@article{tredway_butler_2007, title={First report of spring dead spot of zoysiagrass caused by Ophiosphaerella korrae in the United States}, volume={91}, ISSN={["1943-7692"]}, DOI={10.1094/PDIS-91-12-1684A}, abstractNote={ Since 2002, symptoms of an unknown disease have been observed in ‘El Toro’ zoysiagrass (Zoysia japonica Steud.) in several locations across North Carolina. Symptoms become evident in the spring as the zoysiagrass comes out of winter dormancy. Circular or irregularly shaped patches, 10 to 30 cm in diameter, remain dormant as the surrounding turf resumes growth. These patches eventually collapse and die, leaving sunken depressions in the turf stand. After the initial appearance of symptoms, the zoysiagrass slowly recolonizes the patches by spreading inward from the perimeter. Microscopic observation revealed necrotic stolon and root tissue that was colonized by ectotrophic fungal hyphae, whereas leaf and sheath tissue was colonized by species of Curvularia, Colletotrichum, Alternaria, Ascochyta, Drechslera, or Fusarium. Sections of necrotic root and stolon tissue were washed under flowing tap water for 10 min, submersed in 0.6% NaOCl for 5 min, rinsed with sterile dH2O, blotted dry, and placed on ¼ strength potato dextrose agar amended with 100 μg/ml each of streptomycin sulfate and chloramphenicol. A total of 50 isolates were obtained from four locations during 2002 and 2003. A fungus resembling Ophiosphaerella spp. was consistently isolated and was confirmed to be Ophiosphaerella korrae by species-specific PCR assays (3) and rDNA internal transcribed spacer (ITS) sequencing. Pathogenicity tests were conducted in the field on ‘El Toro’ zoysiagrass at the Lake Wheeler Turfgrass Field Laboratory in Raleigh, NC. Autoclaved rye grain (Secale cereale L.; 200 g of grain, 5.75 g of CaCO3, and 220 ml of H2O) was infested with one of eight O. korrae isolates. Plots (1 × 1 m) were inoculated on 13 October 2004 by removing an 11-cm-diameter core from the center of each plot to a 5-cm depth, placing 10 cm3 of infested rye grain in the bottom of the hole, and replacing the core. Noninoculated and uninfested rye grain treatments served as controls, and each treatment was replicated eight times in a randomized complete block. No symptoms were observed in the experimental area during 2005. In April 2006, five isolates (Zrr20, Zrr36, Zrr57, Zrr58, and Zrr59) incited spring dead spot symptoms in at least four of eight inoculated plots. The average diameter of patches induced by these isolates ranged from 7.9 to 11.4 cm. In April 2007, three isolates (Zrr20, Zrr36, and Zrr57) incited symptoms in at least four plots, with average patch diameters ranging from 14.5 to 16.0 cm. These inoculation success rates and patch diameters were similar to those resulting from O. korrae inoculation of bermudagrass conducted on the same date (L. P. Tredway, unpublished data). No symptoms were observed in noninoculated plots or those amended with uninfested rye grain. O. korrae was consistently reisolated from symptomatic stolons and roots in May 2007 to complete Koch's postulates. To the best of our knowledge, this is the first report of spring dead spot of zoysiagrass caused by O. korrae in the United States. Previously, O. herpotricha was shown to induce spring dead spot symptoms on zoysiagrass in Kansas (1), and O. korrae was reported as a zoysiagrass pathogen in Japan (2). To date, we have only observed spring dead spot on the Zoysia japonica ‘El Toro’. }, number={12}, journal={PLANT DISEASE}, author={Tredway, L. P. and Butler, E. L.}, year={2007}, month={Dec}, pages={1684–1684} }
 @article{butler_tredway_2006, title={Method and timing of fungicide applications for control of spring dead spot in hybrid bermudagrass}, ISBN={1535-1025}, DOI={10.1094/php-2006-0901-01-rs}, abstractNote={ The efficacy of five application methods and four fungicides were evaluated for control of spring dead spot (SDS) of bermudagrass from 2002 to 2004. Fenarimol and propiconazole were most effective in reducing SDS, providing from 66% to 89% and 51% to 52% control, respectively. Application water volume (2.5, 5, or 10 gal/1000 ft2), post-application irrigation, and high-pressure injection did not affect SDS control. Further research with fenarimol was conducted from 2003 into 2005 to optimize application rate and timing. In both years, all rates (6, 4 + 4, and 6 + 6 fl oz/1000 ft2, with split applications 2 weeks apart) provided equivalent control of SDS when averaged across all application timings. No significant differences were detected among application timings ranging from August 1 to October 1 in 2003 and from August 23 to November 5 in 2004. }, journal={Plant Health Progress}, author={Butler, E. L. and Tredway, L. P.}, year={2006}, pages={1} }
 @article{butler_tredway_2005, title={Comparison of methods for evaluation of spring dead spot incidence in hybrid bermudagrass}, volume={10}, journal={International Turfgrass Society Research Journal}, author={Butler, E. L. and Tredway, L. P.}, year={2005}, pages={273} }
 @article{reynolds_butler_wetzel_bruneau_tredway_2005, title={Performance of Kentucky bluegrass-tall fescue mixtures in the Southeastern United States}, volume={10}, journal={International Turfgrass Society Research Journal}, author={Reynolds, W. C. and Butler, E. L. and Wetzel, H. C. and Bruneau, A. H. and Tredway, L. P.}, year={2005}, pages={525} }
 @article{butler_fernandez_louws_2002, title={Strawberry plant growth parameters and yield among transplants of different types and from different geographic sources, grown in a plasticulture system}, volume={12}, number={1}, journal={HortTechnology}, author={Butler, L. M. and Fernandez, G. E. and Louws, F. J.}, year={2002}, pages={100–103} }
 @article{fernandez_butler_louws_2001, title={Strawberry growth and development in an annual plasticulture system}, volume={36}, number={7}, journal={HortScience}, author={Fernandez, G. E. and Butler, L. M. and Louws, F. J.}, year={2001}, pages={1219–1223} }