Aiming at searching for plant growth promoting rhizobacteria (PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identiifed as Burkholderia...Aiming at searching for plant growth promoting rhizobacteria (PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identiifed as Burkholderia sp. based on 16S rDNA sequence analysis, as wel as phenotypic and biochemical characterizations. This bacterium presented nitrogenase activity, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity and phosphate solubilizing ability;inhibited the growth of Sclerotinia sclerotiorum, Gibberel a zeae and Verticil ium dahliae;and produced smal quantities of indole acetic acid (IAA). In green house experiments, signiifcant increases in shoot height and weight, root length and weight, and stem diameter were observed on tomato plants in 30 d after inoculation with strain 7016. Result of 16S rDNA PCR-DGGE showed that 7016 survived in the rhizosphere of tomato seedlings. In the ifeld experiments, Burkholderia sp. 7016 enhanced the tomato yield and signiifcantly promoted activities of soil urease, phosphatase, sucrase, and catalase. Al these results demonstrated Burkholderia sp. 7016 as a valuable PGPR and a candidate of biofertilizer.展开更多
This study is aimed at assessing the ability of two endophytic bacteria originally isolated from healthy oil palm roots, Pseudomonas sp. （UPMP3） and Burkholderia sp. （UPMB3） to induce resistance in susceptible Ber...This study is aimed at assessing the ability of two endophytic bacteria originally isolated from healthy oil palm roots, Pseudomonas sp. （UPMP3） and Burkholderia sp. （UPMB3） to induce resistance in susceptible Berangan banana against Fusarium oxysporum race 4 （FocR4）. Increased accumulation of resistance-related enzymes such as peroxidase （PO）, phenylalanine ammonia lyase （PAL）, lignithioglycolic acid （LTGA）, and pathogenesis-related （PR） proteins （ehitinase and β-1,3-glucanase） has been observed in plantlets treated with endophytic bacteria UPMP3 and UPMB3 singly or as mixture under glasshouse conditions. Pre-inoculation of banana plantlets with UPMP3 showed a significant reduction in Fusarium wilt incidence 72 d after challenged inoculation with FocR4. UPMB3 was less effective in suppressing Fusarium wilt compared to UPMP3, whereas, the mixture of both endophytes showed an intermediate effect. Based on these results, it is concluded that UPMP3 could be a promising biological control agent that can trigger resistance against Fusarium wilt in susceptible Berangan banana.展开更多
许多研究表明人参皂苷是人参中起主要药效活性的物质,尤其是人参稀有皂苷比人参主皂苷在抗癌、抗心脑血管病、抗糖尿病等方面具有更好的疗效。利用从17年生野山参中分离、筛选获得一株人参内生真菌Burkholderia sp. GE 17-7生物转化人...许多研究表明人参皂苷是人参中起主要药效活性的物质,尤其是人参稀有皂苷比人参主皂苷在抗癌、抗心脑血管病、抗糖尿病等方面具有更好的疗效。利用从17年生野山参中分离、筛选获得一株人参内生真菌Burkholderia sp. GE 17-7生物转化人参主皂苷。通过薄层色谱法、高效液相色谱法等方法对人参主皂苷(Rb1、Rb2、Rc、Rd、Re和Rg1)的转化产物进行分离纯化,采用波谱解析及理化常数对其进行结构鉴定。同时,对转化路径进行了分析。结果表明人参内生真菌Burkholderia sp. GE 17-7能够特异性水解原人参二醇型皂苷C-20位糖基,对其内部糖基不具有水解特性。经鉴定其转化产物为人参稀有皂苷Rg3。转化路径为人参皂苷Rb1→人参皂苷Rd→人参稀有皂苷Rg3。人参内生真菌Burkholderia sp. GE 17-7能够特异性制备人参稀有皂苷Rg3,为工业制备人参稀有皂苷提供了新的微生物资源。展开更多
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
Microorganisms capable of solubilizing and mineralizing phosphorus （P） pools in soils are considered vital in promoting P bioavallability. The study was conducted to screen and isolate inorganic P-solubilizing bacte...Microorganisms capable of solubilizing and mineralizing phosphorus （P） pools in soils are considered vital in promoting P bioavallability. The study was conducted to screen and isolate inorganic P-solubilizing bacteria （IPSB） and organic P-mineralizing bacteria （OPMB） in soils taken from subtropical flooded and temperate non-flooded soils, and to compare inorganic P-solubilizing and organic P-solubilizing abilities between IPSB and OPMB. Ten OPMB strains were isolated and identified as Bacillus cereus and Bacillus megaterium, and five IPSB strains as B. megaterium, Burkholderia caryophyUi, Pseudomonas cichorii, and Pseudomonas syringae. P-solubilizing and -mineralizing abilities of the strains were measured using the methods taking cellular P into account. The IPSB strains exhibited inorganic P-solubilizing abilities ranging between 25.4-41.7 μg P mL^-1 and organic P-mineralizing abilities between 8.2-17.8μg P mL^-1. Each of the OPMB strains also exhibited both solubilizing and mineralizing abilities varying from 4.4 to 26.5 μg P mL^-1 and from 13.8 to 62.8 μg P mL^-1, respectively. For both IPSB and OPMB strains, most of the P mineralized from the organic P source was incorporated into the bacterial cells as cellular P. A significantly negative linear correlation （P 〈 0.05） was found between culture pH and P solubilized from inorganic P by OPMB strains. The results suggested that P solubilization and mineralization could coexist in the same bacterial strain.展开更多
基金supported by the National Natural Science Foundation of China (31100364)the National Nonprofit Institute Research Grant of Chinese Academy of Agricultural Sciences (CAAS, IARRP-2014-20)
文摘Aiming at searching for plant growth promoting rhizobacteria (PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identiifed as Burkholderia sp. based on 16S rDNA sequence analysis, as wel as phenotypic and biochemical characterizations. This bacterium presented nitrogenase activity, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity and phosphate solubilizing ability;inhibited the growth of Sclerotinia sclerotiorum, Gibberel a zeae and Verticil ium dahliae;and produced smal quantities of indole acetic acid (IAA). In green house experiments, signiifcant increases in shoot height and weight, root length and weight, and stem diameter were observed on tomato plants in 30 d after inoculation with strain 7016. Result of 16S rDNA PCR-DGGE showed that 7016 survived in the rhizosphere of tomato seedlings. In the ifeld experiments, Burkholderia sp. 7016 enhanced the tomato yield and signiifcantly promoted activities of soil urease, phosphatase, sucrase, and catalase. Al these results demonstrated Burkholderia sp. 7016 as a valuable PGPR and a candidate of biofertilizer.
基金the Research University Grants(RUGS 91009),Malaysia,for financing this research
文摘This study is aimed at assessing the ability of two endophytic bacteria originally isolated from healthy oil palm roots, Pseudomonas sp. （UPMP3） and Burkholderia sp. （UPMB3） to induce resistance in susceptible Berangan banana against Fusarium oxysporum race 4 （FocR4）. Increased accumulation of resistance-related enzymes such as peroxidase （PO）, phenylalanine ammonia lyase （PAL）, lignithioglycolic acid （LTGA）, and pathogenesis-related （PR） proteins （ehitinase and β-1,3-glucanase） has been observed in plantlets treated with endophytic bacteria UPMP3 and UPMB3 singly or as mixture under glasshouse conditions. Pre-inoculation of banana plantlets with UPMP3 showed a significant reduction in Fusarium wilt incidence 72 d after challenged inoculation with FocR4. UPMB3 was less effective in suppressing Fusarium wilt compared to UPMP3, whereas, the mixture of both endophytes showed an intermediate effect. Based on these results, it is concluded that UPMP3 could be a promising biological control agent that can trigger resistance against Fusarium wilt in susceptible Berangan banana.
文摘许多研究表明人参皂苷是人参中起主要药效活性的物质,尤其是人参稀有皂苷比人参主皂苷在抗癌、抗心脑血管病、抗糖尿病等方面具有更好的疗效。利用从17年生野山参中分离、筛选获得一株人参内生真菌Burkholderia sp. GE 17-7生物转化人参主皂苷。通过薄层色谱法、高效液相色谱法等方法对人参主皂苷(Rb1、Rb2、Rc、Rd、Re和Rg1)的转化产物进行分离纯化,采用波谱解析及理化常数对其进行结构鉴定。同时,对转化路径进行了分析。结果表明人参内生真菌Burkholderia sp. GE 17-7能够特异性水解原人参二醇型皂苷C-20位糖基,对其内部糖基不具有水解特性。经鉴定其转化产物为人参稀有皂苷Rg3。转化路径为人参皂苷Rb1→人参皂苷Rd→人参稀有皂苷Rg3。人参内生真菌Burkholderia sp. GE 17-7能够特异性制备人参稀有皂苷Rg3,为工业制备人参稀有皂苷提供了新的微生物资源。
基金This work was supported by “Wuhan Shi Xue Ke Dai Tou Ren Ji Hua” of the Bureau of Science and Technology of Wuhan Municipality (Grant no. 20065006131-04)
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.
基金the Scientific Research Foundation for the Returned Overseas Chinese Scholars, the Ministry of Education of the P.R. China.
文摘Microorganisms capable of solubilizing and mineralizing phosphorus （P） pools in soils are considered vital in promoting P bioavallability. The study was conducted to screen and isolate inorganic P-solubilizing bacteria （IPSB） and organic P-mineralizing bacteria （OPMB） in soils taken from subtropical flooded and temperate non-flooded soils, and to compare inorganic P-solubilizing and organic P-solubilizing abilities between IPSB and OPMB. Ten OPMB strains were isolated and identified as Bacillus cereus and Bacillus megaterium, and five IPSB strains as B. megaterium, Burkholderia caryophyUi, Pseudomonas cichorii, and Pseudomonas syringae. P-solubilizing and -mineralizing abilities of the strains were measured using the methods taking cellular P into account. The IPSB strains exhibited inorganic P-solubilizing abilities ranging between 25.4-41.7 μg P mL^-1 and organic P-mineralizing abilities between 8.2-17.8μg P mL^-1. Each of the OPMB strains also exhibited both solubilizing and mineralizing abilities varying from 4.4 to 26.5 μg P mL^-1 and from 13.8 to 62.8 μg P mL^-1, respectively. For both IPSB and OPMB strains, most of the P mineralized from the organic P source was incorporated into the bacterial cells as cellular P. A significantly negative linear correlation （P 〈 0.05） was found between culture pH and P solubilized from inorganic P by OPMB strains. The results suggested that P solubilization and mineralization could coexist in the same bacterial strain.
