Choose the incorrect statement –

Correct option is B

The correct answer is (B) Some plant parasites known as obligate parasite complete their life cycle without a host

Explanation:
• An obligate parasite is an organism that cannot complete its life cycle without exploiting a suitable host. This is the defining characteristic of being 'obligate'.
• If an obligate parasite is unable to find a host, it will fail to grow and reproduce.
• Common examples of obligate parasites include viruses, some bacteria, and fungi like rusts and powdery mildews.
• In contrast, 'facultative' organisms can live either as parasites or saprophytes depending on the environmental conditions.
• Therefore, statement B is factually incorrect.

Information Booster:
• Plant pathology (Phytopathology) is the study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors).

Additional Knowledge:
• Plant pathogens (Option A): These include fungi, bacteria, viruses, nematodes, and protozoa that cause biotic (infectious) diseases.
• Saprophytes (Option C): These are essential for the ecosystem as they break down dead organic matter (detritus), recycling nutrients back into the soil.
• Fungi (Option D): Most fungi are composed of hyphae, which collectively form a mycelium. They are heterotrophic and absorb nutrients through their cell walls.