Context:
New study discovers 62 desiccation-tolerant (DT) vascular plant species in Western Ghats, with potential applications in agriculture & conservation.
About DT Plant:
- Most common residents of tropical rock outcrops.
- Can withstand extreme dehydration, losing up to 95 per cent of their water content.
- Can recover quickly when water supplies are restored.
- Can be used to create a high-temperature tolerant variety of crops.
- Can thrive in harsh environments and are termed as extremophytes.
- Found in both flowering and non-flowering species and in both temperate and tropical climates.
Extremophytes are found in extreme habitats, like hot and cold deserts, estuaries, rock outcrops, glaciers and other arid and semi-arid regions. These plant species develop adaptive strategies to survive through morphological and physiological traits.
Findings of the Study:
- Western Ghats – Designated as a global desiccation tolerant hotspot
- 2 strategies for plants in extreme habitats – Hydration and desiccation-tolerance
- Preferred habitats – Ferricretes (layers of sedimentary rock) and basaltic plateaus
Hydration is a condition where plant tissues can tolerate more than 30% of water content whereas in desiccation, plants undergo longer dry days during which the moisture content of the leaves is the same as in the air.
| Species | Response to Dry Conditions |
| Tripogon | Changes its colors from greyish in dry conditions to green in hydrated situations.Turning orange to brownish yellow in the beginning of greening |
| Oropetium Thomaeum | Changes color from green in hydrated phase to dark purple or orange during the period of desiccation. |
| Ferns (Fronds) | Curling inwards towards the costaExposing spores at the start of the dry season and during brief dry spells. |
| C lanuginosus | Does not directly expose leaves to sunlight during the desiccation phase. |
Source: Down to Earth
Which of the following leaf modifications occur (s) in the desert areas to inhibit water loss?
- Hard and waxy leaves
- Tiny leaves
- Thorns instead of leaves
Select the correct answer using the code given below:
[UPSC Civil Services Exam – 2018 Prelims]
- 2 and 3 only
- 2 only
- 3 only
- 1, 2 and 3
