First report of Puccinia oxalidis on Oxalis triangularis from Iran

Oxalis triangularis A. St.-Hil. (Oxalidaceae) known as “False Shamrock”, is a perennial ornamental plant native to Brazil. The plant is used as indoor pot plant in Iran. In June 2018, rust-infected leaves were sampled from an indoor pot plant in University of Maragheh, located in Maragheh, East Azarbaijan. The following morphological features were observed on infected leaves: * Corresponding author’s E-mail: puccinia@gmail.com 1. Research Associate Prof., Department of Botany, Iranian Research Institute of Plant Protection, Agricultural Research, Education and Extension Organization (AREEO), Tehran 2. Instructor and Assistant Prof., of Department of Plant Protection, Faculty of Agriculture, University of Maragheh, Maragheh, Iran Spermogonia and aecia not seen. Uredinia round, 0.2-0.4 mm in diameter, in orbicular groups forming concentric circles up to 9 mm in diameter, soon naked, erumpent, powdery, yellowish white to orange-yellow, without paraphyses, urediniospores 16-23 × 13-19 µm, ellipsoid, globoid or obovoid, wall 0.5-1(1.5) µm thick, minutely and densely echinulate, colorless, germ pores obscure. Telia not seen, teliospores were sporadically present in uredinia, 21-28 × 15-18 µm, ellipsoid, oblong or broadly oblong, rounded or obtuse at apex, slightly constricted at septum, wall quite colorless, smooth, thin, 0.5-0.8 µm, pedicel colorless, as long as spores or shorter (Fig. 1).