An isolate GT4028 was obtained from soil samples collected from a field in Gotsu city (Kawahira), Shimane. The use of a culture suspension and culture filtrate of this isolate significantly suppressed the spore germin...An isolate GT4028 was obtained from soil samples collected from a field in Gotsu city (Kawahira), Shimane. The use of a culture suspension and culture filtrate of this isolate significantly suppressed the spore germination in Magnaporthe oryzae. The inhibitory activity of the culture filtrate was heat-stable. The formation of rice blast lesions by M. oryzae was significantly suppressed in the presence of the culture suspension of isolate GT4028. Furthermore, mycelial growth of some plant pathogenic fungi was inhibited by the isolate in a dual culture assay. Sequence analysis of 16S rDNA region of the isolate indicated that it shared similarities with species of the genus Burkholderia. Also, isolate GT4028 could be grown even in the presence of fungicides (Blastin, Kasugamycin, and Amistar) that act against M. oryzae. These results suggest that isolate GT4028 might be a potential control agent for plant protection against diseases, such as rice blast disease.展开更多
Potato is a plant that can be influenced by early blight disease. Early blight is one of the most destructive plant diseases, especially in the members of solanaceae family. This disease can reduce yield. Experiment d...Potato is a plant that can be influenced by early blight disease. Early blight is one of the most destructive plant diseases, especially in the members of solanaceae family. This disease can reduce yield. Experiment design was a factorial randomized complete design to evaluate the isolate pathogenic Alternaria solani in National Plant Gene Bank of Iran, during 2008-2009. This experiment was conducted with three replications, and the factors include test methods and three lines 9506, 10908-05 and 10908-18 with genotypes of Agria, Casmos and Desiree (susceptible) and Delta (resistant control). Analysis of variance table was based on the area under the disease progress curve, indicating the effects of the experimental methods;genotype and their interactions are significant at the 1% level. In greenhouse evaluation, the symptoms appeared on, the first day. In this method the area under the curve progression was noted in 10 times, but in vitro method, the symptoms of this evaluation appeared on the first or second day. The Evaluation was carried out after inoculation, and was noted 6 times. The results indicate that genotypes and lines are located in four different groups. In this case, line 9506 and Cosmos were quite sensitive to the surface, and Desiree, is located in a sensitive area. Line 10908-18 and Agria, located approximately at the level of resistance, and line 10908-05 and Delta, have been resistant surface.展开更多
Spore germination and appressorium formation of Magnaporthe oryzae spores was completely suppressed by an ethyl acetate extract of the culture filtrate from the H921 isolate (H921-EAE-CF). Production of antifungal sub...Spore germination and appressorium formation of Magnaporthe oryzae spores was completely suppressed by an ethyl acetate extract of the culture filtrate from the H921 isolate (H921-EAE-CF). Production of antifungal substance(s) in the H921-EAE-CF began to increase up to 3 days after isolate H921 incubation. Furthermore, heat treatment (105°C or 121°C) of H921-EAE-CF did not alter its inhibitory effect on M. oryzae spore germination compared to non-heat-treated H921-EAE-CF. Blast lesion formation inhibition by H921-EAE-CF was dose-dependent. Internal transcribed spacer (ITS) region sequence analysis indicated that this isolate shared similarities with species of the genera Trichoderma. This study suggests that H921-EAE-CF contains some antifungal substances that could be promising candidates for control of rice blast disease.展开更多
Fungal strains isolated from the fruiting bodies of wild mushrooms were evaluated for fungicidal activity against Magnaporthe oryzae, the causal agent of the rice blast disease. Fungal isolates (n = 105) were obtained...Fungal strains isolated from the fruiting bodies of wild mushrooms were evaluated for fungicidal activity against Magnaporthe oryzae, the causal agent of the rice blast disease. Fungal isolates (n = 105) were obtained from 46 samples of wild mushrooms. Infection behaviors of M. oryzae were assessed in the presence of culture filtrates from 90 fungal isolates, of which 20 inhibited spore germination. Heat-treated culture filtrates of these isolates were classified into 3 groups according to biological activity. Blast lesion formation by M. oryzae was significantly inhibited by pretreatment with culture filtrates from 4 fungal isolates. ITS region sequence analysis indicated that these?isolates shared similarities with species of the genera Annulohypoxylon, Nigrospora, and Penicillium. Studies of symbiotic and parasitic fungi from wild mushrooms may yield potential control agents for plant diseases such as the rice blast disease.展开更多
文摘An isolate GT4028 was obtained from soil samples collected from a field in Gotsu city (Kawahira), Shimane. The use of a culture suspension and culture filtrate of this isolate significantly suppressed the spore germination in Magnaporthe oryzae. The inhibitory activity of the culture filtrate was heat-stable. The formation of rice blast lesions by M. oryzae was significantly suppressed in the presence of the culture suspension of isolate GT4028. Furthermore, mycelial growth of some plant pathogenic fungi was inhibited by the isolate in a dual culture assay. Sequence analysis of 16S rDNA region of the isolate indicated that it shared similarities with species of the genus Burkholderia. Also, isolate GT4028 could be grown even in the presence of fungicides (Blastin, Kasugamycin, and Amistar) that act against M. oryzae. These results suggest that isolate GT4028 might be a potential control agent for plant protection against diseases, such as rice blast disease.
文摘Potato is a plant that can be influenced by early blight disease. Early blight is one of the most destructive plant diseases, especially in the members of solanaceae family. This disease can reduce yield. Experiment design was a factorial randomized complete design to evaluate the isolate pathogenic Alternaria solani in National Plant Gene Bank of Iran, during 2008-2009. This experiment was conducted with three replications, and the factors include test methods and three lines 9506, 10908-05 and 10908-18 with genotypes of Agria, Casmos and Desiree (susceptible) and Delta (resistant control). Analysis of variance table was based on the area under the disease progress curve, indicating the effects of the experimental methods;genotype and their interactions are significant at the 1% level. In greenhouse evaluation, the symptoms appeared on, the first day. In this method the area under the curve progression was noted in 10 times, but in vitro method, the symptoms of this evaluation appeared on the first or second day. The Evaluation was carried out after inoculation, and was noted 6 times. The results indicate that genotypes and lines are located in four different groups. In this case, line 9506 and Cosmos were quite sensitive to the surface, and Desiree, is located in a sensitive area. Line 10908-18 and Agria, located approximately at the level of resistance, and line 10908-05 and Delta, have been resistant surface.
文摘Spore germination and appressorium formation of Magnaporthe oryzae spores was completely suppressed by an ethyl acetate extract of the culture filtrate from the H921 isolate (H921-EAE-CF). Production of antifungal substance(s) in the H921-EAE-CF began to increase up to 3 days after isolate H921 incubation. Furthermore, heat treatment (105°C or 121°C) of H921-EAE-CF did not alter its inhibitory effect on M. oryzae spore germination compared to non-heat-treated H921-EAE-CF. Blast lesion formation inhibition by H921-EAE-CF was dose-dependent. Internal transcribed spacer (ITS) region sequence analysis indicated that this isolate shared similarities with species of the genera Trichoderma. This study suggests that H921-EAE-CF contains some antifungal substances that could be promising candidates for control of rice blast disease.
文摘Fungal strains isolated from the fruiting bodies of wild mushrooms were evaluated for fungicidal activity against Magnaporthe oryzae, the causal agent of the rice blast disease. Fungal isolates (n = 105) were obtained from 46 samples of wild mushrooms. Infection behaviors of M. oryzae were assessed in the presence of culture filtrates from 90 fungal isolates, of which 20 inhibited spore germination. Heat-treated culture filtrates of these isolates were classified into 3 groups according to biological activity. Blast lesion formation by M. oryzae was significantly inhibited by pretreatment with culture filtrates from 4 fungal isolates. ITS region sequence analysis indicated that these?isolates shared similarities with species of the genera Annulohypoxylon, Nigrospora, and Penicillium. Studies of symbiotic and parasitic fungi from wild mushrooms may yield potential control agents for plant diseases such as the rice blast disease.
