Evidence of Occurrence of Barley Crown Rust Caused by Puccinia coronata var. hordei and Sexual Reproduction of the Pathogen Under Field Conditions in China

Abstract

Crown rust of barley, caused by Puccinia coronata var. hordei (Pch), was first reported by Jin and Steffenson in 1992, and the fungus has been reported only in the United States and Hungary. In China, stripe, stem, and leaf rusts have been reported on barley, but not for crown rust. Recently, a sample (HZJ0004) of rust collected from barley in Qilian county, Qinghai, China, appeared different from the three rusts based on color, size, arrangements of uredinia and/or telia. Teliospores had crown-shaped appendages on the top. Based on the disease symptoms and morphology of urediniospores and teliospores, the fungus was identified as Pch. Using the internal transcribed spacer sequences, the isolates HZJ0004 from barley and POR3 from buckthorn (Rhamnus sp.) were clustered in one clade with Pch isolates from barley and Elymus repens but in a different clade from the isolate POC8 from wild oat and the varieties of P. coronata from oats and grasses. At the seedling stage, most of the tested cultivars of barley and rye were susceptible to Pch isolates HZJ0004 and POR3, but the cultivars of oats, triticale, wheat, and the most grasses of Aegilops, Brachypodium, Bromus, Calamagrostis, Deschampsia, Elymus, Festuca, and Phleum were resistant, indicating their host specialization on barley. This is the first report of crown rust on barley in China.

Micromycetes associated with barley and their significance as pathogens in Russia

“…Заболевание распространено на овсе. На ячмене оно было зарегистрировано в единичных случаях в США, Венгрии и Китае (Tian et al, 2021).…”