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Distribution of 'Ca. Liberibacter asiaticus' in infected sweet orange trees

Wenbin Li, Laurene Levy, and John S. Hartung

cartoon tree image depicting location and concentration of HLB within various parts of a citrus tree

An illustration of the distribution and population levels of the pathogen 'Ca. Liberibacter asiaticus' in a sweet orange infected by a bud graft and grown in a greenhouse. The colors indicate relative population densities from 10,000 cells/gram of tissue (navy blue) to 10,000,000 cells/gram of tissue (yellow) to 1,000,000,000 cells/gram of tissue (red). Notice that the mid-veins of the leaves are an excellent place to sample for bacteria. Notice also that the tree is completely infected, but that the populations of bacteria found in the tree varies greatly from site to site in the tree, which complicates sampling of trees for diagnostic tests.

Orange line

For more information about citrus pathogens please contact Dr. John Hartung

For more information concerning growing citrus please contact Cristina Paul


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