Neofusicoccum parvum, agent of leaf spot on the new host Ginkgo biloba in Iran

摘要

Ginkgo (Ginkgo biloba) is increasingly popular as a street, park and specimen tree in Iran. Historically, it is very ancient having fossils recognisably related to modern ginkgo from the Permian Period, dating back 270 million years ago. In September and October 2013, a moderately severe leaf spot was observed on ginkgo cultivated in some parks and green spaces in Sari, Iran (Mazandaran province). Considerable defoliation was noted with approximately 50% of the trees showing symptoms. Spots originate as water-soaked patches and then develop into irregular areas that finally are ashen in the centre with a dark reddish brown border (Fig. 1). Such spots may occur in any location on the leaf and are not limited to the radiating vascular bundles.