Susceptibility of Chewings Fescue and Hard Fescue to Anthracnose Disease Caused by Colletotrichum cereale

Abstract

Anthracnose, caused by the fungal pathogen Colletotrichum cereale Manns sensu lato Crouch, Clarke & Hillman, can be a damaging disease on many cool-season turfgrasses; however, it has not been reported as an aggressive pathogen on fine fescue species (Festuca spp.). Symptoms and signs associated with anthracnose disease were observed in fine fescues on the Rutgers University Plant Science Research and Extension Farm in Adelphia, NJ, in Jun 2014. The objectives of this study were to identify the causal agent, determine if the isolate of C. cereale (FF1A) obtained from symptomatic Chewings fescue (Festuca rubra L. ssp. commutata Gaudin) plants was pathogenic to Chewings fescue and hard fescue (F. brevipila Tracey) turfs, and whether cultivars and accessions collected from Europe varied in disease susceptibility. Pathogenicity of this fine fescue isolate was evaluated using four Chewings fescue and four hard fescue cultivars or accessions in a growth chamber. Disease symptoms were first observed at 5 days post-inoculation, and evaluations continued to 17 days post-inoculation. Infection was confirmed by morphological evaluations, re-isolation from symptomatic tissues, and real-time polymerase chain reaction (PCR). Three noncommercial accessions (two Chewings fescues and one hard fescue) were very susceptible to the fine fescue C. cereale FF1A isolate, whereas ‘Sword’ and ‘Beacon’ hard fescues exhibited low susceptibility. In addition, an isolate of C. cereale (HF217CS) from annual bluegrass [Poa annua L. f. reptans (Hausskn) T. Koyama] was included, and our data demonstrated that this isolate was also able to infect Chewings fescue and hard fescue. This study confirmed that C. cereale can be a damaging pathogen of fine fescues, and that breeding for resistance to anthracnose should be considered when developing new cultivars.