Incessant application of chemical fertilizers to the agricultural fields may alter the composition and activities of soil microbiota.Thus,the shift of cultivation practices from chemical to organic is considered to be...Incessant application of chemical fertilizers to the agricultural fields may alter the composition and activities of soil microbiota.Thus,the shift of cultivation practices from chemical to organic is considered to be the need of the hour in order to maintain soil health.A study was conducted in the agricultural fields of the University of Burdwan,India to observe the impact of organic manure on the rhizosphere bacterial community.The experiments were conducted on maize plants,supplemented with the recommended dose of chemical fertilizer and organic manure(vermicompost and cow dung mixture).Corresponding changes in the plant phenological events and soil health in terms of soil physico-chemical factors and rhizosphere bacterial groups up to the level of CFU g-1×105 dry soil was noted.The results showed a significant increase in population of phosphate solubilizing bacteria during 30DAS.However,at 90 DAS,significant increase in the population of phosphate solubilizing bacteria,nitrifying bacteria,asymbiotic nitrogen-fixing bacteria and protein hydrolyzing bacteria was observed in the organically treated plots.The growth of rhizosphere bacteria was attributed to the type of organic manure supplied to the agricultural fields.In addition,a strong correlation was observed between Zn and protein hydrolyzing bacteria.The soil organic carbon and available nitrogen were strongly correlated with nitrifying,fat solubilizing and phosphate solubilizing groups of bacteria.展开更多
Microbe communities in rhizosphere ecosystems are important for plant health but there is limited knowledge of them in the rhizospheres of genetically modified（GM） plants, especial for tree species. We used the ampl...Microbe communities in rhizosphere ecosystems are important for plant health but there is limited knowledge of them in the rhizospheres of genetically modified（GM） plants, especial for tree species. We used the amplitude sequencing method to analyze the V4 regions of the 16 S r RNA gene to identify changes in bacterial diversity and community structure in two GM lines（D520 and D521）, one non-genetically modified（nonGM） line and in uncultivated soil. After chimera filtering,468.133 sequences in the domain Bacteria remained. There were ten dominant taxonomic groups（with [1 % of all sequences） across the samples. 241 of 551 genera（representing a ratio of 97.33 %） were common to all samples.A Venn diagram showed that 1.926 operational taxonomic units（OTUs） were shared by all samples. We found a specific change, a reduction in Chloroflexi, in the microorganisms in the rhizosphere soil planted with poplars. Taken together, the results showed few statistical differences in the bacterial diversity and community structure between the GM line and non-GM line, this suggests that there was no or very limited impact of this genetic modification on the bacterial communities in the rhizosphere.展开更多
文摘Incessant application of chemical fertilizers to the agricultural fields may alter the composition and activities of soil microbiota.Thus,the shift of cultivation practices from chemical to organic is considered to be the need of the hour in order to maintain soil health.A study was conducted in the agricultural fields of the University of Burdwan,India to observe the impact of organic manure on the rhizosphere bacterial community.The experiments were conducted on maize plants,supplemented with the recommended dose of chemical fertilizer and organic manure(vermicompost and cow dung mixture).Corresponding changes in the plant phenological events and soil health in terms of soil physico-chemical factors and rhizosphere bacterial groups up to the level of CFU g-1×105 dry soil was noted.The results showed a significant increase in population of phosphate solubilizing bacteria during 30DAS.However,at 90 DAS,significant increase in the population of phosphate solubilizing bacteria,nitrifying bacteria,asymbiotic nitrogen-fixing bacteria and protein hydrolyzing bacteria was observed in the organically treated plots.The growth of rhizosphere bacteria was attributed to the type of organic manure supplied to the agricultural fields.In addition,a strong correlation was observed between Zn and protein hydrolyzing bacteria.The soil organic carbon and available nitrogen were strongly correlated with nitrifying,fat solubilizing and phosphate solubilizing groups of bacteria.
基金financially supported by the National High-Tech Research and Development Program of China,863Program(Grant No.2011AA100201)the National Forestry Public Welfare Research Project of China(Grant No.201004004)
文摘Microbe communities in rhizosphere ecosystems are important for plant health but there is limited knowledge of them in the rhizospheres of genetically modified（GM） plants, especial for tree species. We used the amplitude sequencing method to analyze the V4 regions of the 16 S r RNA gene to identify changes in bacterial diversity and community structure in two GM lines（D520 and D521）, one non-genetically modified（nonGM） line and in uncultivated soil. After chimera filtering,468.133 sequences in the domain Bacteria remained. There were ten dominant taxonomic groups（with [1 % of all sequences） across the samples. 241 of 551 genera（representing a ratio of 97.33 %） were common to all samples.A Venn diagram showed that 1.926 operational taxonomic units（OTUs） were shared by all samples. We found a specific change, a reduction in Chloroflexi, in the microorganisms in the rhizosphere soil planted with poplars. Taken together, the results showed few statistical differences in the bacterial diversity and community structure between the GM line and non-GM line, this suggests that there was no or very limited impact of this genetic modification on the bacterial communities in the rhizosphere.
