirubin oxidase in M. verrucaria strain has potential application in dye effluent decolorization.
-
purification characterization and decolorization of bilirubin oxidase from Myrothecium verrucaria 3 2190
Fungal Biology, 2012Co-Authors: Min Zhao, Lei LuAbstract:Abstract Myrothecium verrucaria 3.2190 is a nonligninolytic fungus that produces bilirubin oxidase. Both M. verrucaria and the extracellular bilirubin oxidase were tested for their ability to decolorize indigo carmine. The biosorption and biodegradation of the dye were detected during the process of decolorization; more than 98% decolorization efficiency was achieved after 7 days at 26 °C. Additionally, the crude bilirubin oxidase can efficiently decolorize indigo carmine at 30 °C∼50 °C, pH 5.5∼9.5 with dye concentrations of 50 mg l −1 ∼200 mg l −1 . Bilirubin oxidase was purified and visualized as a single band on native polyacrylamide gel electrophoresis (PAGE). Several enzymatic properties of the purified enzyme were investigated. Moreover, the identity of the purified bilirubin oxidase (BOD) was confirmed by matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS). These results demonstrate that the purified bilirubin oxidase in M. verrucaria strain has potential application in dye effluent decolorization.
-
characterisation of a novel white laccase from the deuteromycete fungus Myrothecium verrucaria nf 05 and its decolourisation of dyes
PLOS ONE, 2012Co-Authors: Dan Zhao, Xi Zhang, Min ZhaoAbstract:A novel ‘white’ laccase was purified from the deuteromycete fungus, Myrothecium verrucaria NF-05, which was a high laccase-producing strain (40.2 U·ml−1 on the thirteenth day during fermentation). SDS-PAGE and native-PAGE revealed a single band with laccase activity corresponding to a molecular weight of approximately 66 kDa. The enzyme had three copper and one iron atoms per protein molecule determined by ICP-AES. Furthermore, both UV/visible and EPR spectroscopy remained silence, indicating the enzyme a novel laccase with new metal compositions of active centre and spectral properties. The N-terminal amino acid sequence of the purified protein was APQISPQYPM. Together with MALDI-TOF analysis, the protein revealed a high homology of the protein with that from reported M. verrucaria. The highest activity was detected at pH 4.0 and at 30°C. The enzyme activity was significantly enhanced by Na+, Mn2+, Cu2+ and Zn2+ while inhibited by DTT, NaN3 and halogen anions. The kinetic constant (Km) showed the enzyme was more affinitive to ABTS than other tested aromatic substrates. Twelve structurally different dyes could be effectively decolourised by the laccase within 10 min. The high production of the strain and novel properties of the laccase suggested its potential for biotechnological applications.
Rosane Marina Peralta - One of the best experts on this subject based on the ideXlab platform.
-
purification and characterization of an efficient poultry feather degrading protease from Myrothecium verrucaria
Biodegradation, 2009Co-Authors: Fabiana G Moreiragasparin, Ana Maria Alexandrino, Cristina Giatti Marques De Souza, Andrea Miura Da Costa, Cissa Kelmer Bracht, Cinthia Gandolfi Boer, Rosane Marina PeraltaAbstract:The purpose of this work was to characterize an alkaline protease from the filamentous fungus Myrothecium verrucaria and to explore its capability to degrade native poultry feathers. The enzyme was purified to homogeneity using a single chromatographic step. Recovery was high, 62%, with a specific activity of 12,851.8 U/mg protein. The enzyme is a small monomeric protein with a molecular mass of 22 ± 1.5 kDa. It presented pH optimum of 8.3 and was stable over a broad pH range (5.0–12.0). The temperature optimum was 37°C, with thermal stability at temperatures up to 45°C. The enzyme presented an efficiency of 80.3% in the degradation of poultry feather meal, releasing amino acids and soluble peptides. It was able to hydrolyze β-keratin without necessity of chemical or enzymatic reduction of the disulphide bonds. Considering that, everyday, poultry-processing plants produce feathers as a waste products, this protease can be useful in biotechnological processes aiming to improve the transformation of poultry feathers through solubilization of β-keratin into usable peptides. Furthermore, it can also be useful in processes aiming to reduce the environmental pollution caused by the accumulation of feathers.
-
influence of the carbon and nitrogen sources on keratinase production by Myrothecium verrucaria in submerged and solid state cultures
Journal of Industrial Microbiology & Biotechnology, 2009Co-Authors: Nereida Mello Rosa Da Gioppo, Fabiana G Moreiragasparin, Andrea M Costa, Ana Maria Alexandrino, Cristina Giatti Marques De Souza, Rosane Marina PeraltaAbstract:Myrothecium verrucaria is a nondermatophytic filamentous fungus able to grow and to produce keratinase in submerged (93.0 ± 19 U/ml) and solid state (98.8 ± 7.9 U/ml) cultures in which poultry feather powder (PFP) is the only substrate. The purpose of the present work was to verify how different carbon and nitrogen sources can influence the production of keratinase by this fungus. Addition of carbohydrates, such as glucose and sucrose, caused only slight improvements in keratinase production, but the addition of starch caused a significant improvement (135.0 ± 25 U/ml). The highest levels of keratinase activity, however, were obtained by supplementing the PFP cultures with cassava bagasse, 168.0 ± 28 U/ml and 189.0 ± 26 U/ml in submerged and solid state cultures, respectively. Contrarily, the supplementation of PFP medium with organic or inorganic nitrogen sources, such as casein, soy bean protein, gelatin, ammonium nitrate and alanine, decreased the production of keratinase in both types of cultures (around 20 U/ml), showing that the production of keratinase by M. verrucaria is repressed by nitrogen sources. The results obtained in this work suggest that the association of the two residues PFP plus cassava bagasse could be an excellent option as a cheap culture medium for the production of keratinase in submerged and solid state cultures.
-
degradation of keratinous materials by the plant pathogenic fungus Myrothecium verrucaria
Mycopathologia, 2007Co-Authors: Fabiana Guillen Moreira, C G M De Souza, Maria Aparecida Ferreira Costa, S Reis, Rosane Marina PeraltaAbstract:In this paper it is described for the first time the capability of Myrothecium verrucaria to grow in submerged and solid state cultures using poultry feathers as the only substrate. The fungus produced a protease with an unusual keratinolytic activity among plant pathogenic fungi. Its crude protease hydrolyzed keratinous substrates at pH 9.0 and 40 °C in the following order: poultry feather keratin > sheep wool keratin > human nail keratin > human hair keratin. Protease activity was highly sensitive to phenylmethyl sulphonyl fluoride (PMSF) indicating that the enzyme belonged to the serine protease family.
-
production of hydrolytic enzymes by the plant pathogenic fungus Myrothecium verrucaria in submerged cultures
Brazilian Journal of Microbiology, 2005Co-Authors: Fabiana Guillen Moreira, Maria Aparecida Ferreira Costa, Simone Dos Reis, Cristina Giatti Marques De Souza, Rosane Marina PeraltaAbstract:The capability of the plant pathogenic fungus Myrothecium verrucaria to produce extracellular hydrolytic enzymes in submerged cultures was studied using several substrates. The fungus was able to produce different depolymerases and glycosidases, being xylanase, pectinase and protease the most important. Lipase was found in cultures developed in the presence of olive oil, while protease activity was detected in all cultures. Xylanase and pectinase were optimally active at pH 4.5-5.5, while protease was active in a large range of pH 3.5 to 11.0. All three enzymes were maximally active at 40oC and they were stable for several hours at temperature up to 50oC.
-
Production of hydrolytic enzymes by the plant pathogenic fungus Myrothecium verrucaria in submerged cultures Produção de enzimas hidrolíticas pelo fungo fitopatogênico Myrothecium verrucaria em culturas submersas
Sociedade Brasileira de Microbiologia, 2005Co-Authors: Fabiana Guillen Moreira, Maria Aparecida Ferreira Costa, Simone Dos Reis, Cristina Giatti Marques De Souza, Rosane Marina PeraltaAbstract:The capability of the plant pathogenic fungus Myrothecium verrucaria to produce extracellular hydrolytic enzymes in submerged cultures was studied using several substrates. The fungus was able to produce different depolymerases and glycosidases, being xylanase, pectinase and protease the most important. Lipase was found in cultures developed in the presence of olive oil, while protease activity was detected in all cultures. Xylanase and pectinase were optimally active at pH 4.5-5.5, while protease was active in a large range of pH 3.5 to 11.0. All three enzymes were maximally active at 40ºC and they were stable for several hours at temperature up to 50ºC.A capacidade do fungo fitopatogênico Myrothecium verrucaria produzir enzimas hidrolíticas extracelulares em culturas submersas foi estudada utilizando diversos substratos. O fungo foi capaz de produzir diferentes depolimerases e glicosidases, sendo xilanases, pectinases e proteases as mais importantes. Atividade lipase foi encontrada nos filtrados das culturas desenvolvidas na presença de óleo de oliva, enquanto atividade proteolítica foi detectada em todas as culturas. Xilanase e pectinase foram otimamente ativas em pH 4,5 a 5,5, enquanto protease foi ativa em ampla faixa de pH (3,5 a 11,0). As três enzimas foram otimamente ativas 40ºC e estáveis por várias horas a temperaturas até 50ºC
Dan Zhao - One of the best experts on this subject based on the ideXlab platform.
-
induction of a white laccase from the deuteromycete Myrothecium verrucaria nf 05 and its potential in decolorization of dyes
Biocatalysis and Biotransformation, 2014Co-Authors: Dan Zhao, Jian Shuai Mu, Xi Zhang, Yan Wang, Min ZhaoAbstract:Myrothecium verrucaria NF-05 is a deuteromycete fungus capable of producing a white laccase. The optimal concentration of Cu2+ for laccase production by this strain is 0.2 mM (43.23 ± 1.16 U mL− 1). A comprehensive investigation of the induction demonstrated that NF-05 laccase production could be synergistically enhanced by various inducers, including aromatic phenols, amines and recalcitrant dyes, in the presence of 0.2 mM Cu2+. Sixteen phenols, fourteen amines and four dyes exhibited significant inductive effects on laccase production. The best inducer was 3, 3’-dimethylbenzidine, which increased laccase production to 258.1 ± 11.1 U mL− 1. These results suggest that M. verrucaria NF-05 is a promising industrial laccase producer. Based on the increased production, purified NF-05 laccase was used to decolorize dyes of various structural types in the presence of six redox mediators. Among the 26 tested dyes, the decolorization rate of six azo dyes, chromotrope 2R, orange G6, Congo red, Ponceau S, amaranth ...
-
oxidation of aromatic compounds and bioelectrocatalysis of peroxide by a novel white laccase from Myrothecium verrucaria nf 05
Catalysis Communications, 2013Co-Authors: Dan Zhao, Xi Zhang, Min ZhaoAbstract:The enzymatic and electrochemical catalytic properties of a novel white laccase from Myrothecium verrucaria NF-05 were evaluated and compared with those of commercial oxidoreductases. NF-05 laccase effectively catalyzed the oxidation of several phenols and amines, indicating its wide substrate specificity. The cyclic voltammetry curves showed direct electron transfer on carbonous electrodes due to the direct absorption of NF-05 laccase. Peroxide was bioelectrochemically reduced more efficiently on NF-05 laccase-modified electrodes than on electrodes that were modified with commercial enzymes. The results demonstrate the potential applications of this enzyme in environmental bioremediation of aromatic pollutants and preparation of electronic devices.
-
characterisation of a novel white laccase from the deuteromycete fungus Myrothecium verrucaria nf 05 and its decolourisation of dyes
PLOS ONE, 2012Co-Authors: Dan Zhao, Xi Zhang, Min ZhaoAbstract:A novel ‘white’ laccase was purified from the deuteromycete fungus, Myrothecium verrucaria NF-05, which was a high laccase-producing strain (40.2 U·ml−1 on the thirteenth day during fermentation). SDS-PAGE and native-PAGE revealed a single band with laccase activity corresponding to a molecular weight of approximately 66 kDa. The enzyme had three copper and one iron atoms per protein molecule determined by ICP-AES. Furthermore, both UV/visible and EPR spectroscopy remained silence, indicating the enzyme a novel laccase with new metal compositions of active centre and spectral properties. The N-terminal amino acid sequence of the purified protein was APQISPQYPM. Together with MALDI-TOF analysis, the protein revealed a high homology of the protein with that from reported M. verrucaria. The highest activity was detected at pH 4.0 and at 30°C. The enzyme activity was significantly enhanced by Na+, Mn2+, Cu2+ and Zn2+ while inhibited by DTT, NaN3 and halogen anions. The kinetic constant (Km) showed the enzyme was more affinitive to ABTS than other tested aromatic substrates. Twelve structurally different dyes could be effectively decolourised by the laccase within 10 min. The high production of the strain and novel properties of the laccase suggested its potential for biotechnological applications.
Cristina Giatti Marques De Souza - One of the best experts on this subject based on the ideXlab platform.
-
purification and characterization of an efficient poultry feather degrading protease from Myrothecium verrucaria
Biodegradation, 2009Co-Authors: Fabiana G Moreiragasparin, Ana Maria Alexandrino, Cristina Giatti Marques De Souza, Andrea Miura Da Costa, Cissa Kelmer Bracht, Cinthia Gandolfi Boer, Rosane Marina PeraltaAbstract:The purpose of this work was to characterize an alkaline protease from the filamentous fungus Myrothecium verrucaria and to explore its capability to degrade native poultry feathers. The enzyme was purified to homogeneity using a single chromatographic step. Recovery was high, 62%, with a specific activity of 12,851.8 U/mg protein. The enzyme is a small monomeric protein with a molecular mass of 22 ± 1.5 kDa. It presented pH optimum of 8.3 and was stable over a broad pH range (5.0–12.0). The temperature optimum was 37°C, with thermal stability at temperatures up to 45°C. The enzyme presented an efficiency of 80.3% in the degradation of poultry feather meal, releasing amino acids and soluble peptides. It was able to hydrolyze β-keratin without necessity of chemical or enzymatic reduction of the disulphide bonds. Considering that, everyday, poultry-processing plants produce feathers as a waste products, this protease can be useful in biotechnological processes aiming to improve the transformation of poultry feathers through solubilization of β-keratin into usable peptides. Furthermore, it can also be useful in processes aiming to reduce the environmental pollution caused by the accumulation of feathers.
-
influence of the carbon and nitrogen sources on keratinase production by Myrothecium verrucaria in submerged and solid state cultures
Journal of Industrial Microbiology & Biotechnology, 2009Co-Authors: Nereida Mello Rosa Da Gioppo, Fabiana G Moreiragasparin, Andrea M Costa, Ana Maria Alexandrino, Cristina Giatti Marques De Souza, Rosane Marina PeraltaAbstract:Myrothecium verrucaria is a nondermatophytic filamentous fungus able to grow and to produce keratinase in submerged (93.0 ± 19 U/ml) and solid state (98.8 ± 7.9 U/ml) cultures in which poultry feather powder (PFP) is the only substrate. The purpose of the present work was to verify how different carbon and nitrogen sources can influence the production of keratinase by this fungus. Addition of carbohydrates, such as glucose and sucrose, caused only slight improvements in keratinase production, but the addition of starch caused a significant improvement (135.0 ± 25 U/ml). The highest levels of keratinase activity, however, were obtained by supplementing the PFP cultures with cassava bagasse, 168.0 ± 28 U/ml and 189.0 ± 26 U/ml in submerged and solid state cultures, respectively. Contrarily, the supplementation of PFP medium with organic or inorganic nitrogen sources, such as casein, soy bean protein, gelatin, ammonium nitrate and alanine, decreased the production of keratinase in both types of cultures (around 20 U/ml), showing that the production of keratinase by M. verrucaria is repressed by nitrogen sources. The results obtained in this work suggest that the association of the two residues PFP plus cassava bagasse could be an excellent option as a cheap culture medium for the production of keratinase in submerged and solid state cultures.
-
production of hydrolytic enzymes by the plant pathogenic fungus Myrothecium verrucaria in submerged cultures
Brazilian Journal of Microbiology, 2005Co-Authors: Fabiana Guillen Moreira, Maria Aparecida Ferreira Costa, Simone Dos Reis, Cristina Giatti Marques De Souza, Rosane Marina PeraltaAbstract:The capability of the plant pathogenic fungus Myrothecium verrucaria to produce extracellular hydrolytic enzymes in submerged cultures was studied using several substrates. The fungus was able to produce different depolymerases and glycosidases, being xylanase, pectinase and protease the most important. Lipase was found in cultures developed in the presence of olive oil, while protease activity was detected in all cultures. Xylanase and pectinase were optimally active at pH 4.5-5.5, while protease was active in a large range of pH 3.5 to 11.0. All three enzymes were maximally active at 40oC and they were stable for several hours at temperature up to 50oC.
-
Produção de enzimas hidrolíticas pelo fungo fitopatogênico Myrothecium verrucaria em culturas submersas
Sociedade Brasileira de Microbiologia, 2005Co-Authors: Moreira, Fabiana Guillen, Cristina Giatti Marques De Souza, Reis, Simone Dos, Costa, Maria Aparecida Ferreira, Peralta, Rosane MarinaAbstract:The capability of the plant pathogenic fungus Myrothecium verrucaria to produce extracellular hydrolytic enzymes in submerged cultures was studied using several substrates. The fungus was able to produce different depolymerases and glycosidases, being xylanase, pectinase and protease the most important. Lipase was found in cultures developed in the presence of olive oil, while protease activity was detected in all cultures. Xylanase and pectinase were optimally active at pH 4.5-5.5, while protease was active in a large range of pH 3.5 to 11.0. All three enzymes were maximally active at 40ºC and they were stable for several hours at temperature up to 50ºC.A capacidade do fungo fitopatogênico Myrothecium verrucaria produzir enzimas hidrolíticas extracelulares em culturas submersas foi estudada utilizando diversos substratos. O fungo foi capaz de produzir diferentes depolimerases e glicosidases, sendo xilanases, pectinases e proteases as mais importantes. Atividade lipase foi encontrada nos filtrados das culturas desenvolvidas na presença de óleo de oliva, enquanto atividade proteolítica foi detectada em todas as culturas. Xilanase e pectinase foram otimamente ativas em pH 4,5 a 5,5, enquanto protease foi ativa em ampla faixa de pH (3,5 a 11,0). As três enzimas foram otimamente ativas 40ºC e estáveis por várias horas a temperaturas até 50ºC
-
Production of hydrolytic enzymes by the plant pathogenic fungus Myrothecium verrucaria in submerged cultures Produção de enzimas hidrolíticas pelo fungo fitopatogênico Myrothecium verrucaria em culturas submersas
Sociedade Brasileira de Microbiologia, 2005Co-Authors: Fabiana Guillen Moreira, Maria Aparecida Ferreira Costa, Simone Dos Reis, Cristina Giatti Marques De Souza, Rosane Marina PeraltaAbstract:The capability of the plant pathogenic fungus Myrothecium verrucaria to produce extracellular hydrolytic enzymes in submerged cultures was studied using several substrates. The fungus was able to produce different depolymerases and glycosidases, being xylanase, pectinase and protease the most important. Lipase was found in cultures developed in the presence of olive oil, while protease activity was detected in all cultures. Xylanase and pectinase were optimally active at pH 4.5-5.5, while protease was active in a large range of pH 3.5 to 11.0. All three enzymes were maximally active at 40ºC and they were stable for several hours at temperature up to 50ºC.A capacidade do fungo fitopatogênico Myrothecium verrucaria produzir enzimas hidrolíticas extracelulares em culturas submersas foi estudada utilizando diversos substratos. O fungo foi capaz de produzir diferentes depolimerases e glicosidases, sendo xilanases, pectinases e proteases as mais importantes. Atividade lipase foi encontrada nos filtrados das culturas desenvolvidas na presença de óleo de oliva, enquanto atividade proteolítica foi detectada em todas as culturas. Xilanase e pectinase foram otimamente ativas em pH 4,5 a 5,5, enquanto protease foi ativa em ampla faixa de pH (3,5 a 11,0). As três enzimas foram otimamente ativas 40ºC e estáveis por várias horas a temperaturas até 50ºC
Clyde D Boyette - One of the best experts on this subject based on the ideXlab platform.
-
effects of Myrothecium verrucaria on two glyphosate resistant amaranthus palmeri biotypes differing in betacyanin content
American Journal of Plant Sciences, 2020Co-Authors: Robert E Hoagland, Clyde D Boyette, Robin H Jordan, Kenneth C. StetinaAbstract:Previously we found two biotypes of Amaranthus palmeri (Palmer amaranth) in a population of this economically important weed that were resistant to glyphosate but differed with respect to pigmentation. One biotype was typically red-pigmented (betacyanin) while the other was green, with no visual appearance of red hue on any plant part at any growth stage. We have also reported that a strain of Myrothecium verrucaria (MV) exhibited bioherbicidal activity against several important weeds including glyphosate-resistant Palmer amaranth. In greenhouse tests, MV was applied to these two biotypes (red and green) at two ages (3-week- and 6-week-old) and effects of this fungus monitored over a 5-day time course. Initial symptoms of MV (16 to 24 h after inoculation) were: epinastic curvature, wilting and development of lesions on leaves and stems. Generally, the younger plants tended to be more sensitive to MV than older plants. Bioherbicidal damage increased with time leading to necrosis and plant mortality and increasing disease progress. Severe loss of fresh weight occurred in both biotypes as compared to untreated plants. Results indicated that MV was effective on both biotypes, but effects on growth reduction and disease progression were more rapid and generally greater in the green biotype, suggesting that compounds responsible for red pigmentation may be more potent as defense against pathogen attack.
-
bioherbicidal efficacy of a Myrothecium verrucaria sector on several plant species
American Journal of Plant Sciences, 2016Co-Authors: Robert E Hoagland, Kenneth C. Stetina, Clyde D Boyette, Robin H JordanAbstract:Comparative studies were conducted on mycelial preparations of the bioherbicide, Myrothecium verrucaria (MV) strain IMI 361690 and a recently discovered sector (MV-Sector BSH) of this fungus. The whitish sector was discovered, isolated, grown in pure culture on PDA and found to be a stable, non-spore producing mutant when cultured over several months under conditions that cause circadian sporulation during growth of its MV parent. Application of MV and MV-Sector BSH mycelial preparations to intact plants (hemp sesbania and sicklepod) and leaf discs (kudzu and glyphosate-resistant Palmer amaranth) showed that the sector efficacy was generally equal to, or slightly lower than MV. Bioassays of MV and this sector on seed germination and early growth of sicklepod and hemp sesbania seeds demonstrated that hemp sesbania seeds were slightly more sensitive to the fungus than sicklepod seeds and that the sector bioherbicidal activity was slightly less than that of MV. SDS-PAGE protein profiles of cellular extracts of MV and the sector and their respective culture supernatants showed several differences with respect to quantity and number of certain protein bands. Overall results showed that the isolate was a non-spore producing mutant with phytotoxicity to several weeds (including weeds tolerant or resistant to glyphosate), and that the phytotoxic effects were generally equivalent to those caused by MV treatment. Results of this first report of a non-sporulating MV mutant that suggest additional studies on protein analysis, and an extended weed host range under greenhouse and field conditions are needed in order to further evaluate its possible bioherbicidal potential.
-
biological control of the weed hemp sesbania sesbania exaltata in rice oryza sativa by the fungus Myrothecium verrucaria
Agronomy, 2014Co-Authors: Clyde D Boyette, Robert E Hoagland, Kenneth C. StetinaAbstract:In greenhouse and field experiments, a mycelial formulation of the fungus Myrothecium verrucaria (IMI 361690) containing 0.20% Silwet L-77 surfactant exhibited high bioherbicidal efficacy against the problematic weed hemp sesbania. Infection and mortality levels of 100% of hemp sesbania seedlings occurred within 48 h after fungal application in the greenhouse. In rice field tests conducted over a three year period, M. verrucaria at an inoculum concentration of 50 g L−1 (dry mycelium equivalent) controlled 95% of ≤20 cm tall hemp sesbania plants. M. verrucaria also controlled larger plants (≥60 cm tall) using this high inoculum concentration. This level of weed control, as well as rice yields from plots where weeds were effectively controlled, were similar to those which occurred with the herbicide acifluorfen. These results suggest that a mycelial formulation of M. verrucaria has potential as a bioherbicide for controlling hemp sesbania in rice.
-
effects of Myrothecium verrucaria on morning glory ipomoea species
2011Co-Authors: Robert E Hoagland, T S Mccallister, Clyde D Boyette, Mark A Weaver, R V BeechamAbstract:During field testing of a bioherbicidal strain of the fungus Myrothecium verrucaria (MV) for control of spurges and purslanes in tomato test plots in summer of 2005, we noted extensive damage to volunteer morning-glory ( Ipomoea spp.) seedlings. This observation prompted investigations on the biological control efficacy of MV on various Ipomoea species under a controlled environment. Seven morningglory species [ivyleaf ( Ipomoea hederacea ), moonvine ( Ipomoea turbinate ), palmleaf (Ipomoea wrightii ), pitted ( Ipomoea lacunosa ), multi-color ( Ipomoea tricolor ), moonflower ( Ipomoea alba ), and cypressvine ( Ipomoea quamoclit )] were grown in greenhouse and tested at first to second leaf growth stage. MV spores (10 7 spores mL 1 ) were formulated in Silwet L-77 surfactant (0.2 %, v/v) or an invert emulsion containing this surfactant. Plants were treated either with Silwet (0.2%, v/v) alone (control), invert emulsion plus Silwet, MV plus Silwet, or MV plus Silwet plus invert emulsion via spray application. After application, the plants were placed in a dew chamber (15-18 h) and then transferred to a greenhouse. Plant injury and disease progression were assessed visually and fresh and dry weights were determined at the end of tests (7 days after treatment). Some of these species exhibited more tolerance than others to spray applications of MV plus Silwet, depending on the time after treatment. Compared to MV alone treatments, formulations of MV plus the invert emulsion promoted injury symptomology in pitted and moonvine morning-glories, but caused less disease symptomology than MV alone in palmleaf seedlings. There were no significant differences in disease symptomology of the MV alone and MV plus invert treatments in the other species. Overall, the results indicate some differential injury effects of MV on closely related species, i.e., Ipomoea (morning-glories), and that the invert emulsion can increase the efficacy of MV in certain instances.
-
improved bioherbicidal efficacy by Myrothecium verrucaria via spray adjuvants or herbicide mixtures
Biological Control, 2009Co-Authors: Mark A Weaver, Robert E Hoagland, Clyde D BoyetteAbstract:Abstract Herbicides and spray adjuvants were evaluated for compatibility with the bioherbicidal fungus, Myrothecium verrucaria. Several commercial formulations of glyphosate were found to be compatible for tank mixing with M. verrucaria, including Touchdown® and RoundUp HiTech®. Others, such as Accord XRT II® and RoundUp WeatherMAX® killed all the spores of M. verrucaria immediately after mixing at only 10% the maximum labeled application rate. Many herbicides, which were not suitable for co-application with M. verrucaria, did not inhibit the growth of the fungus when added directly to media at up to 1% concentration, indicating that these products could be compatible with M. verrucaria as sequential applications in an integrated weed management system. Several commercially available spray adjuvants and polyoxyethylene tridecyl ether (TDA) formulations were tested in vitro for their efficiency in dispersing spores and in a plant bioassay for bioherbicidal activity. All of the products improved the activity of M. verrucaria over the water-only treatments and TDA formulations with a hydrophilic–lipophilic balance (HLB) number of 8 or 10 had the highest activity. The mechanism for improved bioherbicidal activity with these adjuvants was investigated in vitro, and TDA HLB 8 and 10 did not significantly improve conidia dispersal or accelerate spore germination relative to other surfactants. It is possible that the role of the surfactant is in the alteration of the plant cuticle or otherwise preparing the infection court. Better adjuvant selection and integration with affordable synthetic herbicides should aid in the development of more cost-effective biological control of weeds.
