Fungus Among Us

amberroses · March 17, 2010

I just saw this article about how fungi can transfer their tomato killing genes from one species to another. Dirty Fungus!

http://www1.umn.edu/news/news-releas...NT_181265.html

News Release

University of Minnesota study: Fungus can attack crops in unexpected way

MINNEAPOLIS / ST. PAUL (03/17/2010) —The disease attacking your tomato plants this summer may have migrated from a completely unrelated fungus, according to a University of Minnesota study.

The study, published this week in the journal Nature, found that fungi are more adaptable than previously thought and may "horizontally" transfer genes. The process is similar to the way bacteria quickly develop antibiotic resistance or obtain toxins. The transfer process, discovered in the university's plant pathology department, had previously been unknown.

Corby Kistler, an adjunct professor at the university and a scientist for the U.S. Department of Agriculture, was part of an international research group that discovered the ability to cause tomato wilt disease in the microscopic soil fungus known as Fusarium oxysporum is carried on special chromosomes that can easily move between fungal strains. Kistler and his colleagues discovered these new chromosomes during a USDA-funded project that compared the genomes of three species of Fusarium fungus that cause disease on different plants, including the tomato wilt fungus.

"When we did the comparison, we saw that the tomato strain had 11 chromosomes very similar to the other fungi, but then an additional four chromosomes that looked like nothing we'd ever seen before," Kistler said. "These chromosomes had many features that made them look like they came from a completely different species." Further examination of these chromosomes also showed them packed with genes involved in making the fungus a plant pathogen and so they quickly were named "pathogenicity chromosomes" by Kistler and his colleagues.

The discovery gives fresh perspective on reports of new pathogenic races of the wilt fungus arising rapidly in tomato fields. While it is clear these new pathogens may arise due to horizontal transfer of pathogenicity chromosomes, the exact process by which they move is still unknown.

"Growing healthy plants, whether as a farmer or a home gardener, is about staying one step ahead of pathogens," Kistler said. "Because of this work, we know more about the toolbox fungi have to cause disease. Our job now is to develop tools of our own aimed at those traits that make fungi harmful to plants."

Contacts: Becky Beyers, College of Food, Agricultural and Natural Resource Sciences, bbeyers@umn.edu, (612) 626-5754
Patty Mattern, University News Service, mattern@umn.edu, (612) 624-2801

**Mischka** · March 17, 2010

Interesting piece, indeed. This might explain a lot, too. Thanks for posting it!

March 17, 2010	#1
amberroses Tomatovillian™ Join Date: Feb 2010 Location: Florida Posts: 105	Fungus Among Us I just saw this article about how fungi can transfer their tomato killing genes from one species to another. Dirty Fungus! http://www1.umn.edu/news/news-releas...NT_181265.html News Release University of Minnesota study: Fungus can attack crops in unexpected way MINNEAPOLIS / ST. PAUL (03/17/2010) —The disease attacking your tomato plants this summer may have migrated from a completely unrelated fungus, according to a University of Minnesota study. The study, published this week in the journal Nature, found that fungi are more adaptable than previously thought and may "horizontally" transfer genes. The process is similar to the way bacteria quickly develop antibiotic resistance or obtain toxins. The transfer process, discovered in the university's plant pathology department, had previously been unknown. Corby Kistler, an adjunct professor at the university and a scientist for the U.S. Department of Agriculture, was part of an international research group that discovered the ability to cause tomato wilt disease in the microscopic soil fungus known as Fusarium oxysporum is carried on special chromosomes that can easily move between fungal strains. Kistler and his colleagues discovered these new chromosomes during a USDA-funded project that compared the genomes of three species of Fusarium fungus that cause disease on different plants, including the tomato wilt fungus. "When we did the comparison, we saw that the tomato strain had 11 chromosomes very similar to the other fungi, but then an additional four chromosomes that looked like nothing we'd ever seen before," Kistler said. "These chromosomes had many features that made them look like they came from a completely different species." Further examination of these chromosomes also showed them packed with genes involved in making the fungus a plant pathogen and so they quickly were named "pathogenicity chromosomes" by Kistler and his colleagues. The discovery gives fresh perspective on reports of new pathogenic races of the wilt fungus arising rapidly in tomato fields. While it is clear these new pathogens may arise due to horizontal transfer of pathogenicity chromosomes, the exact process by which they move is still unknown. "Growing healthy plants, whether as a farmer or a home gardener, is about staying one step ahead of pathogens," Kistler said. "Because of this work, we know more about the toolbox fungi have to cause disease. Our job now is to develop tools of our own aimed at those traits that make fungi harmful to plants." Contacts: Becky Beyers, College of Food, Agricultural and Natural Resource Sciences, bbeyers@umn.edu, (612) 626-5754 Patty Mattern, University News Service, mattern@umn.edu, (612) 624-2801

March 17, 2010	#2
Mischka Tomatoville® Administrator Join Date: Jan 2006 Location: The Bay State Posts: 3,207	Interesting piece, indeed. This might explain a lot, too. Thanks for posting it! __________________ Mischka One last word of farewell, Dear Master and Mistress. Whenever you visit my grave, say to yourselves with regret but also with happiness in your hearts at the remembrance of my long happy life with you: "Here lies one who loved us and whom we loved." No matter how deep my sleep I shall hear you, and not all the power of death can keep my spirit from wagging a grateful tail.