Duration: 10/01/2009 to 09/30/2010

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Statement of Issues and Justification

Tall fescue [Lolium arundinaceum (Schreb.) Darbysh. = Schedonorus arundinaceus (Schreb.) Dumort.] is a versatile cool-season grass extensively used for forage and turf (12). The first cultivar, Kentucky-31, released in the 1940s has been widely distributed across the USA. Tall fescue is well adapted to the transition zone (known as the fescue belt) that is considered colder than optimal for warm season grasses but hotter than optimal for other cool season grasses such as perennial ryegrass (12). The nutritive value, persistence, wide range of adaptation and ease of management has made tall fescue a popular forage that is now grown in the US on over 35 million acres.

Eventually it was determined that persistence of tall fescue was in part owing to the presence of a fungal endophyte, Neotyphodium coenophialum (2). The success of N. coenophialum within its host is due to a lifestyle strategy where the fungus systemically infects the aerial parts of the plant without causing disease, and is only transmitted in the seed. The endophyte provides many benefits to its host, but unfortunately produces alkaloids that cause toxicity to the grazing livestock resulting in annual production losses of over US$600 million (1). It has since been well documented that ergot alkaloids are the causative agent of fescue toxicosis which presents with numerous detrimental effects such as fescue foot, reproductive disorders, and reduced milk production and weight gains. It is now known that many cool-season grasses harbor fungal endophytes from the closely related genus Epichloë and Neotyphodium, which are collectively called epichloë endophytes or epichloae in the plural [reviewed by Clay and Schardl (4)]. Perennial ryegrass was found to contain the endophyte Neotyphodium lolii that is also capable of producing ergot alkaloids as well as lolitrem B, an indole-diterpene that causes ryegrass staggers (6).

Endophyte-free tall fescue cultivars were established in the mid-1980s to overcome the toxicity problems of their endophyte-infected counterparts, and while these provided the required animal production benefits, the pastures were not able to persist well (11, 14). The endophytes in the agriculturally important grasses, tall fescue and perennial ryegrass, provide their hosts with protection from biotic stresses, such as insect and pathogen resistance, as well as abiotic stresses, such as drought tolerance (7-9). Therefore, inclusion of endophytes in forage grasses, such as N. coenophialum in tall fescue and N. lolii in perennial ryegrass, is now considered important for grass breeding because of the beneficial properties they impart to the grass host.

Much research has been done to understand the association of epichloae endophytes and their grass hosts as well as the impact they can have on grazing livestock, and a number of strategies now exist to manage fescue toxicosis (10). These strategies range from dealing directly with the endophyte, such as re-infecting grasses with naturally occurring isolates that are unable to cause mammalian toxicity and thus impart only the beneficial features of the association (3, 5), to pasture and animal management practices that limit exposure to the alkaloids (13).

In 1984 the Southern Research Information Exchange Group (SRIEG-37, Fescue Toxicity) was formed to allow scientists to exchange research ideas and data relating to the fescue toxicosis problem. In 1990, this group co-hosted the first international endophyte symposium in Louisiana. The SRIEG-37 was later expanded to include extension, and now stands as the Southern Extension and Research Activity  Information Exchange Group (SERA-IEG8) for Fescue Endophyte Research and Extension. Participants of SERA-IEG8 are research scientists, extension specialists and industry representatives associated with fescue toxicosis problems, management, and research and development.

Objectives

Procedures and Activities

The purpose of SERA-IEG8 is to enhance our knowledge and understanding of endophytes, their grass hosts and the related animal toxicity problems they cause by exchanging research and extension information across a broad scientific group. Due to the complexity of the problem the group spans a wide-ranging array of disciplines that include: chemists, mycologist, plant breeders, agricultural economists, agronomists, ecologists, entomologists, genetic engineers, animal and plant physiologists, animal and plant geneticists, veterinarians, toxicologists, nutritionalists, extension specialists, and members of feed and seed industries. State representation currently includes university, federal, and foundation researchers and extension specialist from Arkansas, Georgia, Illinois, Kentucky, Louisiana, Mississippi, Oklahoma, Oregon, Missouri, South Carolina, and Tennessee; in previous years, it has also included Alabama, North Dakota, Texas, and Virginia. The annual meeting is attended by the above members as well as colleagues from industries within the US, and AgResearch, New Zealand, an International company with a strong agricultural and endophyte interest.

The function of SERA-IEG8 is to provide a way to enhance information exchange by bringing together this diverse group of people. SERA-IEG8 hosts an annual meeting in October to present state reports. These reports are provided as a comprehensive annual report document for all participants and can cover hot off the press unpublished data. Information on SERA-IEG8, including summary of previous state reports, can be found on the webpage http://animalscience.ag.utk.edu/SERA-IEG8/. Since 1990, members of SERA-IEG8 have been involved in six international endophyte meetings held in USA (Louisiana, 1990; Georgia, 1997; Arkansas, 2004), New Zealand (1993 and 2007), and Germany (2000) dedicated to epichloae-host interactions and their impact on agriculture. The 7th international meeting will be hosted by Dr Chris Schardl in Lexington, Kentucky.

Expected Outcomes and Impacts

Projected Participation

View Appendix E: Participation

Educational Plan

The meeting format is conducted as a state wide institution-by-institution presentation based on the submitted annual reports. Open discussion during the presentations are encouraged to help develop ideas and possible collaborations. Researchers are encouraged to review the problem to identify areas that need additional or new research approaches. The meeting is constructed to maximize the exchange of ideas and information. The annual reports are provided to participants as a printed bound document and as PDF, and a summary of these reports are publicly available at http://animalscience.ag.utk.edu/SERA-IEG8/. These reports often contain preliminary data that are frequently unaccompanied by publishable analyses and narratives.

Target Audiences: The primary target audience for this group is the group participant, since it is an information exchange group. Secondly the collaborators of the participants at their respective institutions. Thirdly, the programs of the participants and their collaborators influence in their respective institutions.

Organization/Governance

The SERA-IEG8 group elects an incoming secretary via committee selection and subsequent vote, who in the subsequent year will become the chairperson and meeting organizer. Meetings are held annually and include a business meeting for all attendees. The secretary will arrange collection and collation of the state reports to be presented at the annual meeting. Summary of reports are provided to the manager of the website as an available public record. Full reports are no longer maintained on the web page as these are non-refereed reports that do not include finalized narratives that will be submitted to referred journal. As such, these reports are not to be cited. Minutes are included in the proceeding years report.

Literature Cited

1. Allen, V. G. and E. Segarra. 2001. Anti-quality components in forage: Overview, significance, and economic impact. J. Range Manage. 54:409-412.

2. Bacon, C. W., J. K. Porter, J. D. Robbins, and E. S. Luttrell. 1977. Epichloë typhina from toxic tall fescue grasses. Appl. Environ. Microbiol. 34:576-581.

3. Bouton, J. H., G. C. M. Latch, N. S. Hill, C. S. Hoveland, M. A. McCann, R. H. Watson, J. A. Parish, L. L. Hawkins, and F. N. Thompson. 2002. Reinfection of tall fescue cultivars with non-ergot alkaloid-producing endophytes. Agron. J. 94:567-574.

4. Clay, K. and C. Schardl. 2002. Evolutionary origins and ecological consequences of endophyte symbiosis with grasses. Am. Nat. 160:S99-S127.

5. Fletcher, L. R. 1999. "Non-toxic" endophytes in ryegrass and their effect on livestock health and production, p. 133-139. In D. R. Woodfield and C. Matthew (ed.), Ryegrass endophyte: an essential New Zealand symbiosis. New Zealand Grassland Association, Napier, New Zealand.

6. Fletcher, L. R. and I. C. Harvey. 1981. An association of a Lolium endophyte with ryegrass staggers. N. Z. Vet. J. 29:185-186.

7. Johnson, M. C., D. L. Dahlman, M. R. Siegel, L. P. Bush, G. C. M. Latch, D. A. Potter, and D. R. Varney. 1985. Insect feeding deterrents in endophyte-infected Tall Fescue. Appl. Environ. Microbiol. 49:568-571.

8. Malinowski, D. P. and D. P. Belesky. 2000. Adaptations of endophyte-infected cool-season grasses to environmental stresses: mechanisms of drought and mineral stress tolerance. Crop Sci. 40:923-940.

9. Popay, A. J. and S. A. Bonos. 2005. Biotic responses in endophytic grasses., p. 163. In C. A. Roberts, C. P. West and D. E. Spiers (ed.), Neotyphodium in cool-season grasses. Blackwell Publishing, Ames, IA.

10. Roberts, C. and J. Andrae. 2004. Tall fescue toxicosis and management. Crop Management 1-17.

11. Siegel, M. R., G. C. M. Latch, and M. C. Johnson. 1985. Acremonium fungal endophytes of tall fescue and perennial ryegrass: Significance and control. Plant Dis. 69:179-181.

12. Sleper, D. A. and C. P. West. 1996. Tall Fescue, p. 475. In L. E. Moser, D. R. Buxton and M. D. Casler (ed.), Cool-season forage grasses. Agron. Monograph no. 34. ASA, CSSA, SSSA, Madison, WI.

13. Stuedemann, J. and D. Seman. 2005. Integrating genetics, environment, and management to minimize animal toxicoses, p. 305-326. In Anonymous Neotyphodium in cool-season grasses. Blackwell Publishing, Iowa.

14. Thompson, R. W., H. A. Fribourg, J. C. Waller, W. L. Sanders, J. H. Reynolds, J. M. Phillips, S. P. Schmidt, R. J. Crawford, V. G. Allen, and D. B. Faulkner. 1993. Combined analysis of tall fescue steer grazing studies in the Eastern United States. J. Anim. Sci. 71:1940-1946.

Attachments

Land Grant Participating States/Institutions

AL, FL, GA, IA, IN, KY, LA, MN, MS, NJ, OH, OR, SC, TN, TX, VA

Non Land Grant Participating States/Institutions

Samuel Roberts Noble Foundation, Texas Tech University