[Objective] The aim of this study was to screen bacteria strains with stable antagonistic effect against watermelon fusarium wilt from soil and investigate the biological control of watermelon fusarium wilt by applyin...[Objective] The aim of this study was to screen bacteria strains with stable antagonistic effect against watermelon fusarium wilt from soil and investigate the biological control of watermelon fusarium wilt by applying the antagonistic bacteria strains into soil.[Method] Actinomycete strains,fluorescent bacteria strains and bacillus strains were isolated from soil samples by the dilution-plate method,then its resistance was screened respectively by the improved confront culture method after colonies were purified.Finally,bacteria strains with better antagonistic effect were identified.[Result] 29 bacteria strains with stable antagonistic effect against watermelon fusarium wilt were screened from 39 soil samples,which contained 15 fluorescent bacteria strains,5 bacillus strains and 9 actinomycete strains.Furthermore,three antagonistic bacteria strains of FM2,FM3 and FM4 with the strongest antagonism were identified primarily.[Conclusion] According to cultural characteristics,morphological observation,biochemical and physiological tests,FM2 belongs to bacillus subtilis,while FM3 and FM4 belong to micrococcus.展开更多
High-throughput sequencing technique was applied to analyze the microbial community structure of rhizosphere soil at different stages of watermelon fusarium wilt to find out the difference of dominant microbial commun...High-throughput sequencing technique was applied to analyze the microbial community structure of rhizosphere soil at different stages of watermelon fusarium wilt to find out the difference of dominant microbial community in rhizosphere during the occurrence of watermelon fusarium wilt.Illumina-Hiseq high-throughput sequencing platform was used to sequence 16S and ITS rDNA in rhizosphere soil.The soil was named CK1 before planting,CK2 at peak stage and CK3 at stable stage.The results showed that the soil bacterial diversity was in the order of CK1>CK3>CK2,indicating no significant difference between CK1 and CK3 and a significant difference between CK2 and CK1,CK3.At the genus level,the dominant bacteria were Mizugakiibacter(21.9299%),Rhodanobacter(5.0933%),and Lactobacillus(3.1921%).The diversity of soil fungi was in the order of CK1>CK3>CK2,all showing significant differences.At the genus level,the dominant fungus was Lysurus(54.4601%),Papulaspora(12.4252%),Acrophialophora(3.1729%).The results showed that the diversity and abundance of bacteria and fungi in rhizosphere soil decreased during the peak period of watermelon fusarium wilt.With the gradual stabilization of the disease,the diversity and abundance of bacteria and fungi in rhizosphere soil recovered to a certain extent.展开更多
With conventional fertilization as the control, the control effects of biological fertilizer and general organic fertilizer on watermelon Fusarium wilt were studied in the paper. The results showed that applying biolo...With conventional fertilization as the control, the control effects of biological fertilizer and general organic fertilizer on watermelon Fusarium wilt were studied in the paper. The results showed that applying biological fertilizer could effectively reduce the incidence rate of watermelon Fusarium wilt and significantly improve the quality of watermelon, while application of general organic fertilizer had no obvious control effect on watermelon Fusarium wilt.展开更多
[Objective] This study aimed to isolate and purify the antifungal protein against Fusarium oxysporum f. sp niveum （FON） from Bacillus subtilis XG-I. [Method] The crude protein was obtained by using fractional precip...[Objective] This study aimed to isolate and purify the antifungal protein against Fusarium oxysporum f. sp niveum （FON） from Bacillus subtilis XG-I. [Method] The crude protein was obtained by using fractional precipitation with am- monium sulfate, then chromatography using both DEAE-Sepharose FF anion ex- change and Sephacryl S-100 gel filtration columns was adopted for further purifica- tion of the protein, followed by MALDI-TOF-MS analysis of the structure of the at- tained protein which was antagonistic to FON. [Result] The result from MALDI-TOF- MS analysis suggested that the antifungal protein extracted from strain XG-1 was highly homologous to the flagellin （gi114278900） deriving from B. subtilis, with a pro- tein score of 248 and a coverage rate of 63%. It was thus speculated that this an- tagonistic protein was a kind of flagellin with a molecular mass of 30.6 kD. [Conclusion] The results from this study provide theoretical basis for clarifying the mechanisms of the action of strain XG-1 as well as important references for the preven- tion and control of watermelon Fusarium wilt.展开更多
[Objective] The aim of this study was to breed new strains which have higher inhibitory effects on the pathogens of watermelon fusarium wilt.[Method] The endophytic Bacillus subtilis B47 strain was obtained from tomat...[Objective] The aim of this study was to breed new strains which have higher inhibitory effects on the pathogens of watermelon fusarium wilt.[Method] The endophytic Bacillus subtilis B47 strain was obtained from tomato stems by UV mutagenesis for two consecutive times,then genetic stability as well as physiological and biochemical properties of mutant strains were studied.[Result] The antibacterial activity of all the three mutant strains F303,F304 and F305 was higher than that of B74 strain.After subculture of 10 successive generations,the antibacterial activity of all the three mutant strains for the pathogens of watermelon fusarium wilt decreased,but the antibacterial activity of F305 strain decreased the least,indicating its best genetic stability among the tested strains.The antibacterial circle diameter of F305 strain was 5 mm larger than that of wild strain B47 under the same condition.The mutant strain F305 was in logarithmic growth phase within 36 h and in stationary phase within 36-96 h,while its optimum growth temperature was 35 ℃.F305 strain could grow in sodium salt with the concentration of 1%-10%,but it grew best at the concentration of 1%.Physiological and biochemical responses of F305 strain were in accordance with those of wild strain B47.[Conclusion] This study lays the foundation for the factorial production of antagonistic substance by B47 strain and new methods of preventing from the pathogens watermelon fusarium wilt.展开更多
基金Supported by Scientific Research and Development Fund of Hefei University of Technology(070602F)Research Funding Project for Young Teachers in Colleges of Anhui Province(2008JQ1009)~~
文摘[Objective] The aim of this study was to screen bacteria strains with stable antagonistic effect against watermelon fusarium wilt from soil and investigate the biological control of watermelon fusarium wilt by applying the antagonistic bacteria strains into soil.[Method] Actinomycete strains,fluorescent bacteria strains and bacillus strains were isolated from soil samples by the dilution-plate method,then its resistance was screened respectively by the improved confront culture method after colonies were purified.Finally,bacteria strains with better antagonistic effect were identified.[Result] 29 bacteria strains with stable antagonistic effect against watermelon fusarium wilt were screened from 39 soil samples,which contained 15 fluorescent bacteria strains,5 bacillus strains and 9 actinomycete strains.Furthermore,three antagonistic bacteria strains of FM2,FM3 and FM4 with the strongest antagonism were identified primarily.[Conclusion] According to cultural characteristics,morphological observation,biochemical and physiological tests,FM2 belongs to bacillus subtilis,while FM3 and FM4 belong to micrococcus.
文摘High-throughput sequencing technique was applied to analyze the microbial community structure of rhizosphere soil at different stages of watermelon fusarium wilt to find out the difference of dominant microbial community in rhizosphere during the occurrence of watermelon fusarium wilt.Illumina-Hiseq high-throughput sequencing platform was used to sequence 16S and ITS rDNA in rhizosphere soil.The soil was named CK1 before planting,CK2 at peak stage and CK3 at stable stage.The results showed that the soil bacterial diversity was in the order of CK1>CK3>CK2,indicating no significant difference between CK1 and CK3 and a significant difference between CK2 and CK1,CK3.At the genus level,the dominant bacteria were Mizugakiibacter(21.9299%),Rhodanobacter(5.0933%),and Lactobacillus(3.1921%).The diversity of soil fungi was in the order of CK1>CK3>CK2,all showing significant differences.At the genus level,the dominant fungus was Lysurus(54.4601%),Papulaspora(12.4252%),Acrophialophora(3.1729%).The results showed that the diversity and abundance of bacteria and fungi in rhizosphere soil decreased during the peak period of watermelon fusarium wilt.With the gradual stabilization of the disease,the diversity and abundance of bacteria and fungi in rhizosphere soil recovered to a certain extent.
基金Supported by Special Fund for Nonprofit Industry of Ministry of Agriculture(2011R20A24B02)Support Project of Science and Technology Ministry(2012BAC17B02-2-1)+1 种基金Nonprofit Agricultural Research Projects of Zhejiang Province(2010C32016)Provincial Major Science and Technology Projects(priority topics)for Agricultural Program(2008C12045-1)
文摘With conventional fertilization as the control, the control effects of biological fertilizer and general organic fertilizer on watermelon Fusarium wilt were studied in the paper. The results showed that applying biological fertilizer could effectively reduce the incidence rate of watermelon Fusarium wilt and significantly improve the quality of watermelon, while application of general organic fertilizer had no obvious control effect on watermelon Fusarium wilt.
基金Supported by the Research Fund for Mid-career and Young Scientists of Education Department of Hubei Province(Q2011130)~~
文摘[Objective] This study aimed to isolate and purify the antifungal protein against Fusarium oxysporum f. sp niveum （FON） from Bacillus subtilis XG-I. [Method] The crude protein was obtained by using fractional precipitation with am- monium sulfate, then chromatography using both DEAE-Sepharose FF anion ex- change and Sephacryl S-100 gel filtration columns was adopted for further purifica- tion of the protein, followed by MALDI-TOF-MS analysis of the structure of the at- tained protein which was antagonistic to FON. [Result] The result from MALDI-TOF- MS analysis suggested that the antifungal protein extracted from strain XG-1 was highly homologous to the flagellin （gi114278900） deriving from B. subtilis, with a pro- tein score of 248 and a coverage rate of 63%. It was thus speculated that this an- tagonistic protein was a kind of flagellin with a molecular mass of 30.6 kD. [Conclusion] The results from this study provide theoretical basis for clarifying the mechanisms of the action of strain XG-1 as well as important references for the preven- tion and control of watermelon Fusarium wilt.
基金Supported by the Fund of Science and Technology in GuangXi Zhuang Autonomous Region(0009018)~~
文摘[Objective] The aim of this study was to breed new strains which have higher inhibitory effects on the pathogens of watermelon fusarium wilt.[Method] The endophytic Bacillus subtilis B47 strain was obtained from tomato stems by UV mutagenesis for two consecutive times,then genetic stability as well as physiological and biochemical properties of mutant strains were studied.[Result] The antibacterial activity of all the three mutant strains F303,F304 and F305 was higher than that of B74 strain.After subculture of 10 successive generations,the antibacterial activity of all the three mutant strains for the pathogens of watermelon fusarium wilt decreased,but the antibacterial activity of F305 strain decreased the least,indicating its best genetic stability among the tested strains.The antibacterial circle diameter of F305 strain was 5 mm larger than that of wild strain B47 under the same condition.The mutant strain F305 was in logarithmic growth phase within 36 h and in stationary phase within 36-96 h,while its optimum growth temperature was 35 ℃.F305 strain could grow in sodium salt with the concentration of 1%-10%,but it grew best at the concentration of 1%.Physiological and biochemical responses of F305 strain were in accordance with those of wild strain B47.[Conclusion] This study lays the foundation for the factorial production of antagonistic substance by B47 strain and new methods of preventing from the pathogens watermelon fusarium wilt.
