Diseases

Leaf spots of timothy grass

Phleum pratense L.

A complex of fungal diseases caused by the species Cladosporium phlei, Drechslera phlei, and Mastigosporium kitzebergense, which reduce the crop's seed yield by 20–30%. The diseases are characterized by the formation of specific necrotic spots and streaks on the leaf blades.

In the reference 12 varieties crop Timothy grass, where this is mentioned in the description.

Heterosporiosis, caused by Cladosporium phlei, is a disease specific to timothy grass, manifesting as small light-brown spots 2–3 mm in size with a purple border. The disease development peaks at 72% during the seed ripening phase under conditions of high humidity and moderate temperatures.

Brown leaf spot, caused by Drechslera phlei, is accompanied by the appearance of elongated necrotic spots and streaks with a chlorotic halo, the edges of which have a dark purple or chocolate-brown hue. The merging of lesion sites leads to massive necrosis of leaf tissue.

Mastigosporiosis on this crop manifests with the involvement of the highly specialized species Mastigosporium kitzebergense. Breeding for resistance to this disease complex is currently based primarily on the phenotypic selection of less susceptible forms due to the lack of data on resistance genes.

General information about the subject — on the page Leaf spot diseases.

Sources7

Varieties of Timothy grass mentioned in the description

Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.