Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

First report of powdery mildew caused by Podosphaera fusca on Potentilla supina in China.

Abstract

During the spring and summer of 2013, a suspected powdery mildew was observed on Potentilla supina growing in 10 fields (approximately one hectare in total) in Shangqiu City in eastern Henan Province, China, with 60% of the plants being infected. Symptoms began as typical white powdery mildew colonies partially covering adaxial surfaces of leaves. As the disease progressed, all green parts (both adaxial and abaxial surfaces of leaves, stems, petioles, and calyxes) were covered with white mycelia and conidia. Newly emerged leaves rapidly became infected. The infected plants became yellow and necrotic at advanced stages of infection, and therefore lost their commercial value as medicine and food. Based on morphological characteristics, sequence analysis of the rDNA internal transcribed spacer region and pathogenicity tests, the causal agent was identified as Podosphaera fusca. Potentilla supina was previously described as the hosts of Sphaerotheca aphanis and Oidium spp. This is thought to be the first report of powdery mildew caused by Podosphaera fusca in China and will benefit the protection of Potentilla supina against powdery mildew.