Disease

Symptoms: This disease appears as a white powder coating over the leaf surface. This disease leads to foliage dryness. 
Advice: Irrigation by spraying can reduce the severity of the attack.

Symptoms: Present primarily in open-field crops, Nasonovia r. develops in early spring.
Advices: use resistant varieties.

Symptoms: It attacks a number of host plants, including lettuce, by damping off and especially rotting off the base leaves as the plant approaches maturity.
Advice: Foliar treatments with approved fungicides (11-13 leaf stage maximum) and good aeration of the crop (especially sheltered).

Symptoms: They appear in the form of white carpophores which appear primarily on the lower surface of the leaves and cotyledons and light green to yellow spots with a somewhat angular shape.
Advices: Downy mildew is controlled through the use of resistant varieties and approved fungicides during growing cycle, but also by ensuring the production of healthy, unstressed plants from the moment they emerge.

Symptom: Stringy and rigid leaflets (not to be confused with hormone damage), puckered and checkered leaflets, blistered fruit with yellow rings or swirls, stunted plants in the case of early attacks.
Advice: Remove weeds (which are reservoirs for viruses) around the plants. Create a trap crop around the field. Eliminate aphids, destroy suspicious plants,
protect young plants in a nursery and regularly clean all tools.

Symptoms: Small greasy spots surrounded by a yellow-colored halo on the leaf. Growing spots cause leaf and petiole necrosis.
Advice: Use healthy seeds and apply copper-based treatment product to the foliage.