Question

Which one of the following can be used as a biofertilizer?
a. Plasmodium
b. Rhizobium
c. Chenopodium
d. Agrobacterium

Answer 1

Hint: The microorganisms which, when applied to seed, plant surfaces, or soil, colonizes the interior of the plant is called Biofertilizers. Biofertilizers also promote growth by increasing the supply or availability of primary nutrients to the host plant Biofertilizer is the organically vigorous products that help in the growth and providing nutrients to the plants.

Complete answer:
> Rhizobium is a bacterium (sing. Of bacteria) that can convert atmospheric nitrogen into the consumable form. The consumed form of N can be used by the plants. It cannot make its food. So, it shows a symbiotic relationship and lives in the root of some legumes and provides them with nitrogen. In return, food and shelter are provided by plants to the bacterium. So, it acts as a fertilizer. Thus, option B is correct.

> Plasmodium is a eukaryotic organism belonging to the Sub-Kingdom Protozoa of Animal Kingdom. It belongs to the group Sporozoa (Protozoans without locomotory organs) of Protozoa and mainly causes malaria in humans and can infect various Animals.

> Chenopodium is the annual plant and erect that grows 150cm tall. It belongs to the family Amaranthaceae. Chenopodium is a weed. So option C is wrong

> Agrobacterium is one of the common species and gram-negative. It caused tumors in plants. Agrobacterium is a soil-borne bacteria and is used as a natural vector. So, option D is wrong

Hence, the correct answer is option (B).

Note: Rhizobium is helpful to farmers as these bacteria can reduce the use of nitrogenous fertilizers where leguminous plants are grown. It makes root nodules and thus can be called root node bacteria. It is an aerobic bacteria showing a symbiotic relationship with legumes.