Prelims 2013 · Environment · Question 47
Mycorrhizal biotechnology has been used in rehabilitating degraded sites because mycorrhiza enables the plants to<br/>1. Resist drought and increase absorptive area<br/>2. Tolerate extremes of pH<br/>3. Resist disease infestation<br/><br/>Select the correct answer using the codes given below:
Answer
1, 2 and 3
1. Resist drought and increase absorptive area — Correct. Mycorrhiza is a symbiotic association of fungi with roots; fungal hyphae greatly increase the effective absorptive surface and improve water uptake, helping plants withstand drought.
2. Tolerate extremes of pH — Correct. Mycorrhiza helps plants survive in degraded soils by improving nutrient uptake and buffering stress in adverse soil conditions, including acidic or alkaline pH.
3. Resist disease infestation — Correct. Mycorrhizal association can protect roots against several soil-borne pathogens and enhance overall plant resistance.
Hence, all three statements are correct.