Which one of the following is not a biofertilizer ?
- Agrobacterium
- Nostoc
- Rhizobium
- Mycorrhiza
Answer
(1) Agrobacterium
Solution
As per NCERT, the main sources of biofertilisers are bacteria, fungi and cyanobacteria:
Rhizobium ⇒ symbiotic nitrogen fixer in root nodules of legumes
Nostoc ⇒ free-living nitrogen-fixing cyanobacterium
Mycorrhiza ⇒ fungus (e.g., Glomus) that absorbs phosphorus for the plant
Agrobacterium ⇒ a plant pathogen (crown gall), used as a vector in genetic engineering, not a biofertiliser.
Answer: (1)