Question

Vesicular arbuscular mycorrhizae (VAM) are important in
(a) Nitrate uptake
(b) Phosphate uptake
(c) Both A and B
(d) Sulfate uptake

Answer 1

Hint: Vesicular arbuscular mycorrhizae help plants in uptake of those nutrients from the soil that are necessary for the plants in the growth of leaves and good green color and also for the formation of new roots, fruiting, and flowering.

Complete answer:
As VAM is a type of mycorrhiza, it is a similar symbiotic association between green plants and fungus where the fungal component belongs to Phycomycetes while the plant is generally angiosperm. In this association, the fungus assists the host plant in the uptake of nitrogen and phosphorus that are vital to the plant growth because the former nutrient helps in the growth of leaves and maintenance of green color while the latter one is important for root and shoot growth, fruiting, and flowering. An increase in nutrient uptake is achieved in this association because due to the presence of a fungal partner, the net surface area of the host plant is increased several times. When the fungus colonizes the root cortex of the plant, it forms two types of structures – the first one is a mycelial network and the second one is arbuscular. The vesicles are bladder-like structures while the arbuscules are branched fingers like hyphae. These two structures help in increasing the surface area for nutrient uptake.
So, the correct answer is “(c) Both (a) and (b)”.

Note: The name of this type of mycorrhiza is Vesicular arbuscular mycorrhizae (VAM) that have been given due to the formation of branched hyphae by the fungal partner. These branched finger-like hyphae are known as arbuscules.