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Endophytes provide improved insect resistance to many turfgrass species, however their association with improved disease resistance has not been frequently reported. Red thread and pink patch caused by Laetisaria fuciformis (McAlp.) Burdsall and Limnomyces roseipellis Stalpers & Loerakker, respectively, are the most important diseases affecting the turf performance of fine fescue species. A study was initiated to determine the effects of different endophyte sources in strong creeping red fescue (Festuca rubra L. subsp. rubra) and Chewings fescue (Festuca rubra L. subsp. fallax (Thuill) Nyman). Five fine fescue genotypes (two strong creeping red fescue and three Chewings fescue) were inoculated with different endophytes originating from fine fescues and Poa ampla Merr. Progeny turf plots of each endophyte‐host genotype combination along with corresponding non‐endophyte‐infected genotypes were established in a mowed turf evaluation trial in September 1997 at Adelphia, NJ. The experiment was arranged in a randomized complete block design with three replications. A natural outbreak of red thread occurred in both spring 2001 and 2002. Turf quality (which utilized a 1 to 9 scale, 9 representing best turf quality) and percent red thread were evaluated in both years. Significant differences in red thread severity were observed between endophyte‐infected and endophyte‐free plots within the same host genotype. For three genotypes (1090, 1117, and 1139) at least one endophyte source significantly reduced red thread severity in both 2001 and 2002. In 2002, all endophyte sources significantly reduced red thread severity in these three genotypes. Different endophyte sources had different effects on red thread depending on the genotype inoculated. The Rose City endophyte showed the most consistent reduction in red thread severity, in several host genotypes, compared to other endophyte sources. This finding suggests that utilizing Chewings and strong creeping red fescue infected with endophytes may help suppress red thread and improve turf quality in addition to the documented improved insect resistance.

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Anisogramma anomala (Peck) E. Müller is the causal agent of the disease eastern filbert blight (EFB) of hazelnuts (Corylus spp.). Little is known of its genetic diversity and pathogenic variation. Most sources of host resistance have been identified in the Pacific Northwest, a region outside the native range of A. anomala believed to have limited diversity of the fungus due to a long history of quarantine and its relatively recent inadvertent introduction. In an attempt to investigate the pathogenic variation of A. anomala, 12 hazelnut genotypes that showed complete resistance in Oregon were inoculated with 12 isolates collected from across its native range. At the conclusion of the study, ‘Grand Traverse,’ ‘Ratoli’, OSU 541.147, OSU 495.072, and OSU 526.041 remained free of disease. ‘Closca Molla’, OSU 759.007, and OSU 587.044 were infected by most isolates. ‘Gasaway’ was infected by the Michigan isolate, which was also the only one to infect its offspring ‘Zimmerman’, although the lesion lacked sporulating stromata. Interestingly, ‘VR20–11’, another offspring of ‘Gasaway’, was infected by isolates from New Jersey, Minnesota, and Michigan. The Michigan isolate also caused the only signs of infection on OSU 408.040.