Variability of Ergovaline in Seeds and Straw and Endophyte Infection in Seeds Among Endophyte-Infected Genotypes of Tall Fescue. R. E. WELTY, Agricultural Research Service, U.S. Department of Agriculture, National Forage Seed Production Research Center and College of Veterinary Medicine, Oregon State University, Corvallis 97331-7102. A. M. CRAIG, and M. D. AZEVEDO, Agricultural Research Service, U.S. Department of Agriculture, National Forage Seed Production Research Center and College of Veterinary Medicine, Oregon State University, Corvallis 97331-7102. Plant Dis. 78:845-849. Accepted for publication 20 June 1994. This article is in the public domain and not copyrightable. II may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1994. DOI: 10.1094/PD-78-0845.

Individual plant genotypes of tall fescue (Festuca arundinacea) cultivar Kentucky 31 infected (E+) or not infected (E—) by the endophyte Acreinonium coenophialum growing for 2 yr in field plots were evaluated for ergovaline in seeds and straw and for percent endophyte infection in seeds. Ergovalirife (analyzed by HPLC) in straw from 25 E+ genotypes ranged from 8 to 1,268 ng/g in 1991 and from 0 to 478 ng/g in 1992; mean ergovaline concentration in straw from E+ genotypes in 1991 (292 ng/g) differed (F value = 7.42, P = 0.008) from that in 1992 (130 ng/g). Ergovaline concentration in seed ranged from 2 to 6,064 ng/g in 1991 and from 3 to 8,659 ng/g in 1992; mean ergovaline concentration in seeds from E+ genotypes was similar (F value = 0.21) in 1991 (2,509 ng/g) and 1992 (2,295 ng/g). Percent endophytc-infected seeds (stained and examined microscopically) among E+ genotypes was variable and ranged from 2 to 100% in 1991 and from 0 to 100% in 1992, but means were statistically similar {F value = 0.2) between years (84% in 1991 and 80% in 1992). This study provides evidence that among E+ genotypes of tall fescue growing in the field, variation exists in production of ergovaline and percent endophyte-infected seed. Furthermore, ergovaline in straw from E+ genotypes varies between years.

Keyword(s): ergopeptides