[Objective] The research aimed to study the optimum liquid fermentation condition of Trichoderma hamatum Th12 strain,which provided the theory basis for studying and developing the biological control agent of Trichode...[Objective] The research aimed to study the optimum liquid fermentation condition of Trichoderma hamatum Th12 strain,which provided the theory basis for studying and developing the biological control agent of Trichoderma spp.[Method] By using the diluted soil plate method and the plate confrontation method,Trichoderma hamatum Th12 strain was identified.Moreover,the influences of carbon source,nitrogen source,fermentation time,fermentation temperature,initial pH,inoculation amount,bottling capacity and shaker speed on the mycelium yield of Trichoderma hamatum Th12 were studied.[Result] The optimum liquid fermentation conditions of Trichoderma hamatum Th12 strain were:glucose as the carbon source,peptone as the nitrogen source,fermentation temperature was 25 ℃,initial pH was 6,inoculation amount was 0.8 ml,bottling capacity was 50 ml,shaker speed was 180 r/min.Trichoderma hamatum Th12 strain was cultivated 3 d under the condition,and the mycelium yield was the highest.[Conclusion] Under the optimum liquid cultivation condition,Trichoderma hamatum Th12 strain could provide the mycelium amount which was used for preventing and controlling Fusarium oxysporum and Rhizoctonia solani of lawn to the utmost extent.展开更多
Trichoderma strains are used in agriculture because they provide to the plants the following benefits: i) are rhizosphere competence and establish stable rhizosphere microbial communities; ii) control plant disease ca...Trichoderma strains are used in agriculture because they provide to the plants the following benefits: i) are rhizosphere competence and establish stable rhizosphere microbial communities; ii) control plant disease caused by pathogenic and competitive microflora, by using a variety of mechanisms; iii) improve vegetative growth, root development and yield; iv) make nutrients more available to the plant. In this work we have investigated the ability of T. harzianum T22 and T. atroviride P1 to improve plant growth of locally important horticultural crops: lettuce, tomatoes and peppers and to prevent disease in the greenhouse and field. The effect of the Trichoderma treatment was evaluated by determining the weight of fresh and dry roots and above ground plant biomass, measuring plants height, counting the number of emerged leaves (lettuce, tomatoes and peppers) and quantifying production (tomatoes and peppers). No disease symptoms were found during production, although Fusarium sp. strains pathogenic to tomato were detected in the soil. Compounds containing copper oxychloride are frequently used for fungal disease control in agriculture. In order to investigate the compatibility of T. harzianum T22 and T. atroviride P1 with copper oxychloride applications, the effect on mycelia growth was monitored in both liquid and solid medium. In general, the tests indicated a high level of tolerance of the Trichoderma strains to concentrations of copper oxychloride varying from 0.1 to 5 mmol/L.展开更多
The choice of active Trichoderma strains is important in designing effective and safe biocontrol applications. Many species of Trichoderma have multiple strategies for fungal antagonism and indirect effects on plant h...The choice of active Trichoderma strains is important in designing effective and safe biocontrol applications. Many species of Trichoderma have multiple strategies for fungal antagonism and indirect effects on plant health, such as growth promotion, systemic resistance induction and fertility improvements. Some strains are powerful antibiotic producers, and their suitability for use in biocontrol systems must be carefully assessed. However, many other active strains have no antibiotic capacity, and these are likely to be more useful in food production systems since they have not adverse effects on important groups of beneficial soil organisms. We have assessed the performance of selected naturally occurring Trichoderma strains (singly and in combination) and developed TUSAL, a mixture of Trichoderma harzianum and T. viride that has demonstrated to be effective against major pathogens in sugar beet and horticulture. TUSAL, has been bulked up and tested under field conditions, showing positive effects on precocity and root development, and increasing the crop production in field trials carried out in different pathosystems. The environmental impact of TUSAL strains on beneficial organisms in the environment were assessed before release, and molecular detection methods were developed to monitor the presence and performance of strains in the field. In addition, Trichoderma protein extracts with high glucanase and chitinase activities, have also been obtained from wild type strains and their effectiveness as biofungicides was tested in laboratory and field conditions, defining the concentration of protein necessary to produce fungicide effects. The genes coding for protein production were introduced into suitable organisms for large-scale production in the laboratory, never released to the environment. The effect of these novel biofungicide proteins was studied separately and synergistically with Trichoderma conidia, and with minimal doses of chemical fungicides. Suitable active Trichoderma strains are being registered in the EU by the company NBT. Both Trichoderma strains and proteins are included in formulations patented as biocontrol agents.展开更多
Phytophthora species are particularly aggressive plant pathogens and are often associated with the decline of many tree species, including oak and beech. Several fungi and bacteria species are known as potential antag...Phytophthora species are particularly aggressive plant pathogens and are often associated with the decline of many tree species, including oak and beech. Several fungi and bacteria species are known as potential antagonists usable as biological control agents. Phosphonate (H3PO3), commonly branded as phosphite, has also been used in the past years to protect trees against invasive Phytophthora spp.. This study aimed at comparing the effects of selected antagonist microorganisms and phosphonate, when applied by microinjection or leaf treatment. Antagonistic species were first selected for their high inhibitory activity against problematic Phytophthora species, such as Phytophthora cactorum, P. quercina and P. plurivora attacking Quercus robur and Fagus sylvatica in Polish forests. Three endophytic species Trichoderma atroviride (two strains), T. harzianum and Bacillus amyloliquefaciens showed a high control activity, and their efficacy was then assessed in comparison with a phosphonate treatment. Two application methods were experimented in this study: injection of a solution of spores or phosphonate into the sap vessels of beech or a foliar treatment on oak. Phosphonate and two strains of Trichoderma significantly reduced the necrotic area on oak leaves inoculated with P. plurivora and one strain of T. atroviride significantly reduced necrotic areas on beech branches. These results are therefore promising of a novel way to control Phytophthora spp. in forest stands and nurseries.展开更多
文摘[Objective] The research aimed to study the optimum liquid fermentation condition of Trichoderma hamatum Th12 strain,which provided the theory basis for studying and developing the biological control agent of Trichoderma spp.[Method] By using the diluted soil plate method and the plate confrontation method,Trichoderma hamatum Th12 strain was identified.Moreover,the influences of carbon source,nitrogen source,fermentation time,fermentation temperature,initial pH,inoculation amount,bottling capacity and shaker speed on the mycelium yield of Trichoderma hamatum Th12 were studied.[Result] The optimum liquid fermentation conditions of Trichoderma hamatum Th12 strain were:glucose as the carbon source,peptone as the nitrogen source,fermentation temperature was 25 ℃,initial pH was 6,inoculation amount was 0.8 ml,bottling capacity was 50 ml,shaker speed was 180 r/min.Trichoderma hamatum Th12 strain was cultivated 3 d under the condition,and the mycelium yield was the highest.[Conclusion] Under the optimum liquid cultivation condition,Trichoderma hamatum Th12 strain could provide the mycelium amount which was used for preventing and controlling Fusarium oxysporum and Rhizoctonia solani of lawn to the utmost extent.
文摘Trichoderma strains are used in agriculture because they provide to the plants the following benefits: i) are rhizosphere competence and establish stable rhizosphere microbial communities; ii) control plant disease caused by pathogenic and competitive microflora, by using a variety of mechanisms; iii) improve vegetative growth, root development and yield; iv) make nutrients more available to the plant. In this work we have investigated the ability of T. harzianum T22 and T. atroviride P1 to improve plant growth of locally important horticultural crops: lettuce, tomatoes and peppers and to prevent disease in the greenhouse and field. The effect of the Trichoderma treatment was evaluated by determining the weight of fresh and dry roots and above ground plant biomass, measuring plants height, counting the number of emerged leaves (lettuce, tomatoes and peppers) and quantifying production (tomatoes and peppers). No disease symptoms were found during production, although Fusarium sp. strains pathogenic to tomato were detected in the soil. Compounds containing copper oxychloride are frequently used for fungal disease control in agriculture. In order to investigate the compatibility of T. harzianum T22 and T. atroviride P1 with copper oxychloride applications, the effect on mycelia growth was monitored in both liquid and solid medium. In general, the tests indicated a high level of tolerance of the Trichoderma strains to concentrations of copper oxychloride varying from 0.1 to 5 mmol/L.
文摘The choice of active Trichoderma strains is important in designing effective and safe biocontrol applications. Many species of Trichoderma have multiple strategies for fungal antagonism and indirect effects on plant health, such as growth promotion, systemic resistance induction and fertility improvements. Some strains are powerful antibiotic producers, and their suitability for use in biocontrol systems must be carefully assessed. However, many other active strains have no antibiotic capacity, and these are likely to be more useful in food production systems since they have not adverse effects on important groups of beneficial soil organisms. We have assessed the performance of selected naturally occurring Trichoderma strains (singly and in combination) and developed TUSAL, a mixture of Trichoderma harzianum and T. viride that has demonstrated to be effective against major pathogens in sugar beet and horticulture. TUSAL, has been bulked up and tested under field conditions, showing positive effects on precocity and root development, and increasing the crop production in field trials carried out in different pathosystems. The environmental impact of TUSAL strains on beneficial organisms in the environment were assessed before release, and molecular detection methods were developed to monitor the presence and performance of strains in the field. In addition, Trichoderma protein extracts with high glucanase and chitinase activities, have also been obtained from wild type strains and their effectiveness as biofungicides was tested in laboratory and field conditions, defining the concentration of protein necessary to produce fungicide effects. The genes coding for protein production were introduced into suitable organisms for large-scale production in the laboratory, never released to the environment. The effect of these novel biofungicide proteins was studied separately and synergistically with Trichoderma conidia, and with minimal doses of chemical fungicides. Suitable active Trichoderma strains are being registered in the EU by the company NBT. Both Trichoderma strains and proteins are included in formulations patented as biocontrol agents.
文摘Phytophthora species are particularly aggressive plant pathogens and are often associated with the decline of many tree species, including oak and beech. Several fungi and bacteria species are known as potential antagonists usable as biological control agents. Phosphonate (H3PO3), commonly branded as phosphite, has also been used in the past years to protect trees against invasive Phytophthora spp.. This study aimed at comparing the effects of selected antagonist microorganisms and phosphonate, when applied by microinjection or leaf treatment. Antagonistic species were first selected for their high inhibitory activity against problematic Phytophthora species, such as Phytophthora cactorum, P. quercina and P. plurivora attacking Quercus robur and Fagus sylvatica in Polish forests. Three endophytic species Trichoderma atroviride (two strains), T. harzianum and Bacillus amyloliquefaciens showed a high control activity, and their efficacy was then assessed in comparison with a phosphonate treatment. Two application methods were experimented in this study: injection of a solution of spores or phosphonate into the sap vessels of beech or a foliar treatment on oak. Phosphonate and two strains of Trichoderma significantly reduced the necrotic area on oak leaves inoculated with P. plurivora and one strain of T. atroviride significantly reduced necrotic areas on beech branches. These results are therefore promising of a novel way to control Phytophthora spp. in forest stands and nurseries.