Final diagnosis


Myrothecium lesions (M. roridum)

Melon
Several incipient spots caused by <i>Myrothecium roridum</i> are clearly visible on this melon leaf.
Many spots dot this melon leaf. They are brown, of variable shapes, and show concentric patterns. The limbus at the periphery of the lesions is chlorotic. <i>Myrothecium roridum</i>
Appearance of lesions observed on the lower face of the limbus. Some are greasy and/or located on the ribs. <i>Myrothecium roridum</i> are clearly visible on these weathered melon leaf tissues.
The spots gradually necroticized and dried out on this melon leaf. The altered tissues have decomposed and fallen off, giving the blade a holey appearance. <i>Myrothecium roridum</i>
Some spots have converged on this melon leaf. The altered tissues are decomposed, necrotic and more or less dried out. <i><b>Myrothecium roridum</b></i>
Detail of well evolved lesions: the decomposed central tissues split, disintegrate and fall. Note that the leaf blade of this melon leaf is rather chlorotic. (<i>Myrothecium roridum</i>)
Sectors of the leaf blade of this particularly degraded melon leaf gradually disintegrate. <i>Myrothecium roridum</i>
Appearance of lesions caused by <i>Myrothecium roridum</i> on pungent cucumber leaf (<i>Cucumis anguria</i>)
Appearance of lesions caused by <i>Myrothecium roridum</i> on bitter cucumber (<i>Momordica charantia</i>) leaf
Appearance of lesions caused by <i>Myrothecium roridum</i> on calabash leaf (<i>Lagenaria siceraria</i>)
Appearance of lesions caused by <i>Myrothecium roridum</i> on calabash leaf (<i>Lagenaria siceraria</i>)
Appearance of lesions caused by <i><b>Myrothecium roridum</i></b> on sorossi leaf (<i>Momordica charantia</i>)
Appearance of <i><b>Myrothecium roridum</b></i> fruiting bodies on altered sorossi (<i>Momordica charantia</i>) leaf.
Appearance of lesions caused by <i>Myrothecium roridum</i> on sponge gourd leaf (<i>Luffa aegyptiaca</i>)
Okra
On these okra leaves, the spots are more developed. The central fabrics have broken down, dried and fallen off. the blade is now perforated. <i><b>Myrothecium</b></i> sp.
Two large, circular, brownish spots cover this tomato leaf. Concentric patterns are clearly visible, as well as a rather diffuse halo. <i><b>Myrothecium roridum</i></b>
Several circular and brownish spots dot this eggplant leaf. Concentric patterns are clearly visible, as well as a rather diffuse halo. <i>Myrothecium roridum</i>
Detail of a lesion on eggplant leaf induced by. <i>Myrothecium roridum</i>. Note the presence of numerous small blackish pads marbling the necrotic tissue. These structures sign the parasitism of this fungus.
Piment-Plante
A circular lesion has formed at the edge of the leaf blade of this pepper leaf. Brown to dark brown in color, it has clearly visible concentric patterns. A halo diffuses the belt. <i>Myrothecium roridum</i>
Detail of a lesion on pepper leaf produced by. <i>Myrothecium roridum</i>. Note the presence of small blackish pads on the underside of the blade, very characteristic structures of this mushroom.
Baselle
Large brownish lesion on the upper side of a basella leaf; it is still moist on the periphery, lighter in its center where discrete concentric patterns are observable. <i>Myrothecium</i> sp.
Appearance of the large brownish lesion observed this time on the underside of a basella leaf; several black sporodochia of the fungus distributed in circles have formed. <i>Myrothecium</i> sp.
Large beigeish lesion on the upper surface of a celery leaf. <i><b>Myrothecium</i> sp.</b>
Cankerous and necrotic lesion on petiole of celery. <i><b>Myrothecium</i> sp.</b>
Microscopie1.jpg
A few greyish to black sporodochia formed on this young leaf lesion. (<i>Myrothecium roridum</i>)
Spodochia may also form on the underside of the lamina. (<i><b>Myrothecium roridum</b></i>)
On this evolved spot on the upper side of the lamina, the sporodochia are more numerous. The conidia en masse constitute the upper, black part of the sporodochia. (<i>Myrothecium roridum</i>)
Appearance of greyish to black sporodochia formed on the lesions, particularly on the leaves. <b><i>Myrothecium roridum</i></b>
Spodochia grouped in a circle are visible on the lesion initiated at the periphery of a celery leaf. The conidia en masse constitute the upper, black part of the sporodochia. (<i><b>Myrothecium roridum</i></b>)
Two sporodochia of <i><b>Myrothecium roridum</b></i> are clearly visible on these altered leaf tissues.
Detail of a sporodochia of <i><b>Myrothecium roridum</b></i>.
Numerous phialides make up part of each sporodochia; they form at their extremity cylindrical conidia, hyaline to slightly olive-coloured. <b><i>Myrothecium roridum</i></b>
Detail of the cylindrical, hyaline to slightly olive-colored conidia of <b><i>Myrothecium roridum</i></b>.