First report of rough leaf spot of sorghum caused by Ascochyta sorghi in China.
In August 2015, long oval or irregular shaped and rough leaf lesions were observed on sorghum cv. Liaoza 19 in Fuxin city of Liaoning and Chifeng city of Nei Mongol, China. Early lesion development included small circular to oval spots with distinct margins. The centre of the spots was lighter in colour with a darker halo. Several lesions coalesced to form larger, distinct diseased areas on leaves. Numerous black, flask-shaped pycnidia were embedded on both sides of the lesion. The disease caused severe damage, killing leaves and was most destructive on lower leaves. Disease incidence reached 65%. The causal pathogen was identified as Ascochyta sorghi based on morphological, molecular and pathogenicity analyses. The obtained sequence was deposited in GenBank (accession no. MG525547). This is thought to be the first report of A. sorghi causing sorghum rough leaf spot in China in the modern era.