Researchers from the University of Florida (UF) have discovered that citrus
greening attacks plant roots long before the leaves show signs of damage.
Evan Johnson, a research assistant scientist with UF's Institute of Food and
Agricultural Sciences, said "The role of root infection by insect-carried
bacterial pathogens has been greatly underestimated."

Citrus greening enters the tree when the insect Asian citrus psyllid sucks
on leaf sap and leaves behind bacteria that spread through the tree.
According to Johnson, the bacteria travel quickly to the roots, where they
replicate, damage the root system and spread to the rest of the host tree's
canopy. Although it was originally thought that the leaves and fruit were
affected first, the team's research found that greening causes a loss of 30
to 50 percent of trees' fibrous roots before symptoms are visible above
ground.

Experts say the research is a significant development in the fight against
citrus greening, and though it is not a cure, it may help more trees survive
as scientists continue their research.

[news.ufl.edu]