Cucumber Mosaic
Agent: Cucumis virus
Symptoms
Transmitted by aphids, does not survive winter in soil or plants. The first symptom is leaves with raised stripe-shaped spots, which later appear on the stem and fruits.
Control and prevention
It's difficult to cure — the plant must be destroyed. Combat aphids (vectors), disinfect tools. There are no resistant varieties yet.
Related problems
Similar symptoms might indicate a different cause — compare them.
Bacterial spot
Manifests as dark spots with a raised center on leaves and stems, later the leaves begin to yellow. Dark, growing spots may appear on the fruits. Cool, humid weather and splashing water droplets allow the disease to spread rapidly.
Early blight and black fruit rot
Alternaria solani
Usually appears when fruits begin to set. First affects the lower leaves, then the stem and fruits. Large brown or black spots with concentric rings appear on them. Around the spot, the leaf begins to yellow and dies. It also attacks potatoes and eggplants. The fungus is resistant and persists for several years.
Mold
Symptoms caused by various fungi. Mold only survives in high humidity.