Final diagnosis


Thanatephorus cucumeris, Rhizoctonia solani (Damping off)

On this salad, a wet, blackish rot is well in place on several basal leaves, some of them wither and gradually decompose. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "bottom rot")
The leaves of this salad show a rather dry brown rot located near the midrib. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, basal rot, bottom rot)
Salad stalk colonized by <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, basal rot, bottom rot)
<b><i>Thanatephorus cucumeris</i></b> (<i>Rhizoctonia solani</i>, ) basal rot, bottom rot).
Numerous basal leaves show moist, brown lesions located on either side of the midrib; in some of them the midrib is starting to rot. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, basal rot, bottom rot)
In the presence of moisture and secondary bacteria, the rot is more humid and dark brown to black in color. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "damping-off", "bottom rot")
Lettuce leaf attacked by <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, basal rot, bottom rot)
Basal rot on salad : <b><i>Thanatephorus cucumeris</i></b> (<i>Rhizoctonia solani</i>, bottom rot)
Several ribs of this lettuce are dotted with or even covered with numerous small, elongated rust-brown lesions. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "bottom rot")
Chancery, concave, dark brown alterations are sometimes observed on certain veins. We can also notice a discreet mycelial pattern. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "bottom rot")
The young leaves of the heart, particularly sensitive, literally melt under the effects of this wet and black rot. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "damping-off", "bottom rot")
On this type of salad, it is first the fragile and not very extended blade that is altered, the main vein apparently remaining intact. The diseased tissue initially takes on a beige tint. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "damping-off", "bottom rot")
This young plant attacked early by <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "damping-off") did not die prematurely. It has a fairly reduced root system; many roots and rootlets did not form or disappeared after turning brown and necrosis.
Careful observation of healthy tissue near diseased tissue reveals the characteristic brown mycelium of <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, " damping-off "," bottom rot ")
On tissues colonized by <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "damping-off", "bottom rot"), we sometimes observe, at the Using a binocular magnifying glass, the brown, septate mycelium characteristic of this fungus.
Mycelial filaments running along the surface of the leaf blade of a salad leaf. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, basal rot, bottom rot)
<b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "damping-off", "bottom rot") is characterized by a brown, septate, constricted mycelium at the base of the ramifications.
The mycelium of <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "damping-off", "bottom rot") is characterized by its robust appearance, between 5 and 15 µm and a dark brown color. There is also a slight constriction at the side ramifications as well as the presence of partitions.
Keg-shaped articles can be seen on the mycelium; they are considered to be blank sclerotia. <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, "damping-off", "bottom rot")
<b><i>Thanatephorus cucumeris</i></b> (<i>Rhizoctonia solani</i>, bottom rot)
These poorly defined masses progressively browning along the midrib are pseudosclerotia of <b> <i> Thanatephorus cucumeris </i> </b> (<i> Rhizoctonia solani </i>, basal rot, bottom rot)