Lettuce powdery mildew (Erysiphe cichoracearum) – identify and control

Lettuce powdery mildew, Erysiphe cichoracearum was first discovered in the USA in 1931. It is favored by warm, dry conditions and occurs primarily on mature lettuce.

Symptoms. The powdery mildew on lettuce manifests on the upper face of the leaves, as a gray-white, powdery growth. The leaves turn yellow, lose their color, and wilt. Sometimes the small, brown spherical structures of the pathogen (cleistothecia) may be seen on the leaves.

The pathogen agent is Erysiphe cichoracearum. The fungus attacks the lettuce in conditions of high humidity 77-85%, low light, and temperatures of 10-32°C. The fungus is spread by spores. The transmission from one year to another takes place through the cleistothecium (resistance fructifications) left on the vegetal debris.

Prevention and control. To prevent the appearance of the fungus, it is recommended to apply a normal watering regime, ensure aeration of the crop, as well as cultivate healthy seeds. To control the disease during the growing season, treatments with specific fungicides are applied.

Recommended products

Read carefully and follow the instructions on the label of each product
×

We help you
to take care of your plants

If you haven't yet found solutions in our articles or previous discussions, start a new discussion and our experts will help you.

New discussion about

Lettuce powdery mildew (Erysiphe cichoracearum) – identify and control
Lettuce powdery mildew (Erysiphe cichoracearum) – identify and control

Your information:

Your name must contain a maximum of 30 characters. If you would like to pass on the details of the problem you are facing, please complete the other fields.

The maximum document size is 59 MB.

Add
It helps if you attach some Images or Clips maximumm 15 sec