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78 GOLF COURSE MANAGEMENT 03.14 Disease updates Editor's note: Each year, GCM publishes reports of previously unknown diseases, sightings in areas where diseases have not been seen previously and other news of turfgrass diseases. The following reports were previously published in the journal Plant Disease. Patches of thinning buffalograss are the result of leaf blight caused by Curvularia and Bipolaris species in mid-summer in Lincoln, Neb. Photos by B.S. Amaradasa First report of Curvularia inaequalis and Bipolaris spicifera causing leaf blight of buffalograss in Nebraska Buffalograss (Buc loe dactyloides [Nutt.] Engelm.) is a warm-season turfgrass native to the mid-plains of North America having exceptional heat, cold and drought tolerance. In the past few decades, many turf-type buf - falograss cultivars have been commercially released. During the summer of 2011, foliar blight was observed on buffalograss lawns in Lincoln and Waverly, Neb. Disease symp - toms were common when buffalograss was growing above 86 F (30 C) and in drought conditions. Disease symptoms began as dark brown, oblong leaf spots, followed by leaf tip dieback and eventual blighting of entire tillers. Leaf infections would progress into patches of thinning turf. Diseased leaf pieces were cultured and observed under a microscope to identify the causal organisms. Two fungal species having conidial morphology of Curvularia and Bi - polaris were isolated. Colonies of Curvularia isolates grown on potato dextrose agar at 77 F (25 C) appeared velvety and dark green- ish to grayish black after one week, while Bipolaris cultures were brownish gray with olive-green margins. The two species were identifed as Curvularia inaequalis (Shear) Boedijn and Bipolaris spicifera (Bainier) Subram. Conidia of C. inaequalis were mostly straight to slightly curved, 17.4 to 37.1 × 7.2 to 12.6 micrometers, pale brown to brown, and three to four septate. Conidia of B. spic - ifera were 18.5 to 30.3 × 7 to 11.4 micro- meters, ellipsoidal or oblong, light brown and three-septate. DNA testing was used to confrm the identity of the two pathogens. Pathogenicity of the two species was tested on the buffalograss cultivar Prestige. Sto - lons of Prestige were established in 4-inch (10-centimeter) square pots flled with pot - ting medium. The pots of buffalograss were kept in an 86 F greenhouse with a 12-hour photoperiod for 12 weeks. One isolate of (Report) 078-095_March14_TechwellCuttingEdge.indd 78 2/18/14 1:46 PM