Drechslera

Drechslera is a genus of filamentous fungi in the family Pleosporaceae, order Pleosporales. Species within this genus are cosmopolitan in distribution, occurring in temperate and tropical regions worldwide. They are typically saprophytic on dead plant material but can act as opportunistic pathogens on living hosts. The generic name derives from the German mycologist Franz Wilhelm von Drechsler, who contributed extensively to fungal taxonomy.

Morphologically, Drechslera species produce conidiophores that are usually determined by the arrangement of their conidia, which are flat, lanceolate to oblong or ellipsoidal, often bearing a septum at the basal end. The conidia stain pinkish or brownish with 0.5 % lactic acid, aiding microscopic identification. The fruiting bodies are macroconidia and microconidia can appear in chains or singly. Sporulation typically occurs on necrotic tissue or decomposing plant residues.

Drechslera species are known plant pathogens that affect a wide range of crops, including cereals such as wheat, barley, oats, and rye, as well as forage grasses and ornamental plants. Common disease symptoms include leaf spots, blights, and stem cankers, often exacerbated by favorable moisture and temperature conditions. In particular, Drechslera zeae is a notable pathogen of corn that can reduce yield and grain quality.

Control strategies rely on cultural practices such as crop rotation, removal of infected residues, and resistant cultivars. Fungicide applications are employed when disease pressure is high, though resistance development is a concern. Biological control agents, including antagonistic bacteria and other fungi, are under investigation as sustainable alternatives. The genus continues to be studied for its ecological role and impact on agriculture worldwide.