Which one of the following pair is INCORRECTLY matched?

Bacillus thuringiensis is a bacterium used as a bioinsecticide to control insect pests (such as butterfly caterpillars). It is not a mycoherbicide. Mycoherbicides are fungi used to control weeds (e.g., Phytophthora palmivora).

Agrobacterium species are known to act as phosphate solubilizing bacteria (PSB).

Frankia is a symbiotic nitrogen-fixing microbe found in the root nodules of non-leguminous plants like Alnus.

Beijerinckia is a free-living (non-symbiotic) aerobic nitrogen-fixing bacterium.

Therefore, the incorrectly matched pair is Free living mycoherbicide — Bacillus thuringiensis.

Answer: Free living mycoherbicide — Bacillus thuringiensis