Navigation Links
Food security for leaf-cutting ants: Workers and their fungus garden reject endophyte invaders
Date:4/2/2009

New diseases directly affect human survival and food security, especially as population density climbs. Leaf-cutting ants, one of a few groups of social insects to cultivate crops, have harvested plant material to fertilize their underground fungal gardens for ~50 million years. New results from the Smithsonian show that both the ants and their fungal crop actively combat fungi coming into the nest inside leaves, thus ensuring the health of their mutualism.

"When you look at a healthy tropical plant, you think you're seeing just one organism, but each leaf can have dozens of fungal species growing inside, some of which may protect the plant by excluding pathogens," explains Sunshine Van Bael, post-doctoral fellow at the Smithsonian Tropical Research Institute. The fungi growing inside leaves without causing disease to the plant are called endophytes: endo-, inside, and phyte, plant.

"We knew that leaf cutter ants practice phenomenal garden hygiene. But we wondered if the fungi in leaves might make them less attractive to ants, and thereby protect the plant from leaf cutter ant invasion. Also, since most leaves in nature have endophytic fungi, we wondered how the ants' leaf preparation process might affect the passage of endophytes into the nest."

Van Bael and colleagues used laboratory colonies of one leaf cutter ant species, Atta colombica, to test the ants' response to leaves from a tropical vine, Merremia umbellata, in which they had experimentally manipulated the densities of one fungal endophyte species, Glomerella cingulata, in order to present the ants with leaves containing either high or low levels of fungus. They also pitted 32 additional endophytic fungal strains against cultures of the garden cultivar in Petri plates to find out if they would restrict each others' growth.

Ants cut leaves that contained both high or low levels of fungi, but they took longer to cut leaves from the high endophyte treatment. Moreover, the leaf preparation process by the ants significantly lowered the amount of fungi in leaf pieces before they were placed into the fungal garden. The Petri plate experiment also showed that the garden fungus reduced the growth rate for 28 of the 32 endophytic fungal strains that were tested, with a stronger effect for more rapidly growing endophyte strains. This suggests that, apart from the hygiene practiced by the ants, the garden itself can compete with incoming microbes.

"Fungi in the leaves were not welcome in the leaf cutter ants' garden," concluded Van Bael.

s," explains Sunshine Van Bael, post-doctoral fellow at the Smithsonian Tropical Research Institute. The fungi growing inside leaves without causing disease to the plant are called endophytes: endo-, inside, and phyte, plant.

"We knew that leaf cutter ants practice phenomenal garden hygiene. But we wondered if the fungi in leaves might make them less attractive to ants, and thereby protect the plant from leaf cutter ant invasion. Also, since most leaves in nature have endophytic fungi, we wondered how the ants' leaf preparation process might affect the passage of endophytes into the nest."

Van Bael and colleagues used laboratory colonies of one leaf cutter ant species, Atta colombica, to test the ants' response to leaves from a tropical vine, Merremia umbellata, in which they had experimentally manipulated the densities of one fungal endophyte species, Glomerella cingulata, in order to present the ants with leaves containing either high or low levels of fungus. They also pitted 32 additional endophytic fungal strains against cultures of the garden cultivar in Petri plates to find out if they would restrict each others' growth.

Ants cut leaves that contained both high or low levels of fungi, but they took longer to cut leaves from the high endophyte treatment. Moreover, the leaf preparation process by the ants significantly lowered the amount of fungi in leaf pieces before they were placed into the fungal garden. The Petri plate experiment also showed that the garden fungus reduced the growth rate for 28 of the 32 endophytic fungal strains that were tested, with a stronger effect for more rapidly growing endophyte strains. This suggests that, apart from the hygiene practiced by the ants, the garden itself can compete with incoming microbes.

"Fungi in the leaves were not welcome in the leaf cutter ants' garden," concluded Van Bael.


'/>"/>

Contact: Beth King
kingb@si.edu
7-034-873-770-8216
Smithsonian Tropical Research Institute
Source:Eurekalert  

Related biology news :

1. BIO-key(R) Granted Patent for Trusted Biometric Device Security Solution
2. Scientists gather to protect global food security from return of devastating wheat fungus
3. QSGI Integrates Fujitsu Mag EraSURE Data Degausser into its Suite of Information Technology Security Services
4. Fujitsu Develops HDD Security Technology Based on Opal SSC Standards
5. VUANCE Announces Crime Scene Security and Evidentiary Tracking Development Project
6. Nuclear science for food security
7. Halas wins high-profile national security award
8. Springer launches Food Security
9. USAID grant awarded to improve food security in Africa
10. Research conference at UH to focus on US troops needs, homeland security
11. bioMETRX, Inc. Welcomes Residential and Commercial Security Expert to Board of Directors
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Food security for leaf-cutting ants: Workers and their fungus garden reject endophyte invaders
(Date:3/22/2016)... 2016 According to ... for Consumer Industry by Type (Image, Motion, Pressure, ... & IT, Entertainment, Home Appliances, & Wearable ... 2022", published by MarketsandMarkets, the market for ... USD 26.76 Billion by 2022, at a ...
(Date:3/15/2016)... York , March 15, 2016 ... market report published by Transparency Market Research "Digital Door Lock ... and Forecast 2015 - 2023," the global digital door lock ... 731.9 Mn in 2014 and is forecast to grow at ... Growth of micro, small and medium enterprises (MSMEs) across the ...
(Date:3/11/2016)... 2016 --> ... "Image Recognition Market by Technology (Pattern Recognition), by Component ... Deployment Type (On-Premises and Cloud), by Industry Vertical and ... MarketsandMarkets, the global market is expected to grow from ... by 2020, at a CAGR of 19.1%. ...
Breaking Biology News(10 mins):
(Date:5/20/2016)... Raleigh, NC (PRWEB) , ... May 20, 2016 , ... ... cells, suggesting that it may offer a new way to treat the disease. Surviving ... read it now. , Scientists from several Korean institutions based their mesothelioma study ...
(Date:5/19/2016)... , May 19, 2016  AdvancedFlow Systems ... Inc. (AGI), based out of Maple ... Biogas Ltd. to its existing portfolio of contract ... agreement. AFS along with its sister companies Surround ... a vertically integrated industrial group that specializes in ...
(Date:5/19/2016)... DIEGO , May 19, 2016 ... (OTC PINK: RGBP) and (OTC PINK: RGBPP) announced today ... creating the first cord blood based cancer immunotherapeutic ... provisional patent application, Regen described a generation of ... was potentiated by gene silencing.  The product in ...
(Date:5/18/2016)... , ... May 18, 2016 , ... ... Sciences Summer Camp at The University of Toledo. This two-day camp will take ... opportunity to explore the field of pharmaceutical sciences in preparation for a university ...
Breaking Biology Technology: