[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient el...[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient element content and metabolites of C.oleifera.C.oleifera was inoculated with the suspension of Fusarium sp.in pot experiments and ammonium-N,available phosphorus,available potassi-um,organic matter,enzymes and pH of rhizosphere soil,MDA content,activity of SOD,POD of C.oleifera leaves were analyzed.[Results]Fusarium sp.stress significantly inhibited soil enzyme activities and significantly reduced available phosphorus content,especially for phospha-tase and sucrase.Antioxidant enzyme activities in C.oleifera tissues showed that Fusarium sp.stress significantly increased MDA and SOD enzyme activities and decreased POD enzyme activity.Especially,SOD enzyme activity was elevated by 53.86%compared with the CK group.In addition,analysis of the content of major metabolites in C.oleifera leaves showed that Fusarium sp.stress significantly reduced the content of total flavonoids,quercetin,isoquercitrin and isoquercitrin in C.oleifera leaves by 7.80%,50.00%and 75.90%,respectively.[Conclusions]Our results are an important step which showed strong resistance of C.oleifera and can give a novel insight for researches on the effects in the rhizosphere soil enzyme,soil nutrient elements and metabolites of C.oleifera under the Fusarium sp.too.展开更多
Onions are a horticultural crop of great economic, dietary and medicinal importance, and are highly prized by the Ivorian population. However, production remains low, due to a number of constraints, including parasiti...Onions are a horticultural crop of great economic, dietary and medicinal importance, and are highly prized by the Ivorian population. However, production remains low, due to a number of constraints, including parasitic attacks. The most frequent is fusariosis caused by Fusarium sp., a pathogen that causes enormous damage to onion crops. Faced with these attacks, chemical control appears to be ineffective, with consequences for human health and the environment. This is why the search for effective alternative methods that respect the environment and human health is so necessary. It is in this context that this study was carried out, with the general aim of controlling fusarium wilt in onion crops, with a view to improving onion production in Ivory Coast through the use of effective microorganisms. The experimental set-up used for this purpose was a fisher block with complete randomization, comprising three replicates. A fungal spore concentration of 106 spore/mL of Fusarium sp., three doses (1%;2.5% and 5% v/v) of EM and one dose of a chemical fungicide (30 mL/16L) were tested on young onion plants. Each block consisted of nine sub-plots with nine treatments. Health parameters (incidence and severity) and agronomic parameters (growth and yield) were assessed. Microbiological analysis of the EM revealed the presence of nine morphotypes of Trichoderma sp., Aspergillus clavatus, Aspergillus flavus, Aspergillus sp., Penicillium sp., Rhizopus sp., lactic acid bacteria of the Bacillus family and the yeast Saccharomyces cerevisiae. Field experimentation showed that the 5% EM microbial solution reduced the incidence and severity of fusariosis compared with the chemical fungicide, and proved to be the best. This dose reduced yield losses by 7.14%, while improving onion growth and yield by over 5%. The results demonstrated the ability of the EM solution to effectively control the causal agent of basal rot in onion crops.展开更多
Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons （PAHs） were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a...Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons （PAHs） were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene （BaP）. The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10--200 mg/kg. The scanning electronic microscope （SEM） analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP.展开更多
A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This ...A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This strain was capable of removing 500 mg phenol/L in liquid minimal medium by 99.6% within 9 h and metabolizing phenol at concentrations up to 1100 mg/L. DNA sequencing and homologous analysis of 16S rRNA gene identified PD12 to be an Acinetobacter sp. Polyvinyl alcohol （PVA） was used as a gel matrix to immobilize Acinetobacter sp. strain PDI2 by repeated freezing and thawing. The factors affecting phenol degradation of immobilized cells were investigated, and the results showed that the immobilized cells could tolerate a high phenol level and protected the bacteria against changes in temperature and pH. Storage stability and reusability tests revealed that the phenol degradation functions of immobilized cells were stable after reuse for 50 times or storing at 4℃ for 50 d. These results indicate that immobilized Acinetobacter sp. strain PD 12 possesses a good application potential in the treatment of phenol-containing wastewater.展开更多
The vascular fusariosis is one of the main obstacles in the tomato crop production. Currently, the management of the nutrient solution is presented as a control option for fusariosis, for such reason different nutrien...The vascular fusariosis is one of the main obstacles in the tomato crop production. Currently, the management of the nutrient solution is presented as a control option for fusariosis, for such reason different nutrient solutions with nitrogen (N), phosphorus (P), potassium (K) and calcium (Ca) modifications;in four saladette tomato varieties Bony Best (BB), Manapal (M), Walter (W) and FLA were evaluated in this research, in order to analyze the damage caused by Fusarium oxysporum f.sp. lycopersici (FOL) severity. Tomato plants were inoculated with 3 FOL breeds, establishing a completely random design with a factorial arrangement with six repetitions. Disease’s severity was evaluated 30 days after the inoculation using levels of (0 - 4) of the methodology established by Marlatt and Correll (1988). Afterwards, a statistical analysis was done through the Kruskal Wallis test, in which it was observed that treatments 93 (Ca 207 mg∙L<sup>-1</sup>, R3, variety BB), 95 (207 mg∙L<sup>-1</sup> Ca, R3, variety W), 81 (0Ca, R3, BB) showed less disease severity. In the foliar analysis, the best treatments were 22 (193 mg∙L<sup>-1</sup> N, R3, M) for N, the greatest P content was treatment 94 (207 mg∙L<sup>-1</sup> Ca, R3, M) for K treatment three and 93 (207 mg∙L<sup>-1</sup> Ca, R3, variety BB) greatest Ca content.展开更多
基金Supported by Key Field Project of Education Department of Guizhou Province(QJHKYZ[2021]044)Forestry Research Project of Guizhou Province(QLKH[2021]11)+1 种基金Project of Guizhou Provincial Characteristic Key Laboratory(QJHKY[2021]002)National Natural Science Foundation of China(41761010).
文摘[Objectives]To study the effects of fungi Fusarium sp.to rhizosphere soil and physiological characteristics of Camellia oleifera Abel.[Methods]We investigated the effects of Fusarium sp.to rhizosphere soil nutrient element content and metabolites of C.oleifera.C.oleifera was inoculated with the suspension of Fusarium sp.in pot experiments and ammonium-N,available phosphorus,available potassi-um,organic matter,enzymes and pH of rhizosphere soil,MDA content,activity of SOD,POD of C.oleifera leaves were analyzed.[Results]Fusarium sp.stress significantly inhibited soil enzyme activities and significantly reduced available phosphorus content,especially for phospha-tase and sucrase.Antioxidant enzyme activities in C.oleifera tissues showed that Fusarium sp.stress significantly increased MDA and SOD enzyme activities and decreased POD enzyme activity.Especially,SOD enzyme activity was elevated by 53.86%compared with the CK group.In addition,analysis of the content of major metabolites in C.oleifera leaves showed that Fusarium sp.stress significantly reduced the content of total flavonoids,quercetin,isoquercitrin and isoquercitrin in C.oleifera leaves by 7.80%,50.00%and 75.90%,respectively.[Conclusions]Our results are an important step which showed strong resistance of C.oleifera and can give a novel insight for researches on the effects in the rhizosphere soil enzyme,soil nutrient elements and metabolites of C.oleifera under the Fusarium sp.too.
文摘Onions are a horticultural crop of great economic, dietary and medicinal importance, and are highly prized by the Ivorian population. However, production remains low, due to a number of constraints, including parasitic attacks. The most frequent is fusariosis caused by Fusarium sp., a pathogen that causes enormous damage to onion crops. Faced with these attacks, chemical control appears to be ineffective, with consequences for human health and the environment. This is why the search for effective alternative methods that respect the environment and human health is so necessary. It is in this context that this study was carried out, with the general aim of controlling fusarium wilt in onion crops, with a view to improving onion production in Ivory Coast through the use of effective microorganisms. The experimental set-up used for this purpose was a fisher block with complete randomization, comprising three replicates. A fungal spore concentration of 106 spore/mL of Fusarium sp., three doses (1%;2.5% and 5% v/v) of EM and one dose of a chemical fungicide (30 mL/16L) were tested on young onion plants. Each block consisted of nine sub-plots with nine treatments. Health parameters (incidence and severity) and agronomic parameters (growth and yield) were assessed. Microbiological analysis of the EM revealed the presence of nine morphotypes of Trichoderma sp., Aspergillus clavatus, Aspergillus flavus, Aspergillus sp., Penicillium sp., Rhizopus sp., lactic acid bacteria of the Bacillus family and the yeast Saccharomyces cerevisiae. Field experimentation showed that the 5% EM microbial solution reduced the incidence and severity of fusariosis compared with the chemical fungicide, and proved to be the best. This dose reduced yield losses by 7.14%, while improving onion growth and yield by over 5%. The results demonstrated the ability of the EM solution to effectively control the causal agent of basal rot in onion crops.
基金The National Basic Research Program (973) of China (No. 2004CB418506)the National Natural Science Foundation of China (No.20337010) the Hi-Tech Research and Development Program (863) of China (No. 2004AA649060)
文摘Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons （PAHs） were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene （BaP）. The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10--200 mg/kg. The scanning electronic microscope （SEM） analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP.
基金Project supported by the Undergraduate Research Foundation of Nankai University (2004).
文摘A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This strain was capable of removing 500 mg phenol/L in liquid minimal medium by 99.6% within 9 h and metabolizing phenol at concentrations up to 1100 mg/L. DNA sequencing and homologous analysis of 16S rRNA gene identified PD12 to be an Acinetobacter sp. Polyvinyl alcohol （PVA） was used as a gel matrix to immobilize Acinetobacter sp. strain PDI2 by repeated freezing and thawing. The factors affecting phenol degradation of immobilized cells were investigated, and the results showed that the immobilized cells could tolerate a high phenol level and protected the bacteria against changes in temperature and pH. Storage stability and reusability tests revealed that the phenol degradation functions of immobilized cells were stable after reuse for 50 times or storing at 4℃ for 50 d. These results indicate that immobilized Acinetobacter sp. strain PD 12 possesses a good application potential in the treatment of phenol-containing wastewater.
文摘The vascular fusariosis is one of the main obstacles in the tomato crop production. Currently, the management of the nutrient solution is presented as a control option for fusariosis, for such reason different nutrient solutions with nitrogen (N), phosphorus (P), potassium (K) and calcium (Ca) modifications;in four saladette tomato varieties Bony Best (BB), Manapal (M), Walter (W) and FLA were evaluated in this research, in order to analyze the damage caused by Fusarium oxysporum f.sp. lycopersici (FOL) severity. Tomato plants were inoculated with 3 FOL breeds, establishing a completely random design with a factorial arrangement with six repetitions. Disease’s severity was evaluated 30 days after the inoculation using levels of (0 - 4) of the methodology established by Marlatt and Correll (1988). Afterwards, a statistical analysis was done through the Kruskal Wallis test, in which it was observed that treatments 93 (Ca 207 mg∙L<sup>-1</sup>, R3, variety BB), 95 (207 mg∙L<sup>-1</sup> Ca, R3, variety W), 81 (0Ca, R3, BB) showed less disease severity. In the foliar analysis, the best treatments were 22 (193 mg∙L<sup>-1</sup> N, R3, M) for N, the greatest P content was treatment 94 (207 mg∙L<sup>-1</sup> Ca, R3, M) for K treatment three and 93 (207 mg∙L<sup>-1</sup> Ca, R3, variety BB) greatest Ca content.
