First report of Fusarium poae associated with and/or causing silvertop on loloid-type Festulolium in the Czech Republic

Abstract

Silvertop is a serious disease of grasses, and severe infestations cause a great deal of damage every year (particularly to seed producers). Inflorescences of infected plants dry prematurely and are sterile. The genera Festuca, Poa, Agrostis, Trisetum, and Cynosurus are the most frequent hosts of this disease, which has newly been reported in a loloid-type intergeneric Festulolium hybrid. The disease was also observed in the genus Lolium, with only rare previous description. The suspicion that Fusarium poae is the causal agent of severe silvertop was confirmed, and the pathogen was morphologically described and confirmed by molecular analysis. The meadow plant bug (Leptopterna dolabrata) may be a vector transferring the pathogen to plants, although a direct pathogen transfer was not demonstrated. Grass colonisation by the pathogen therefore apparently occurs after plant tissues injury by sucking of the meadow plant bug.