Texas FFA Nursery Landscape Practice Exam

What causes damping-off in plants?

1. Fungi

2. Viruses

3. Bacteria

4. Nematodes

The correct answer is: Fungi

Damping-off is a common issue in plant health, particularly affecting seedlings and young plants, and it is primarily caused by fungi. This condition leads to the rotting of stems and roots, which can result in the collapse and death of the plants. The fungal pathogens responsible for damping-off thrive in overly moist conditions and can easily spread through contaminated soil, water, tools, or plant debris. The fungi involved often belong to genera such as Pythium, Rhizoctonia, and Fusarium. These pathogens can infect plants at various stages of growth, but they are particularly harmful during the germination phase when the seedlings are most vulnerable. Recognizing fungi as the primary cause of damping-off is crucial for implementing prevention strategies, such as improving drainage, avoiding over-watering, using sterilized growing media, and practicing crop rotation to reduce the fungal load in the soil. While viruses, bacteria, and nematodes can all cause issues for plants, they are not the primary agents responsible for damping-off. Viruses typically cause systemic symptoms and do not lead to the characteristic stem and root rot associated with damping-off. Bacteria may lead to soft rot or other types of decay, but again, do not present the same symptoms as damping-off. N