Septoria tritici is the causal agent of S. tritici leaf blotch, a foliar disease of wheat

Wheat

Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...

, and occasionally infects other grasses including barley

Barley

Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods...

. It is found in all wheat growing areas of the world
and is the major disease of wheat in the UK.

The teleomorph is Mycosphaerella graminicola

Mycosphaerella graminicola

Mycosphaerella graminicola is a wheat plant pathogen that is difficult to control due to resistance to multiple fungicides.-External links:* *...

(Fuckel) Schröter

Morphology

Asexual state: Pycnidiospores are hyaline and threadlike and measure 1.7-3.4 x 39-86 μm, with 3 to 7 indistinct septations. Germiniation of pycnidiospores can be lateral or terminal. Cirrhi are milky white to buff. Sometimes in culture nonseptate, hyaline microspores, measuring 1-1.3 x 5-9 μm, occur outside pycnidia by yeastlike budding.

Sexual state: Perithecia are subepidermal, globose, dark brown, and 68-114 μm in diameter. Asci measure 11-14 x 30-40 μm. Ascospores are hyaline, elliptical, and 2.5-4 x 9-16 μm, with two cells of unequal length.

Epidemiology

The period between infection and formation of sporulating structures (latent period) was estimated to be 20.35 ± 4.15 days for S. tritici and decreased with increasing temperature.

External references

• Septoria Tritici Blotch, Kansas State University