UPSC Prelims 2025 Q39: Plant Growth Forms – Cassava to Papaya
Consider the following pairs:
(Plant : Description)
I. Cassava : Woody shrub
II. Ginger : Herb with pseudostem
III. Malabar spinach : Herbaceous climber
IV. Mint : Annual shrub
V. Papaya : Woody shrub
How many of the above pairs are correctly matched?
- Only two
- Only three
- Only four
- All the five
Answer: (b) Only three
Statement-wise explanation
- I: correct — Cassava (Manihot esculenta) is a woody perennial shrub, usually 1–3 m tall, with a lignified stem. Farmers grow it from woody stem cuttings. Its starchy tuberous roots are the source of tapioca and sago.
- II: correct — Ginger (Zingiber officinale) is a perennial herb. Its true stem is the underground rhizome. The upright 'stem' above ground is a pseudostem made of rolled, overlapping leaf sheaths, the same structure seen in banana.
- III: correct — Malabar spinach (Basella alba) is a fast-growing, soft-stemmed twining vine. It has fleshy leaves and stems and is a tropical perennial that is often grown as an annual. A non-woody plant that climbs is a herbaceous climber.
- IV: incorrect — Mint (Mentha) is a perennial herb, not an annual shrub. It has soft, square stems that do not turn woody, and it spreads by runners and rhizomes, so one planting lasts for years. Both words in the description are wrong.
- V: incorrect — Papaya (Carica papaya) looks like a tree, but its stem is soft and hollow and makes very little true wood. Botanists call it a giant herb, or a tree-like herbaceous plant. It is also unbranched, while a shrub is a low plant with many branching woody stems.
How to eliminate
Basic knowledge settles most of this question. Mint is the easiest pair: anyone who has grown it knows it is a soft herb that keeps coming back, so 'annual shrub' is wrong. That rules out the option claiming all five pairs are correct. Ginger with a pseudostem is a standard textbook example, and a vine grown as a leafy vegetable is plainly a herbaceous climber, so II and III look safe. That leaves cassava and papaya. They are listed with the same description, so ask which one actually has a woody stem. Cassava is grown from hard stem cuttings. Papaya's trunk is soft, spongy and hollow. If you put cassava as woody and papaya as non-woody, the count comes to three. Fact to remember: papaya is a 'giant herb' with no true wood.
Know more
Plant growth forms describe a plant by how much wood it makes, how long it lives, and how it grows.
- Herb: has a soft, green, non-woody stem. It may be annual (e.g. wheat), biennial or perennial (e.g. mint, ginger).
- Shrub: woody and many-stemmed, usually under about 5 m (e.g. cassava, hibiscus).
- Tree: woody with one main trunk that thickens through secondary growth (e.g. mango).
- Climber: a weak stem that needs support. It may be herbaceous (Malabar spinach, gourds) or woody (a liana, e.g. bougainvillea).
Look-alikes UPSC likes to test
| Plant | Looks like | Actually |
|---|---|---|
| Banana | Tree | Giant herb; pseudostem of leaf sheaths |
| Papaya | Tree | Giant herb; soft, hollow stem |
| Ginger, turmeric | Leafy stem | Herb; true stem is the underground rhizome |
| Bamboo | Tree | Woody grass |
| Cassava | Herb (tuber crop) | Woody shrub |
Modified stems and roots. Ginger and turmeric store food in rhizomes, which are underground stems. Potato stores food in a stem tuber. Cassava and sweet potato store it in tuberous roots. A pseudostem is not a stem at all. It is made of leaf sheaths, as in ginger, banana and cardamom.
Origin. Cassava and papaya are both New World crops that reached India from tropical America. In India, cassava (tapioca) is grown mainly in Kerala and Tamil Nadu. Tamil Nadu's Salem region processes it into sago.
NCERT Concepts to Revise
- New World crops: Two plants in this question, cassava and papaya, came to India from the Americas. This helps you place them among introduced crops.
- Horticulture: All five plants are horticulture crops (tuber crop, spice, vegetable, herb, fruit), which is how Indian crop statistics group them.