What is in this article?:
- Scent of citrus greening infected trees attracts psyllids
- Don’t taste right
• When the pests encounter a faint whiff of methyl salicylate they interpret it to mean that other psyllids have found a good place to feed, and hurry to join the banquet.
• One experiment in the study showed that psyllids were more likely to land on infected citrus trees than healthy ones.
UNIVERSITY OF FLORIDA researcher Lukasz Stelinski, was part of a team that determined the citrus greening bacterium causes infected trees to give off a fragrant chemical called methyl salicylate. The chemical attracts the Asian citrus psyllid, the insect responsible for spreading the disease.
Don’t taste right
“We believe they (the infected trees) don’t taste right to the psyllids,” said Stelinski, at UF’s Citrus Research and Education Center in Lake Alfred.
But even a short feeding session is enough for the invasive insects to suck up the greening bacterium, along with the plant sap they consume. When the psyllids fly to healthy trees and resume feeding, they’re likely to infect those trees.
The good news is that methyl salicylate is inexpensive and widely available, so it could be used to battle greening. For example, it could be put in traps used to monitor groves for the presence of psyllids, to attract the pests.
Another possibility: If methyl salicylate were released in small amounts throughout a citrus grove, the pervasive odor could camouflage infected trees’ scent. This strategy could reduce the chance that psyllids converge on infected trees, by making it appear that all trees were ringing the dinner bell.
Stelinski said he plans to pursue both ideas in future studies.
The psyllid is native to southern Asia and was first identified in Florida in 1998. The tiny insect initially caused problems by stunting tree growth and promoting mold infections.
Citrus greening disease is the most serious threat to Florida’s $9 billion citrus industry. The disease weakens and eventually kills infected trees, and currently there is no cure.
According to a UF study, greening has cost the state $3.63 billion since 2006, stemming from crop losses and loss of income to growers and citrus-related businesses.
Other members of the study team were Rajinder Mann, Jared Ali, Sara Hermann, Siddharth Tiwari and Kirsten Pelz-Stelinski, all at the Lake Alfred center, and Hans Alborn of the U.S. Department of Agriculture’s Center for Medical, Agricultural and Veterinary Entomology in Gainesville.