The four major groups of plant pathogens include fungi, bacteria, virus and ____________.

The four major groups of plant pathogens include fungi, bacteria, virus and ____________.

• A. Nematodes
• B. Aphids
• C. Moss
• D. Blights

Answer: (A)

Nematodes are a major group of plant pathogens alongside fungi, bacteria, and viruses. These are microscopic, soil-dwelling roundworms that parasitize roots and other plant tissues, feeding on cells and disrupting water and nutrient uptake. The resulting damage stunts growth, causes yellowing, and can lead to yield losses. Aphids are insects and can transmit diseases but aren’t classified as a primary pathogen group; moss is a non-pathogenic plant category, not a pathogen group; blights describe disease symptoms or outbreaks rather than a separate pathogen category. So the missing term is nematodes.

Nematodes are a major group of plant pathogens alongside fungi, bacteria, and viruses. These are microscopic, soil-dwelling roundworms that parasitize roots and other plant tissues, feeding on cells and disrupting water and nutrient uptake. The resulting damage stunts growth, causes yellowing, and can lead to yield losses. Aphids are insects and can transmit diseases but aren’t classified as a primary pathogen group; moss is a non-pathogenic plant category, not a pathogen group; blights describe disease symptoms or outbreaks rather than a separate pathogen category. So the missing term is nematodes.