First Report of Colletotrichum karstii Causing Anthracnose on Nandina domestica in Henan Province, China

Abstract

Nandina domestica is widely cultivated as an urban ornamental tree in China. In May 2016, a leaf blight was observed on N. domestica in Luopu park of Luoyang (34°36′N, 112°24′E), Henan Province, China. Affected leaves exhibited necrotic lesions beginning at the leaf apex. The necrotic lesions began in early May, enlarged over two to three weeks after infection, finally resulting in leaf blight and defoliation. Disease incidence averaged 25% (n=40 plants). To isolate the pathogen, symptomatic leaves from 3 plants were cut into 0.5 cm2 pieces, surface disinfested in 70% ethanol for 30 s, washed once with sterile distilled water (SDW), then surface disinfested in 1% sodium hypochlorite for 5 min, followed by three rinses with SDW. Pieces were plated on potato dextrose agar (PDA) and incubated at 26°C under a 12-h light/dark cycle. After 2 days, a fungus with white aerial mycelium was consistently isolated . Colonies were flat, with a white margin that became grey with age, usually with pink conidial masses, ...