Mycorrhizal biotechnology has been used in rehabilitating degraded sites because mycorrhiza enables the plants to
- 1.Resist drought and increase absorptive area
- 2.Tolerate extremes of pH
- 3.Resist disease infestation
Select the correct answer using the codes given below:
Answer & explanation
Answer: (d) 1, 2 and 3
Mycorrhiza refers to a mutually beneficial partnership in which fungi live in association with the roots of higher plants. The fungal hyphae extend the root's absorbing surface and help the plant take up water and nutrients. The association also makes plants more tolerant of drought and of adverse soil conditions such as low pH, and more resistant to root-borne pathogens. All three statements are correct, which is why mycorrhizal inoculation is used to revegetate degraded sites.
- ✓ 1. Plants with mycorrhizal associations show tolerance to drought. The fungus helps the plant absorb essential nutrients from the soil, and its hyphae add to the absorbing surface of the root system.
- ✓ 2. Arbuscular mycorrhizal fungi help host plants resist stresses such as low soil pH, toxic elements and extreme temperatures. This is why they are used to rehabilitate disturbed land, such as mine spoils.
- ✓ 3. Resistance to root-borne pathogens is one of the benefits plants gain from mycorrhizal association.
Remember · Mycorrhiza (a fungus–root symbiosis, e.g. Glomus) improves phosphorus and water uptake. It also gives tolerance to drought, salinity and pH stress, and resistance to root pathogens, which makes it useful for restoring degraded land.
📘 Read it in NCERT: Class 12 Biology, Ch 8 (practise this chapter) · Class 12 Biology, Ch 11 (practise this chapter)
Sources
- NCERT Class 12 · Biology, Chapter 8 “Plants having such associations show other benefits also, such as resistance to root-borne pathogens, tolerance to salinity and drought, and an overall increase in plant growth and development.”
- NCERT Class 12 · Biology, Chapter 11 “the mycorrhizae are associations between fungi and the roots of higher plants. The fungi help the plant in the absorption of essential nutrients from the soil”
- Review: Arbuscular mycorrhizal fungi in rehabilitation of disturbed land (PMC10489935, US National Library of Medicine) ↗ “The expansion of AMF has a dietary benefit to related plants, supplying viable resistance from lower pH, weighty foil toxicants, and excessive temperature”
Question: UPSC Civil Services (Preliminary) 2013, General Studies Paper I. Explanation: Minimalist IAS, checked 25 Oct 2026 (how we verify). ·
