@article {374,
	title = {Effects of selected root exudate components on soil bacterial communities.},
	journal = {FEMS Microbiol Ecol},
	volume = {77},
	year = {2011},
	month = {2011 Sep},
	pages = {600-10},
	abstract = {Low-molecular-weight organic compounds in root exudates play a key role in plant-microorganism interactions by influencing the structure and function of soil microbial communities. Model exudate solutions, based on organic acids (OAs) (quinic, lactic, maleic acids) and sugars (glucose, sucrose, fructose), previously identified in the rhizosphere of Pinus radiata, were applied to soil microcosms. Root exudate compound solutions stimulated soil dehydrogenase activity and the addition of OAs increased soil pH. The structure of active bacterial communities, based on reverse-transcribed 16S rRNA gene PCR, was assessed by denaturing gradient gel electrophoresis and PhyloChip microarrays. Bacterial taxon richness was greater in all treatments than that in control soil, with a wide range of taxa (88-1043) responding positively to exudate solutions and fewer (<24) responding negatively. OAs caused significantly greater increases than sugars in the detectable richness of the soil bacterial community and larger shifts of dominant taxa. The greater response of bacteria to OAs may be due to the higher amounts of added carbon, solubilization of soil organic matter or shifts in soil pH. Our results indicate that OAs play a significant role in shaping soil bacterial communities and this may therefore have a significant impact on plant growth.},
	keywords = {Bacteria, DNA, Bacterial, Molecular Sequence Data, Organic Chemicals, Phylogeny, Pinus, Plant Exudates, Plant Roots, Rhizosphere, RNA, Ribosomal, 16S, Soil, Soil Microbiology},
	issn = {1574-6941},
	doi = {10.1111/j.1574-6941.2011.01150.x},
	author = {Shi, Shengjing and Richardson, Alan E and O{\textquoteright}Callaghan, Maureen and Deangelis, Kristen M and Jones, Eirian E and Stewart, Alison and Firestone, Mary K and Condron, Leo M}
}
@article {377,
	title = {Bacterial diversity analysis of Huanglongbing pathogen-infected citrus, using PhyloChip arrays and 16S rRNA gene clone library sequencing.},
	journal = {Appl Environ Microbiol},
	volume = {75},
	year = {2009},
	month = {2009 Mar},
	pages = {1566-74},
	abstract = {The bacterial diversity associated with citrus leaf midribs was characterized for citrus groves that contained the Huanglongbing (HLB) pathogen, which has yet to be cultivated in vitro. We employed a combination of high-density phylogenetic 16S rRNA gene microarrays and 16S rRNA gene clone library sequencing to determine the microbial community composition for symptomatic and asymptomatic citrus midribs. Our results revealed that citrus leaf midribs can support a diversity of microbes. PhyloChip analysis indicated that 47 orders of bacteria in 15 phyla were present in the citrus leaf midribs, while 20 orders in 8 phyla were observed with the cloning and sequencing method. PhyloChip arrays indicated that nine taxa were significantly more abundant in symptomatic midribs than in asymptomatic midribs. "Candidatus Liberibacter asiaticus" was detected at a very low level in asymptomatic plants but was over 200 times more abundant in symptomatic plants. The PhyloChip analysis results were further verified by sequencing 16S rRNA gene clone libraries, which indicated the dominance of "Candidatus Liberibacter asiaticus" in symptomatic leaves. These data implicate "Candidatus Liberibacter asiaticus" as the pathogen responsible for HLB disease.},
	keywords = {Bacteria, Biodiversity, Citrus, DNA, Bacterial, DNA, Ribosomal, Genes, rRNA, Microarray Analysis, Molecular Sequence Data, Phylogeny, Plant Diseases, Plant Leaves, Rhizobiaceae, RNA, Bacterial, RNA, Ribosomal, 16S, Sequence Analysis, DNA, Sequence Homology, Nucleic Acid},
	issn = {1098-5336},
	doi = {10.1128/AEM.02404-08},
	author = {Sagaram, Uma Shankar and Deangelis, Kristen M and Trivedi, Pankaj and Andersen, Gary L and Lu, Shi-En and Wang, Nian}
}
