Podosphaera macularis

Powdery mildew Podosphaera macularis

Description

Podosphaera macularis is a fungal pathogen that causes powdery mildew on Humulus ssp., particularly hops (Humulus lupulus). It primarily affects the leaves, stems, and cones of the plant, forming white, powdery fungal growth. This disease can reduce photosynthesis, stunt plant growth, and impact the quality and yield of hop cones. The fungus thrives in moderate temperatures and high humidity but does not require free water to spread, making it a significant issue in hop-growing regions. Control methods include the use of resistant cultivars, fungicides, and proper spacing for airflow.

Symptom

Symptoms of Podosphaera macularis on hops include white, powdery fungal growth on the upper surfaces of leaves, stems, and hop cones, leading to leaf distortion and reduced cone quality. Infected plants may show stunted growth and premature leaf drop.

Tree Species: Hop

Part of a plant- attacked: Leaf / Needle, Fruit / Seed, Branch

Pest significance: Harmful

Pest Category: Fungi

Invasive Species: No

Present in EU: Yes