''Zymoseptoria tritici'', synonyms ''Septoria tritici'', ''Mycosphaerella graminicola'', is a species of filamentous fungus, an ascomycete in the family ''

Mycosphaerellaceae The Mycosphaerellaceae are a family of sac fungi. They affect many common plants, such as eucalyptus, the myrtle family, and the Proteaceae The Proteaceae form a family of flowering plants predominantly distributed in the Southern Hemisph ...

''. It is a

wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...

plant pathogen causing septoria leaf blotch that is difficult to control due to resistance to multiple fungicides. The pathogen today causes one of the most important diseases of wheat. In 2011, Quaedvlieg et al. introduced a

new combination ''Combinatio nova'', abbreviated ''comb. nov.'' (sometimes ''n. comb.''), is Latin for "new combination". It is used in taxonomic biology literature when a new name is introduced based on a pre-existing name. The term should not to be confused wi ...

for this species: ''Zymoseptoria tritici'' (Desm.) Quaedvlieg & Crous, 2011, as they found that the type strains of both the genus ''Mycosphaerella'' (linked to the anamorph genus ''Ramularia'') and the genus ''Septoria'' (linked to the genus ''Septoria'', an extensive clade of very distinct septoria-like species within the ''Mycosphaerellaceae'') clustered separately from the clade containing both ''Zymoseptoria tritici'' and ''Z. passerinii''. Since 2011, a total of eight ''Zymoseptoria'' species have been described within the genus ''Zymoseptoria''; ''Z. tritici'' (the type of the genus ''Zymoseptoria''), ''Z. pseudotritici, Z. ardabiliae, Z. brevis, Z. passerinii, Z. halophila, Z. crescenta'' and ''Z. verkleyi'' (Named after Gerard J.M. Verkleij, for the contribution that he has made to further the understanding of the genus ''Septoria'').

Description

This fungus causes septoria tritici blotch of wheat, a disease characterized by necrotic blotches on the foliage. These blotches contain asexual (

pycnidia A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales ( Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inverse ...

) and sexual (

pseudothecia An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are mos ...

) fructifications. Asexual state ( anamorph, asexual stage was previously named as ''Septoria tritici''):

Pycnidiospore {{Short pages monitor