Final diagnosis


Mycocentrospora acerina (Mycocentrospora leaf spot)

Several translucent to brown spots are visible on this lettuce leaf. A number of them are starting to split. Ultimately, they will give way to perforations. <b> <i> Mycocentrospora acerina </i> </b> ("<i> mycocentrospora </i> leaf spot")
Reddish-brown alterations are also visible on the midrib. <b> <i> Mycocentrospora acerina </i> </b> ("<i> mycocentrospora </i> leaf spot")
Appearance of the conidia of <i> <b> Mycocentrospora acerina </b> </i> ("mycocentrospora leaf spot"): scraping the damaged tissues makes it possible to recover the conidia characteristic of this fungus. They are pluri-septate, hyaline, long stretched and have a thin and tapering lateral appendage.
In addition to multicellular conidia, <b> <i> Mycocentrospora acerina </i> </b> ("<i> mycocentrospora </i> leaf spot") produces clusters of swollen and brown cells (17-30 µm) ("chlamydospores") which contribute to its conservation.