Which of the following is NOT a biotic pathogen?

Which of the following is NOT a biotic pathogen?

• A. Fungal rusts
• B. Nutrient deficiencies
• C. Nematodes
• D. Viruses

Answer: (B)

Biotic pathogens are living agents that infect plants and cause disease. Fungal rusts, nematodes, and viruses fit this, because they are organisms that invade tissues and reproduce. Nutrient deficiencies, by contrast, are abiotic stresses caused by a lack or imbalance of essential nutrients in the soil; they don’t involve an invading organism, so they aren’t biotic pathogens. Recognizing this distinction helps guide management toward nutrient management and soil health rather than pathogen-focused controls.

Biotic pathogens are living agents that infect plants and cause disease. Fungal rusts, nematodes, and viruses fit this, because they are organisms that invade tissues and reproduce. Nutrient deficiencies, by contrast, are abiotic stresses caused by a lack or imbalance of essential nutrients in the soil; they don’t involve an invading organism, so they aren’t biotic pathogens. Recognizing this distinction helps guide management toward nutrient management and soil health rather than pathogen-focused controls.