Screening Tall Fescue Ecotypes for Brown Patch Resistance.

Tall fescue (Festuca arundinacea Shreb.) is primarily planted as a permanent species in home lawns and roadsides in the transition zone of the United States.  However, brown patch (Rhizoctonia solani Kuhn.) is a disease that can be devastating to permanent stands of tall fescue.  Wild ecotypes of tall fescue can be found growing throughout the north and central regions of Mississippi.  Therefore, the objective of this research was to determine if wild germplasm varied in resistance to brown patch.  If so, resistant genotypes could be used in future cultivar development for improved brown patch tolerance.  In 2013, tall fescue ecotypes were collected from cemeteries in central, MS where centipedegrass (Eremochloa ophiuroides [Munro.] Hack.) was the predominant species of mowed turf.  Thirty six genotypes, including four standard cultivars, and 32 ecotypes were inoculated with Rhizoctonia solani Kuhn. and maintained in a controlled greenhouse environment conducive to disease development.  Plants were rated weekly using a 1 to 9 scale. Statistical analysis of area under disease progress curve (AUDPC) revealed significant differences among genotypes for severity of brown patch symptoms.  Some ecotypes displayed resistance equal to or higher than proven standard cultivars.  Broad sense heritability for brown patch resistance in the first year’s collection and screening was 0.64.