Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Microbes help beetles defeat plant defenses

10.09.2013
Some symbiotic bacteria living inside Colorado potato beetles can trick plants into reacting to a microbial attack rather than that of a chewing herbivore, according to a team of Penn State researchers who found that the beetles with bacteria were healthier and grew better.

"For the last couple of decades, my lab has focused on induced defenses in plants," said Gary W. Felton, professor and head of entomology. "We had some clues that oral secretions of beetles suppressed defenses, but no one had followed up on that research."


This is a Colorado potato beetle larva.
Credit: Gary Felton, Penn State

Seung Ho Chung, graduate student in entomology working with Felton, decided to investigate how plants identified chewers and how herbivores subverted the plants defenses.

"I thought we could identify what was turning the anti-herbivore reaction off," said Felton. "But it was a lot more difficult because we had not considered microbes."

According to Felton, the beetles do not have salivary glands and so they regurgitate oral secretions onto the leaves to begin digestion. These secretions contain gut bacteria.

Plant defenses against chewing insects follow a jasmonite-mediated pathway that induces protease inhibitors and polyphenol oxidase, which suppress digestion and growth. Plant defenses against pathogens follow a salicylic acid mediated pathway. When the antimicrobial response turns on, it interferes with the response to chewing, allowing the beetles to develop more normally.

Chung and Felton used tomato plants to identify exactly what was turning off the response to chewing. They note, however, that the Colorado potato beetle also attacks eggplant and potato plants. They report the results of their work in the current online edition of the Proceedings of the National Academy of Sciences.

The researchers allowed beetle larva to feast on antibiotic-treated leaves and natural leaves and found that on the antibiotic-treated leaves, the beetles suffered from the plant's anti-herbivore defense, but on the natural leaves the larva gained more weight and thrived.

Chung and Felton then investigated expression of genes in the anti-herbivore pathway and the production of enzymes. They found that the presence of bacteria decreases the anti-herbivore response.

The researchers also isolated and grew the bacteria from the Colorado potato beetle guts. They found 22 different types of bacteria, but only three types suppressed the anti-herbivore response. During a variety of other experiments, they found that in all cases presence of the bacteria that could suppress the anti-herbivore response led to healthier beetles.

The researchers are now beginning to see if these bacteria are present in Colorado potato beetles all over the U.S. and also in Europe.

Also working on this project were Cristina Rosa, research associate in entomology; Erin D. Scully, graduate student in the intercollege program in genetics; Michelle Peiffer, research assistant in entomology; John F. Tooker, assistant professor of entomology; Kelli Hoover, professor of entomology and Dawn S. Luthe, professor of plant science.

The U.S. Department of Agriculture and the National Science Foundation supported this work.

A'ndrea Elyse Messer | EurekAlert!
Further information:
http://www.psu.edu

More articles from Life Sciences:

nachricht Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>