A. Ishaq, N.S. Afshan, A.N. Khalid
doi: 10.4454/JPP.V97I1.053
During an uredinological survey carried out in August 2009 in Sharan (Khyber Pakhtunkhwa province of Pakistan), leaves of Stipa sibirica infected with a rust fungus were found. Uredinia were abaxial, brown, 0.2 to 0.25 mm wide and 0.08 to 0.12 mm long. Urediniospores were globose to subglobose, hyaline, 18-24 × 21-28 μm in size, with 1.5-2.5 μm thick echinulated wall, and up to 5 scattered germ pores. Telia were abaxial and measured 0.1-0.2 × 0.07-0.09 mm. Teliospores were 1-2 celled with a prevalence of the 2-celled ones. They were oblong to clavate, hyaline to light brown, had 2-5 digitations, were 14- 19 × 38-57 μm long excluding digitations, and 36-68 μm long including digitations, 3-6 μm thick apically excluding the crown (7-20 μm thick including the crown). Spore walls were 2-3 μm thick. Based on these morphological traits and spore dimensions, the rust was identified as Puccinia coronata var. coronata, a sample of which was deposited in LAH Herbarium (LAH Herbarium No. AM1175) of the University of the Punjab, Lahore. P. coronata var. coronata has previously been recorded in Pakistan on Agrostis gigantea, Festuca sp., Lolium persicum and Themeda anathera (Ahmad et al., 1997; Afshan et al., 2011) but, to the best of our knowledge, this its first report on S. sibirica in this country.