Which statement about powdery mildew is false?

Which statement about powdery mildew is false?

• A. There is only one species of powdery mildew that infects all plants.
• B. Powdery mildew can be reduced by improving airflow and reducing shade.
• C. Powdery mildew absorbs nutrients from the leaf, weakening the plants.
• D. For some types of plants, varieties resistant to powdery mildew are available.

Answer: (A)

Powdery mildew is caused by a group of fungal pathogens, not a single species. Different species in genera such as Erysiphe, Sphaerotheca, and Podosphaera infect many different kinds of plants, with each species typically affecting specific hosts. So the idea that there’s only one species that infects all plants is not correct. Cultural practices that improve airflow and reduce shade help because powdery mildew thrives in still, humid microclimates around leaves. More air movement and less dense shading lower leaf humidity and disrupt the conditions that allow the mildew to spread and establish, making infection less likely. The fungus lives on leaf tissue and draws nutrients from the plant, which reduces photosynthesis and weakens the plant overall. That nutrient drain is part of why infected plants often look stressed or grow more slowly. Resistance exists for some plants, with certain varieties bred to withstand powdery mildew. When such resistant cultivars are available, they can be an effective and durable part of disease management.

Powdery mildew is caused by a group of fungal pathogens, not a single species. Different species in genera such as Erysiphe, Sphaerotheca, and Podosphaera infect many different kinds of plants, with each species typically affecting specific hosts. So the idea that there’s only one species that infects all plants is not correct.

Cultural practices that improve airflow and reduce shade help because powdery mildew thrives in still, humid microclimates around leaves. More air movement and less dense shading lower leaf humidity and disrupt the conditions that allow the mildew to spread and establish, making infection less likely.

The fungus lives on leaf tissue and draws nutrients from the plant, which reduces photosynthesis and weakens the plant overall. That nutrient drain is part of why infected plants often look stressed or grow more slowly.

Resistance exists for some plants, with certain varieties bred to withstand powdery mildew. When such resistant cultivars are available, they can be an effective and durable part of disease management.