1. Castor belongs to which botanical family?
A. Malvaceae
B. Euphorbiaceae
C. Solanaceae
D. Fabaceae
Answer: B
Rationale: Castor (Ricinus communis) belongs to the family Euphorbiaceae.
2. The economic part of castor plant is:
A. Leaf
B. Stem
C. Seed
D. Root
Answer: C
Rationale: Castor seeds are the source of castor oil.
3. Castor oil is mainly used for:
A. Edible purpose
B. Lubricants and industrial products
C. Animal feed
D. Biofertilizer
Answer: B
Rationale: Castor oil is non-edible and widely used in lubricants, pharmaceuticals, and cosmetics.
4. The chromosome number of castor is:
A. 2n = 10
B. 2n = 20
C. 2n = 30
D. 2n = 40
Answer: B
Rationale: Castor has a diploid chromosome number of 2n = 20.
5. Castor is mainly grown as:
A. Kharif crop
B. Rabi crop
C. Summer crop
D. Perennial crop
Answer: A
Rationale: Castor is predominantly a Kharif crop in India.
6. The center of origin of castor is:
A. India
B. South America
C. Africa
D. China
Answer: C
Rationale: Africa is considered the primary center of origin of castor.
7. Castor is primarily pollinated by:
A. Insects
B. Wind
C. Water
D. Self-pollination
Answer: B
Rationale: Castor is predominantly wind-pollinated.
8. The inflorescence of castor is:
A. Panicle
B. Spike
C. Raceme
D. Capitulum
Answer: B
Rationale: Castor bears a terminal spike inflorescence.
9. Castor is a:
A. Monoecious plant
B. Dioecious plant
C. Hermaphrodite plant
D. Apomictic plant
Answer: A
Rationale: Male and female flowers are borne separately on the same plant.
10. Female flowers in castor are present at:
A. Lower part of spike
B. Middle part
C. Upper part
D. Entire spike
Answer: C
Rationale: Female flowers are borne on the upper portion of the spike.
11. Optimum temperature for castor growth is:
A. 10–15°C
B. 15–20°C
C. 20–30°C
D. 35–45°C
Answer: C
Rationale: Castor grows best under warm conditions of 20–30°C.
12. Castor prefers which soil type?
A. Sandy soil
B. Clay soil
C. Well-drained loamy soil
D. Waterlogged soil
Answer: C
Rationale: Well-drained loamy soils are ideal for castor cultivation.
13. Castor is sensitive to:
A. Drought
B. Frost
C. Salinity
D. Wind
Answer: B
Rationale: Frost severely damages castor plants.
14. Recommended seed rate for hybrid castor is:
A. 3–4 kg/ha
B. 5–6 kg/ha
C. 8–10 kg/ha
D. 12–15 kg/ha
Answer: A
Rationale: Hybrid castor requires a lower seed rate due to wider spacing.
15. Recommended spacing for hybrid castor is approximately:
A. 45 × 30 cm
B. 60 × 30 cm
C. 90 × 60 cm
D. 120 × 90 cm
Answer: C
Rationale: Wider spacing supports better branching and yield.
16. Castor is classified as:
A. Short-day plant
B. Long-day plant
C. Day-neutral plant
D. Shade-loving plant
Answer: C
Rationale: Castor is a day-neutral plant.
17. Major castor-producing state in India is:
A. Rajasthan
B. Gujarat
C. Andhra Pradesh
D. Maharashtra
Answer: B
Rationale: Gujarat is the leading producer of castor in India.
18. The oil content in castor seed is about:
A. 25–30%
B. 30–35%
C. 45–55%
D. 65–70%
Answer: C
Rationale: Castor seeds contain about 45–55% oil.
19. The toxic principle in castor seed is:
A. Aflatoxin
B. Ricin
C. Solanine
D. Nicotine
Answer: B
Rationale: Ricin is a highly toxic protein present in castor seed.
20. The recommended nitrogen dose for castor is:
A. Low
B. Medium
C. High
D. Zero
Answer: C
Rationale: Castor is a heavy feeder and responds well to nitrogen.
21. Castor is mainly grown under:
A. Irrigated conditions
B. Rainfed conditions
C. Greenhouse conditions
D. Flooded conditions
Answer: B
Rationale: Castor is mostly cultivated as a rainfed crop.
22. Intercropping with castor is commonly done with:
A. Rice
B. Wheat
C. Groundnut
D. Sugarcane
Answer: C
Rationale: Groundnut is commonly intercropped with castor.
23. The most common pest of castor is:
A. Stem borer
B. Semilooper
C. Aphid
D. Whitefly
Answer: B
Rationale: Castor semilooper (Achaea janata) is a major pest.
24. Major disease of castor is:
A. Powdery mildew
B. Wilt
C. Root rot
D. Leaf curl
Answer: B
Rationale: Fusarium wilt is a serious disease in castor.
25. Harvesting of castor is done:
A. At one time
B. In multiple pickings
C. Before maturity
D. Mechanically only
Answer: B
Rationale: Capsules mature unevenly, requiring multiple pickings.
26. Castor capsules are harvested when:
A. Green
B. Yellow
C. Brown and dry
D. Fully opened
Answer: C
Rationale: Capsules should be brown and dry to avoid seed damage.
27. The average yield of castor is:
A. 500–700 kg/ha
B. 800–1000 kg/ha
C. 1200–1500 kg/ha
D. 2000–2500 kg/ha
Answer: C
Rationale: Under good management, yields reach 1200–1500 kg/ha.
28. Castor oil contains a high proportion of:
A. Oleic acid
B. Linoleic acid
C. Ricinoleic acid
D. Palmitic acid
Answer: C
Rationale: Ricinoleic acid is the characteristic fatty acid of castor oil.
29. Castor oil is valued because it:
A. Is edible
B. Has drying properties
C. Has high viscosity
D. Is volatile
Answer: C
Rationale: High viscosity makes it ideal for lubricants.
30. Hybrid castor cultivation requires:
A. Isolation
B. Rogueing only
C. Cytoplasmic male sterility
D. Vegetative propagation
Answer: C
Rationale: CMS system is used in hybrid castor seed production.
31. Castor root system is:
A. Fibrous
B. Adventitious
C. Tap root
D. Rhizomatous
Answer: C
Rationale: Castor has a strong tap root system.
32. The male flowers of castor lack:
A. Stamens
B. Pistil
C. Sepals
D. Petals
Answer: B
Rationale: Male flowers do not have pistils.
33. Castor leaves are:
A. Simple
B. Pinnate
C. Palmate
D. Bipinnate
Answer: C
Rationale: Castor leaves are large and palmately lobed.
34. Castor seed coat is:
A. Smooth
B. Hairy
C. Mottled and glossy
D. Spiny
Answer: C
Rationale: Castor seeds are mottled and shiny.
35. Castor crop duration is approximately:
A. 60–70 days
B. 90–100 days
C. 120–180 days
D. 250–300 days
Answer: C
Rationale: Castor has a long duration of 4–6 months.
36. Best time of sowing castor in Kharif is:
A. April–May
B. June–July
C. August–September
D. October–November
Answer: B
Rationale: Onset of monsoon is ideal for castor sowing.
37. Castor is tolerant to:
A. Frost
B. Waterlogging
C. Drought
D. Salinity
Answer: C
Rationale: Castor is relatively drought tolerant.
38. Castor seed is classified as:
A. Orthodox
B. Recalcitrant
C. Intermediate
D. Viviparous
Answer: A
Rationale: Castor seeds can be dried and stored safely.
39. Oil extraction in castor is commonly done by:
A. Boiling
B. Solvent extraction
C. Cold pressing
D. Fermentation
Answer: B
Rationale: Solvent extraction ensures higher oil recovery.
40. Castor cake is mainly used as:
A. Animal feed
B. Human food
C. Organic manure
D. Biofuel
Answer: C
Rationale: Due to toxicity, castor cake is used as manure.
41. Castor is also known as:
A. Palma Christi
B. Queen of oils
C. Golden seed
D. Wonder bean
Answer: A
Rationale: Castor is traditionally called Palma Christi.
42. The stigma of castor flower is:
A. Smooth
B. Sticky and feathery
C. Hairless
D. Reduced
Answer: B
Rationale: Feathery stigma aids wind pollination.
43. Seed setting in castor is influenced mainly by:
A. Soil fertility
B. Wind speed
C. Insect activity
D. Rainfall
Answer: B
Rationale: Wind plays a key role in pollination.
44. Castor responds well to which micronutrient?
A. Iron
B. Zinc
C. Boron
D. Molybdenum
Answer: C
Rationale: Boron improves flowering and seed setting.
45. Castor oil solidifies at:
A. 0°C
B. –10°C
C. –18°C
D. –25°C
Answer: C
Rationale: Castor oil has a very low freezing point.
46. Castor crop is unsuitable for:
A. Black soils
B. Red soils
C. Waterlogged soils
D. Light soils
Answer: C
Rationale: Poor drainage leads to root diseases.
47. Castor is often called an industrial crop because:
A. It is edible
B. It has medicinal value only
C. It has diverse industrial uses
D. It grows in factories
Answer: C
Rationale: Castor oil is used in multiple industries.
48. Primary branch development in castor is promoted by:
A. Low nitrogen
B. High spacing
C. High plant density
D. Late sowing
Answer: B
Rationale: Wider spacing encourages branching.
49. The seed multiplication ratio in castor is:
A. Very low
B. Moderate
C. High
D. Zero
Answer: C
Rationale: Each plant produces many seeds, giving a high ratio.
50. Castor is best suited for:
A. Temperate climate
B. Tropical and subtropical climate
C. Alpine regions
D. Cold deserts
Answer: B
Rationale: Castor thrives in warm tropical and subtropical regions.
%20(2).png)
0 Comments