Sooty mold

• Symptoms  :
  • progressive appearance of one to several molds on the aerial organs of the eggplant which present variable colors, but often blackish.
  • this sooty mold is harmful because it more or less disrupts the photosynthesis of plants and therefore their development, but it sometimes makes their fruits unmarketable.

• Cause(s)  :

  • several insects, including aphids, whiteflies, mealybugs, etc. which during their parasitism take large quantities of sap in order to satisfy their food needs, and in particular in proteins. This forces them to release large amounts of excess sugar in the form of honeydew. This then contaminates the surface of the organs colonized by these insects;

  • this sweet honeydew is a real boon for several phylloplan fungi of many plants and vegetables which use them for food, and which are the source of sooty mold. Their development on this sweet substrate leads to the gradual appearance of one to several molds on the blade (figure 1), the stem (figure 2) and even the fruits (figure 2) which present variable colors depending on the fungal species. colonizers: Alternaria spp., Cladosporium spp., Capnodium sp., Penicillium sp., etc.

• Diagnostic clues :
  • in the presence of sooty mold, observe the plants more closely to detect which insect pests them, then consult its specific sheet: whiteflies, aphids, mealybugs, etc.

• Possible confusion :

• Remedies :
  • only controlling pest populations can remedy this.