Species communicate near infected citrus trees

decrease font size  Resize text   increase font size       Printer-friendly version of this article Printer-friendly version of this article

Four species communicate with and sometimes trick each other around a scent produced by greening-infected citrus trees, a new University of Florida study finds.

Communication between species is common but almost always is described between two or three species, said Lukasz Stelinski, associate professor of entomology and nematology at the Citrus Research and Education Center in Lake Alfred.

Stelinski wanted know how a fourth species, in this case, a wasp, would vary this interaction ─  a probe that may be one of the few cases where species at four levels of the food chain use one odor to communicate with, and exploit, each other.

Psyllids carry the pathogen that causes citrus greening, which has caused great damage to Florida’s $9 billion citrus industry. Stelinski’s team found that wasps and psyllids are both attracted to the odor emitted by an infected citrus tree. This olfactory cue may then help wasps find and prey on the psyillid by “eavesdropping” on the odor exchanged between bacteria, citrus trees and the psyllid.

The findings were published online by Frontiers in Ecology and Evolution.

Here’s how the interaction works: When host citrus trees are infected, they emit an odor, Stelinski said. That odor, methyl salicylate, makes them smell more appealing to the vector, the Asian citrus psyllid. Lured by scent, the tiny insect goes to the infected tree, searching for sap to snack on.

The hungry psyllid is attracted to the infected tree, even though pathogen-infected trees are less nutritious to psyllids than healthy ones.

 “This may be a mechanism, among many, that encourages the spread of the pathogen,” Stelinski said.

Stelinski’s team brought a wildcard, a wasp, into the mix because it’s a natural psyllid enemy. They wondered whether the wasp is also attracted to the methyl salicylate, as it hunts for psyllids to eat. So they put wasps in an olfactometer, a Y-shaped device that delivers two opposing air flows, each carrying a different odor.

The wasps could fly toward methyl salicylate or to a control odor, limonene, another compound produced by citrus trees. The wasps were strongly attracted by the pathogen-induced scent, methyl salicylate. They later learned the wasp was more likely to attack psyllids on greening-infected plants or methyl salicylate-treated plants rather than healthy plants.

“Biologically, we think it’s very interesting,” Stelinski said. “You to have to look at multiple levels of the food chain. The pathogen is manipulating the plant to attract the good guy and the bad guy. The finding makes the tree look like a beacon in a sea of uninfected trees.”

Stelinksi wrote the paper with Xavier Martini, a postdoctoral associate and Kirsten Pelz-Stelinksi, an associate professor of entomology, both at CREC.

Buyers Guide

Doyle Equipment Manufacturing Co.
Doyle Equipment Manufacturing prides themselves as being “The King of the Rotary’s” with their Direct Drive Rotary Blend Systems. With numerous setup possibilities and sizes, ranging from a  more...
A.J. Sackett Sons & Company
Sackett Blend Towers feature the H.I.M, High Intensity Mixer, the next generation of blending and coating technology which supports Precision Fertilizer Blending®. Its unique design allows  more...
R&R Manufacturing Inc.
The R&R Minuteman Blend System is the original proven performer. Fast, precise blending with a compact foot print. Significantly lower horsepower requirement. Low inload height with large  more...
Junge Control Inc.
Junge Control Inc. creates state-of-the-art product blending and measuring solutions that allow you to totally maximize operating efficiency with amazing accuracy and repeatability, superior  more...
Yargus Manufacturing
The flagship blending system for the Layco product line is the fully automated Layco DW System™. The advanced technology of the Layco DW (Declining Weight) system results in a blending  more...
Yargus Manufacturing
The LAYCOTE™ Automated Coating System provides a new level of coating accuracy for a stand-alone coating system or for coating (impregnating) in an automated blending system. The unique  more...
John Deere
The DN345 Drawn Dry Spreader can carry more than 12 tons of fertilizer and 17.5 tons of lime. Designed to operate at field speeds up to 20 MPH with full loads and the G4 spreader uniformly  more...
Force Unlimited
The Pro-Force is a multi-purpose spreader with a wider apron and steeper sides. Our Pro-Force has the most aggressive 30” spinner on the market, and is capable of spreading higher rates of  more...
BBI Spreaders
MagnaSpread 2 & MagnaSpread 3 — With BBI’s patented multi-bin technology, these spreaders operate multiple hoppers guided by independent, variable-rate technology. These models are built on  more...

Comments (0) Leave a comment 

e-Mail (required)


characters left

LPV Seed Treater

The LPV Seed Treater has set a new standard boasting three configurable weighing methods for any-sized operation, a standard 42” ... Read More

View all Products in this segment

View All Buyers Guides

Feedback Form
Feedback Form