Plant: Economic Importance

Q70. Which of the following combinations correctly describes economic botany?

[UPSC CSE — Practice]

1. Study of the physical structure of rocks
2. Study of economically useful plants and their products
3. Study of only wild animals
4. Study of planetary movements

Answer: (B) Study of economically useful plants and their products

Explanation: Economic botany examines plant resources that support food, medicine, fibres, timber, oils and commerce. It links botanical identification with cultivation, harvesting and industrial uses. Because plants form the foundation of many supply chains, the field has important livelihood applications.

Q69. Which plant family includes the principal cereals wheat, rice and maize?

[WBCS — Practice]

1. Poaceae
2. Fabaceae
3. Solanaceae
4. Rutaceae

Answer: (A) Poaceae

Explanation: Wheat, rice and maize are grasses belonging to Poaceae, formerly Gramineae. Their carbohydrate-rich grains are staple foods for billions of people. Most pulses belong instead to Fabaceae, which is noted for protein-rich seeds and nitrogen-fixing symbiosis.

Q68. What is the accepted botanical name of common wheat?

[MPPSC — Practice]

1. Oryza sativa
2. Zea mays
3. Triticum aestivum
4. Cicer arietinum

Answer: (C) Triticum aestivum

Explanation: Triticum aestivum is common bread wheat, a major rabi cereal in India. Oryza sativa denotes Asian rice, Zea mays denotes maize and Cicer arietinum denotes chickpea. Scientific names distinguish crop species irrespective of their regional common names.

Q67. Which is correctly paired with its botanical name?

[UPPCS — Practice]

1. Maize — Oryza sativa
2. Rice — Zea mays
3. Gram — Gossypium herbaceum
4. Rice — Oryza sativa

Answer: (D) Rice — Oryza sativa

Explanation: Asian cultivated rice is Oryza sativa. Maize is Zea mays and gram is Cicer arietinum. Gossypium species are cultivated for cotton fibre, not cereal grains. Accurate plant names are important in seed certification, breeding and crop research.

Q66. Which cereal is particularly adapted to hot, low-rainfall conditions in Rajasthan?

[RAS / RPSC — Practice]

1. Paddy rice
2. Pearl millet (bajra)
3. Oats
4. Water chestnut

Answer: (B) Pearl millet (bajra)

Explanation: Pearl millet tolerates relatively dry and hot conditions and provides food and fodder across semi-arid Rajasthan. Rice generally demands substantially more water. This drought tolerance makes bajra an economically valuable cereal for farming systems exposed to erratic monsoon rainfall.

Q65. Which crop is botanically identified as Zea mays?

[SSC CGL — Practice]

1. Maize
2. Barley
3. Pea
4. Mustard

Answer: (A) Maize

Explanation: Zea mays is maize, an important cereal used as human food, poultry feed, livestock feed and industrial starch. It belongs to the grass family. Other maize-derived products include sweeteners, ethanol and processed foods, illustrating multiple economic uses of one crop.

Q64. Why are pulses particularly important in a cereal-based diet?

[SSC CHSL — Practice]

1. They contain no carbohydrates
2. They supply appreciable vegetable protein
3. They are the main source of timber
4. They always contain vitamin D

Answer: (B) They supply appreciable vegetable protein

Explanation: Pulses such as gram, pigeon pea and lentils provide substantial plant protein. They complement cereal-based diets, which are generally richer in starch. Many pulse crops also improve soil fertility through symbiosis with nitrogen-fixing bacteria in root nodules.

Q63. Which scientific name belongs to chickpea or gram?

[SSC MTS — Practice]

1. Cicer arietinum
2. Cajanus cajan
3. Glycine max
4. Pisum sativum

Answer: (A) Cicer arietinum

Explanation: Cicer arietinum is chickpea, commonly called gram or chana. It is a major pulse consumed as whole grain, split dal and flour. Cajanus cajan is pigeon pea, Glycine max is soybean and Pisum sativum is garden pea.

Q62. Arhar or red gram is obtained from which species?

[RRB NTPC — Practice]

1. Arachis hypogaea
2. Cajanus cajan
3. Triticum aestivum
4. Corchorus capsularis

Answer: (B) Cajanus cajan

Explanation: Cajanus cajan is pigeon pea, also known as arhar or tur. Its protein-rich seeds are used as dal. Unlike cereals, pigeon pea belongs to the legume family and can associate with nitrogen-fixing microorganisms, supporting its role in sustainable cropping systems.

Q61. Which crop is correctly described as a leguminous oilseed?

[RRB Group D — Practice]

1. Groundnut
2. Rice
3. Wheat
4. Jute

Answer: (A) Groundnut

Explanation: Groundnut, Arachis hypogaea, is a leguminous plant whose underground-developing pods contain oil-rich seeds. It provides edible oil, snacks and protein-rich oilcake. Its legume biology distinguishes it from cereals such as rice and wheat and fibre plants such as jute.

Q60. Which botanical name identifies soybean?

[CGPSC — Practice]

1. Glycine max
2. Gossypium arboreum
3. Zingiber officinale
4. Mangifera indica

Answer: (A) Glycine max

Explanation: Glycine max is soybean, valued for both protein and vegetable oil. It supplies food ingredients, animal-feed meal and processed industrial products. Gossypium is cotton, Zingiber officinale is ginger, and Mangifera indica is mango.

Q59. Which pair represents edible oils commonly extracted from plant seeds?

[UPSC CDS — Practice]

1. Castor oil and turpentine
2. Groundnut oil and sesame oil
3. Diesel and kerosene
4. Mineral oil and machine oil

Answer: (B) Groundnut oil and sesame oil

Explanation: Groundnut and sesame seeds yield edible vegetable oils used in food preparation. Castor oil is mainly used in industrial and specialty applications, while turpentine comes from resin-rich trees. Petroleum products such as diesel and kerosene are not edible plant oils.

Q58. Castor oil is chiefly obtained from the seeds of which plant?

[UPSC NDA — Practice]

1. Ricinus communis
2. Cocos nucifera
3. Camellia sinensis
4. Tectona grandis

Answer: (A) Ricinus communis

Explanation: Ricinus communis is the castor plant. Its seeds contain oil used in lubrication, industrial chemicals and selected pharmaceutical preparations after appropriate processing. Raw castor seeds are poisonous because they contain ricin; they must never be treated as edible seeds.

Q57. Which spice is the dried flower bud of a tree?

[WBCS — Practice]

1. Cumin
2. Clove
3. Black pepper
4. Turmeric

Answer: (B) Clove

Explanation: Cloves are the aromatic unopened flower buds of Syzygium aromaticum. They are dried for culinary and commercial use. Cumin comes from fruits, black pepper from dried drupes, and turmeric from underground rhizomes rather than flower buds.

Q56. Which spice is obtained from the rhizome of Curcuma longa?

[RPSC — Practice]

1. Ginger
2. Garlic
3. Turmeric
4. Cinnamon

Answer: (C) Turmeric

Explanation: Curcuma longa produces turmeric rhizomes containing the yellow pigment curcumin. Turmeric is widely used as a spice, colourant and in traditional remedies. Ginger is also a rhizome, but it comes from a different genus, Zingiber.

Q55. Which part of the ginger plant is commonly used as a spice?

[SSC CGL — Practice]

1. Seed coat
2. Rhizome
3. Petal
4. Root hair

Answer: (B) Rhizome

Explanation: The edible and commercial part of ginger is a rhizome, which is an underground modified stem. It stores reserves and bears buds capable of producing new shoots. Ginger is used fresh, dried or processed in foods and beverages.

Q54. What is the botanical source of commercial tea?

[SSC CHSL — Practice]

1. Camellia sinensis
2. Coffea arabica
3. Cinchona officinalis
4. Theobroma cacao

Answer: (A) Camellia sinensis

Explanation: Tea is manufactured mainly from the young leaves and buds of Camellia sinensis. Processing methods produce black, green and other teas. Coffea arabica supplies coffee beans, while Cinchona is associated with quinine and Theobroma cacao with cocoa.

Q53. Coffee as a beverage is prepared mainly from which plant part?

[SSC MTS — Practice]

1. Bark
2. Roasted seeds
3. Leaves
4. Fibrous stem

Answer: (B) Roasted seeds

Explanation: Coffee beans are actually seeds found inside the fruits of Coffea plants. The seeds are processed, roasted and ground to prepare the beverage. Tea, by comparison, is made mainly from young leaves and buds rather than roasted seeds.

Q52. Which vegetable is an edible modified stem tuber?

[RRB Group D — Practice]

1. Carrot
2. Potato
3. Radish
4. Turnip

Answer: (B) Potato

Explanation: Potato tubers are swollen underground stems bearing nodes or eyes that can sprout. Carrot, radish and turnip are primarily storage roots. Distinguishing plant organs explains differences in propagation, storage and uses in food markets and agricultural systems.

Q51. Which vegetable is a storage root rather than a stem tuber?

[RRB NTPC — Practice]

1. Potato
2. Ginger
3. Sweet potato
4. Turmeric

Answer: (C) Sweet potato

Explanation: Sweet potato, Ipomoea batatas, forms enlarged storage roots. Potato is a stem tuber, whereas ginger and turmeric produce rhizomes. Though all grow underground, their anatomical origins differ and influence vegetative propagation and food storage.

Q50. Cauliflower is chiefly consumed for which modified plant structure?

[MPPSC — Practice]

1. Immature inflorescence
2. Taproot
3. Seed coat
4. Bark

Answer: (A) Immature inflorescence

Explanation: The edible cauliflower head consists of a compact, undeveloped inflorescence and associated floral tissues. It belongs to Brassica oleracea. This differs from spinach, harvested for leaves, and potato, harvested for an underground stem tuber.

Q49. Which botanical name corresponds to mango?

[UPPCS — Practice]

1. Psidium guajava
2. Mangifera indica
3. Carica papaya
4. Annona squamosa

Answer: (B) Mangifera indica

Explanation: Mangifera indica is the mango tree, cultivated for its fleshy edible fruits and valued in horticulture and processing. Psidium guajava is guava, Carica papaya is papaya and Annona squamosa is custard apple.

Q48. Which fruit-producing plant is scientifically called Carica papaya?

[RAS — Practice]

1. Mango
2. Banana
3. Papaya
4. Guava

Answer: (C) Papaya

Explanation: Carica papaya is papaya, a fruit crop also valued as a source of the proteolytic enzyme papain from its latex. Papain has food-processing and other industrial applications. Mango, banana and guava belong to different genera.

Q47. Which plant is the traditional source of the antimalarial alkaloid quinine?

[SSC CGL — Practice]

1. Cinchona
2. Tulsi
3. Neem
4. Sandalwood

Answer: (A) Cinchona

Explanation: Quinine was obtained historically from the bark of Cinchona trees and became an important antimalarial drug. Its medicinal significance illustrates how economically useful plant metabolites inspired modern pharmacology. Treatment for malaria today depends on clinical guidance and parasite susceptibility.

Q46. Rauvolfia serpentina is economically important primarily because it contains which alkaloid?

[WBCS — Practice]

1. Caffeine
2. Reserpine
3. Morphine
4. Nicotine

Answer: (B) Reserpine

Explanation: Rauvolfia serpentina, commonly called sarpagandha, contains reserpine and related alkaloids. These compounds historically had medicinal uses, including management of hypertension. Their potent effects and adverse reactions make unsupervised use unsafe; plant origin alone does not guarantee safety.

Q45. Which medicinal plant is known botanically as Withania somnifera?

[CGPSC — Practice]

1. Ashwagandha
2. Brahmi
3. Tulsi
4. Amla

Answer: (A) Ashwagandha

Explanation: Withania somnifera is commonly called ashwagandha. Its roots are used in traditional medicinal preparations, and the plant is commercially cultivated. Scientific studies assess its chemical constituents, but traditional reputation does not automatically establish effectiveness or safety for every condition.

Q44. The tree Terminalia arjuna is best known for the traditional use of its which part?

[UPSC NDA — Practice]

1. Seeds
2. Flowers
3. Bark
4. Leaf hairs

Answer: (C) Bark

Explanation: Terminalia arjuna is a timber and medicinal tree whose bark has an established history in traditional cardiovascular preparations. Such products should not substitute prescribed treatment. The example demonstrates that bark, not only leaves or fruits, can carry commercial medicinal importance.

Q43. The plant commonly called amla is identified scientifically as which species?

[RRB NTPC — Practice]

1. Phyllanthus emblica
2. Cocos nucifera
3. Cajanus cajan
4. Dalbergia sissoo

Answer: (A) Phyllanthus emblica

Explanation: Amla, also called Indian gooseberry, is Phyllanthus emblica; the name Emblica officinalis is a synonym. Its fruit is consumed fresh or processed into preserves and traditional products. It is valued for ascorbic acid and other naturally occurring compounds.

Q42. Jute fibre is mainly extracted from which plant tissue?

[SSC MTS — Practice]

1. Stem bast
2. Flower petals
3. Fruit pulp
4. Root cap

Answer: (A) Stem bast

Explanation: Commercial jute is a bast fibre obtained from tissues of the stem, particularly phloem-associated fibres. Plants are commonly retted to separate fibre bundles. Jute is used in sacks, ropes, geotextiles and packaging because it is strong and biodegradable.

Q41. Cotton fibres are botanically what kind of structures?

[SSC CHSL — Practice]

1. Seed epidermal hairs
2. Root nodules
3. Leaf veins
4. Stem vascular bundles

Answer: (A) Seed epidermal hairs

Explanation: Cotton lint consists of elongated epidermal hairs that grow from the seed coat of Gossypium plants. After harvesting, ginning separates lint from seeds. The fibres are spun and woven, while cottonseed may yield oil and animal-feed products.

Q40. Which fibre is obtained commercially from the husk of coconuts?

[RPSC — Practice]

1. Coir
2. Jute
3. Flax
4. Silk

Answer: (A) Coir

Explanation: Coir is extracted from the fibrous mesocarp or husk of coconut fruits. It is used in ropes, mats, mattresses and horticultural growing media. Unlike cotton seed hairs or jute stem bast, coir is a fruit-husk fibre.

Q39. Crotalaria juncea is grown commercially mainly for which purpose?

[UPSC CDS — Practice]

1. Sunn hemp fibre and green manure
2. Coffee beans
3. Quinine-rich bark
4. Edible potato tubers

Answer: (A) Sunn hemp fibre and green manure

Explanation: Crotalaria juncea, known as sunn hemp, provides useful stem fibre for ropes and other products. It is also cultivated as green manure and a cover crop because it grows quickly and contributes biomass and soil-management benefits.

Q38. Which plant is widely cultivated as a source of teak timber?

[RRB Group D — Practice]

1. Tectona grandis
2. Coffea arabica
3. Glycine max
4. Cicer arietinum

Answer: (A) Tectona grandis

Explanation: Tectona grandis supplies teak, a durable hardwood widely used for furniture, doors and construction. Its timber is valued for workability and natural durability. Unlike annual food crops, timber trees require longer growth cycles and careful forest or plantation management.

Q37. Shisham timber is obtained from which tree?

[MPPSC — Practice]

1. Dalbergia sissoo
2. Cedrus deodara
3. Carica papaya
4. Zea mays

Answer: (A) Dalbergia sissoo

Explanation: Dalbergia sissoo, commonly called shisham or Indian rosewood, provides hardwood used in furniture and carpentry. It is especially associated with riverine and subtropical landscapes in the Indian subcontinent. Cedrus deodara supplies deodar timber instead.

Q36. The desert tree khejri has which botanical name?

[RAS — Practice]

1. Prosopis cineraria
2. Shorea robusta
3. Tectona grandis
4. Corchorus capsularis

Answer: (A) Prosopis cineraria

Explanation: Prosopis cineraria, or khejri, is economically and ecologically important in the Thar Desert. It provides fodder, fuelwood and edible pods called sangri. Its suitability for arid landscapes makes it significant to traditional agroforestry systems in Rajasthan.

Q35. Which botanical name denotes sal, an important timber tree?

[WBCS — Practice]

1. Shorea robusta
2. Dalbergia sissoo
3. Cocos nucifera
4. Coffea arabica

Answer: (A) Shorea robusta

Explanation: Shorea robusta is sal, a major forest tree yielding strong timber used in construction and other products. Sal-dominated forests also support ecosystem services and livelihoods. Scientific identification helps distinguish sal from teak and shisham in forestry questions.

Q34. Which resin-producing medicinal plant is known as guggul?

[SSC CGL — Practice]

1. Commiphora wightii
2. Papaver somniferum
3. Pisum sativum
4. Daucus carota

Answer: (A) Commiphora wightii

Explanation: Commiphora wightii is the guggul plant, valued for a fragrant gum-resin traditionally used in medicinal formulations. It grows in arid regions, and unsustainable resin extraction can threaten natural populations. Commercial demand therefore makes cultivation and conservation particularly important.

Q33. Which statement about natural rubber is correct?

[UPSC CSE — Practice]

1. It is extracted mainly from mineral ores
2. It is largely polyisoprene obtained from latex
3. It is the same as jute bast fibre
4. It is extracted from wheat grains

Answer: (B) It is largely polyisoprene obtained from latex

Explanation: Natural rubber is composed mainly of cis-1,4-polyisoprene and is harvested as latex, especially from Hevea brasiliensis. The latex is processed into useful elastic material. Rubber differs chemically and structurally from cellulose-based plant fibres such as cotton and jute.

Q32. Which state accounts for about three-fourths of India’s jute production?

[RRB NTPC UG CBT-I — 2026]

1. West Bengal
2. Bihar
3. Assam
4. Odisha

Answer: (A) West Bengal

Explanation: West Bengal dominates Indian jute cultivation because of fertile alluvial soils, a warm and humid climate and ready access to river water. The Hooghly belt also developed processing mills and transport links, creating a historically important jute economy.

Q31. Which industry uses cotton as a principal raw material?

[RRB NTPC UG CBT-I — 2026]

1. Textile industry
2. Iron and steel industry
3. Cement industry
4. Mining industry

Answer: (A) Textile industry

Explanation: Cotton supplies natural cellulose fibre to textile manufacturing. Ginning separates fibre from seeds, spinning produces yarn and weaving or knitting creates fabric. Cotton cultivation and processing link agriculture with large-scale industrial employment and consumer clothing production.

Q30. Which crop group received a six-year support plan announced in the Union Budget 2025–26 to reduce imports?

[RRB Group D — 2026]

1. Electronics
2. Steel
3. Pulses
4. Oilseeds

Answer: (C) Pulses

Explanation: The Union Budget 2025–26 proposed a six-year mission to improve self-reliance in pulses. Pulses are economically important for affordable dietary protein, farmer income and soil systems. Production, procurement and post-harvest support can reduce dependence on imported supplies.

Q29. The Harappans were among the earliest people in Eurasia to cultivate which crop?

[SSC CHSL Tier-I — 2025]

1. Tobacco
2. Chilli
3. Potato
4. Cotton

Answer: (D) Cotton

Explanation: Archaeological evidence from the Indus civilisation indicates early cultivation and use of cotton in South Asia. Cotton fibres could be spun and woven into textiles. Tobacco, chillies and potatoes reached the Indian subcontinent much later through post-Columbian exchanges.

Q28. Shisal or sisal craft mainly uses material originating from which source?

[CGPSC Prelims — 2025]

1. Plants
2. Bottle gourds
3. Seashells
4. Soil

Answer: (A) Plants

Explanation: Sisal fibre comes from the long leaves of Agave sisalana and related agaves. Its strength makes it useful for cords, ropes, mats and handicrafts. The plant origin explains why sisal is classified as a natural vegetable fibre.

Q27. What was Rajasthan’s share of India’s total bajra production in 2021–22, as asked in the examination?

[RPSC RAS Prelims — 2025]

1. 46.30%
2. 87.69%
3. 38.98%
4. 34.69%

Answer: (C) 38.98%

Explanation: The examination used the 2021–22 statistical figure of 38.98 percent. Pearl millet is suited to dry environments and forms a major part of Rajasthan’s cereal economy. This percentage refers to the specified historical agricultural year, not a current production estimate.

Q26. What is the principal aim of the Atmanirbhar Oil Seeds Abhiyan described in the exam?

[RRB NTPC UG CBT-I — 2025]

1. Export only surplus oilseeds
2. Self-sufficiency in oilseed production
3. Subsidise all edible oil prices
4. Import all seed varieties

Answer: (B) Self-sufficiency in oilseed production

Explanation: The initiative focuses on raising domestic oilseed production and reducing reliance on imports. Groundnut, soybean, mustard and sunflower contribute to edible-oil supply chains. Increased productivity and better processing can support farmers as well as food-security goals.

Q25. Which plant is traditionally used for relief from cold and cough?

[SSC CGL Tier-I — 2024]

1. Tulsi
2. Babool
3. Jamun
4. Arjun

Answer: (A) Tulsi

Explanation: Tulsi, commonly associated with Ocimum tenuiflorum or O. sanctum, has a long history in traditional remedies for respiratory symptoms. Its leaves contain aromatic compounds. Such traditional use does not replace evidence-based assessment or medical treatment when symptoms are significant.

Q24. The medicinal Himalayan yew, Taxus wallichiana, is found in which state among these options?

[SSC CGL Tier-I — 2024]

1. Goa
2. Jharkhand
3. Himachal Pradesh
4. Bihar

Answer: (C) Himachal Pradesh

Explanation: Taxus wallichiana occurs in Himalayan environments, including Himachal Pradesh. Yew species are important because taxane compounds inspired or supplied anticancer medicines. Conservation is critical because excessive harvesting and slow growth can threaten natural populations.

Q23. Ebony, mahogany and cinchona are characteristic trees of which forest type in India?

[SSC MTS — 2024]

1. Tropical deciduous forests
2. Thorn forests
3. Mangrove forests
4. Tropical evergreen forests

Answer: (D) Tropical evergreen forests

Explanation: Tropical evergreen forests develop in humid regions with high rainfall and contain diverse tall trees. Ebony and mahogany are valued for timber, while cinchona has medicinal importance. The question connects forest ecology with commercially useful plant resources.

Q22. Which statement about Indian black cotton soil is incorrect?

[UPSC NDA II GAT — 2024]

1. It is also called regur
2. It retains moisture strongly
3. It commonly contains lime
4. It has little clay and therefore supports every type of crop

Answer: (D) It has little clay and therefore supports every type of crop

Explanation: Regur soil is rich in clay and holds water effectively, making it well associated with cotton agriculture. Its heavy texture can complicate tillage when wet. The suggestion that it has very little clay is therefore incorrect.

Q21. Which kharif crop and Rajasthan production districts are correctly matched?

[RPSC Assistant Professor General Studies — 2024]

1. Wheat — Ganganagar, Hanumangarh, Baran
2. Maize — Sikar, Jalore, Dholpur
3. Bajra — Alwar, Barmer, Jaipur
4. Cotton — Dholpur, Jalore, Pratapgarh

Answer: (C) Bajra — Alwar, Barmer, Jaipur

Explanation: The listed bajra-producing districts are Alwar, Barmer and Jaipur. Pearl millet is a kharif crop adapted to relatively hot and dry areas. Its food and fodder value makes it central to agricultural livelihoods across parts of Rajasthan.

Q20. What is the main textile fibre crop of India among these choices?

[WBCS Executive Prelims (2023) — 2023]

1. Jute
2. Cotton
3. Flax
4. Sesame

Answer: (B) Cotton

Explanation: Cotton is a major commercial fibre crop supplying India’s textile sector. Its lint is made of seed hairs that are processed into yarn and fabrics. Jute is another important natural fibre, but cotton has a broader role in textile manufacturing.

Q19. Which one of these crops is normally grown during the kharif season?

[SSC CHSL Tier-I — 2023]

1. Gram
2. Mustard
3. Wheat
4. Cotton

Answer: (D) Cotton

Explanation: Cotton is generally cultivated during the warm monsoon-associated kharif season in much of India. Gram, mustard and wheat are commonly treated as rabi crops. Kharif and rabi groupings reflect rainfall, temperature and typical sowing schedules.

Q18. Industries using cotton, jute, tea, sugar, coffee and edible oil as raw materials are classified as what?

[SSC CHSL Tier-I — 2023]

1. Key industries
2. Consumer industries
3. Agro-based industries
4. Mineral-based industries

Answer: (C) Agro-based industries

Explanation: These industries draw their raw materials mainly from agricultural crops or plant products. Examples include textile mills, sugar factories, tea processing and vegetable-oil extraction. They are therefore agro-based industries rather than mineral-dependent manufacturing industries.

Q17. Which district ranked first in cotton production in Madhya Pradesh during 2020–21, according to the paper?

[MPPSC State Service Prelims — 2023]

1. Damoh
2. Khargone
3. Mandla
4. Panna

Answer: (B) Khargone

Explanation: Khargone was identified as the leading cotton-producing district for the specified 2020–21 period. Cotton is an important cash crop in the Nimar region. The question concerns a dated district-level agricultural statistic rather than a permanent ranking.

Q16. Which industry is especially concentrated on the banks of the Hooghly River?

[RRB Group D — 2022]

1. Sugar industry
2. Dairy industry
3. Iron-ore industry
4. Jute industry

Answer: (D) Jute industry

Explanation: The Hooghly basin became a major centre of jute mills because raw jute was available nearby. River water, port access, transport networks and a labour force encouraged industrial growth. Jute mills produce bags, ropes, cloth and other fibre goods.

Q15. Which state and plantation crop are correctly matched?

[UPPSC Combined State Prelims — 2022]

1. Gujarat — Tea
2. Uttar Pradesh — Jute
3. Kerala — Rubber
4. Assam — Wheat

Answer: (C) Kerala — Rubber

Explanation: Kerala has long been an important natural-rubber growing state, benefiting from a warm, wet tropical climate. Natural rubber is harvested mainly from latex-producing trees, particularly Hevea brasiliensis. Tea is strongly associated with Assam rather than Gujarat.

Q14. Which of the following is not a natural acid–base indicator?

[RRB Group D — 2022]

1. Turmeric
2. Hydrangea petal extract
3. Petunia petal extract
4. Methyl orange

Answer: (D) Methyl orange

Explanation: Turmeric pigments and some coloured flower extracts respond to changing acidity and can serve as natural indicators. Methyl orange is a synthetic indicator used in laboratory chemistry. This practical application demonstrates an economic and educational use of plant pigments.

Q13. Which plant fibre is popularly called the golden fibre?

[RRB NTPC CBT-I — 2021]

1. Mustard
2. Sandalwood
3. Wheat
4. Jute

Answer: (D) Jute

Explanation: Jute is called the golden fibre because of its characteristic sheen and historical commercial value. The fibre is extracted from the stems of Corchorus plants. It is widely used to manufacture sacks, twine, mats and biodegradable packaging materials.

Q12. Which crop is associated with the growing seasons Aus, Aman and Boro?

[UPSC CDS General Knowledge — 2021]

1. Wheat
2. Rice
3. Pulses
4. Cotton

Answer: (B) Rice

Explanation: Aus, Aman and Boro are seasonal categories of rice cultivation, especially in eastern India and Bangladesh. They differ in sowing, water availability and harvest periods. Their existence shows how one economically vital crop is adapted to different local cropping calendars.

Q11. Which state was the largest producer of raw jute in India in 2018–19?

[SSC CHSL 2020 paper — 2020]

1. West Bengal
2. Nagaland
3. Rajasthan
4. Bihar

Answer: (A) West Bengal

Explanation: West Bengal led raw-jute production in the specified 2018–19 period. The crop grows well in the warm, wet alluvial plains of eastern India. The state’s jute mills convert fibres into sacks, textiles and other commercially valuable products.

Q10. According to Rajasthan’s 2016–17 agricultural statistics, which is the correct descending production order of wheat, bajra, maize and rice?

[RPSC Senior Teacher Grade II — 2019]

1. Wheat, maize, rice, bajra
2. Wheat, rice, maize, bajra
3. Wheat, bajra, maize, rice
4. Wheat, maize, bajra, rice

Answer: (C) Wheat, bajra, maize, rice

Explanation: In the specified 2016–17 statistical reference, wheat ranked ahead of bajra, followed by maize and rice. Rajasthan grows substantial wheat under irrigation and bajra in drier environments. The answer is tied specifically to that reporting year.

Q9. Most of India’s jute factories have historically been situated in which state?

[RPF Constable 2018 paper — 2018]

1. Andhra Pradesh
2. Bihar
3. Assam
4. West Bengal

Answer: (D) West Bengal

Explanation: West Bengal became the centre of India’s jute manufacturing sector, especially along the Hooghly. Proximity to fibre-growing regions, transport, water and Kolkata’s port stimulated development. The mills turn plant bast fibre into packaging and textile materials.

Q8. Match the plant products to their chief sources: opium, hing, rubber and quinine. Which pairing is correct?

[UPPSC Civil Service Prelims (2017) — 2017]

1. Opium—bark; hing—root; rubber—fruit; quinine—stem
2. Opium—fruit; hing—root; rubber—stem; quinine—bark
3. Opium—stem; hing—root; rubber—bark; quinine—fruit
4. Opium—root; hing—stem; rubber—fruit; quinine—bark

Answer: (B) Opium—fruit; hing—root; rubber—stem; quinine—bark

Explanation: Opium is collected from the latex of unripe poppy capsules, hing from Ferula root exudates, rubber from stem latex and quinine from cinchona bark. These examples show how different plant organs yield economically valuable secondary products.

Q7. Which listed region is not known primarily for cotton-textile manufacturing?

[UPSC NDA GAT — 2017]

1. Mumbai–Pune
2. Madurai–Coimbatore
3. Dhanbad–Jamshedpur
4. Indore–Ujjain

Answer: (C) Dhanbad–Jamshedpur

Explanation: Dhanbad–Jamshedpur is especially associated with coal mining, iron and steel and heavy industries. The other regions have established cotton-textile activity. Industrial locations reflect access to raw cotton, workers, infrastructure, markets and historical investment.

Q6. The alkaloid caffeine occurs naturally in which beverages?

[UPPSC Civil Service Prelims (2016) — 2016]

1. Only tea
2. Only coffee
3. Both tea and coffee
4. Only lemon water

Answer: (C) Both tea and coffee

Explanation: Caffeine is a naturally occurring stimulant found in both tea leaves and coffee seeds. It affects alertness through the central nervous system. Concentrations vary with species, preparation and serving size, contributing to the commercial appeal of these beverages.

Q5. Which one is best classified as a cash crop among these?

[RPSC AEn DLB Civil (2016) — 2016]

1. Barley
2. Wheat
3. Tea
4. Rice

Answer: (C) Tea

Explanation: Tea is typically cultivated as a commercial plantation crop and processed for sale in domestic and export markets. Barley, wheat and rice are primarily food grains. The distinction describes the crop’s main economic purpose rather than whether it is edible.

Q4. Arrange these cotton-industry innovations from earliest to latest: spinning jenny, flying shuttle, spinning mule, water frame.

[UPSC NDA GAT — 2015]

1. Spinning jenny, spinning mule, water frame, flying shuttle
2. Flying shuttle, spinning jenny, water frame, spinning mule
3. Water frame, spinning jenny, spinning mule, flying shuttle
4. Flying shuttle, water frame, spinning jenny, spinning mule

Answer: (B) Flying shuttle, spinning jenny, water frame, spinning mule

Explanation: John Kay’s flying shuttle preceded James Hargreaves’s spinning jenny, Richard Arkwright’s water frame and Samuel Crompton’s spinning mule. These mechanisations accelerated yarn and cloth production, transforming the economic value and processing scale of raw cotton.

Q3. Which state was the leading producer of natural rubber in India among these choices?

[UPPSC Assistant Engineer General Studies (2013) — 2013]

1. Kerala
2. Karnataka
3. Tamil Nadu
4. Telangana

Answer: (A) Kerala

Explanation: Kerala has historically been India’s largest natural-rubber producing state. High rainfall, warmth and suitable plantation conditions favour rubber trees. Latex processing supports tyres and numerous other industries. Production rankings vary over time and the examination refers to its historical context.

Q2. Which of these high-yielding crop varieties are varieties of wheat: 1. Arjun, 2. Jaya, 3. Padma, 4. Sonalika?

[UPSC CSE Prelims GS-I (2002) — 2002]

1. 1 and 2 only
2. 2 and 3 only
3. 1 and 4 only
4. 3 and 4 only

Answer: (C) 1 and 4 only

Explanation: Arjun and Sonalika are wheat varieties, while Jaya and Padma are associated with rice. Identifying high-yielding varieties is important in crop improvement and Green Revolution history. A variety name must be associated with its correct cereal species.

Q1. Which of the following can be propagated by stem cuttings: Bougainvillea, carnations, cocoa and grapes?

[UPSC CSE Prelims GS-I (2002) — 2002]

1. Bougainvillea and carnations only
2. Carnations, cocoa and grapes only
3. Bougainvillea, cocoa and grapes only
4. All four

Answer: (D) All four

Explanation: Stem cuttings can develop adventitious roots and produce new plants from vegetative tissues. Bougainvillea, carnations, cocoa and grapes can be propagated using appropriate cutting methods. Vegetative multiplication helps growers preserve desirable characteristics of commercially useful varieties.