1: What is the common name for the subgenus Streptocarpus?
A: Cape primrose
B: African violet
C: Nodding violet
D: Primula
Correct Answer: A
Explanation: The common name for subgenus Streptocarpus is Cape primrose due to their resemblance to the unrelated Primula genus and their nativity to Cape in South Africa.
2: Which molecular family does Streptocarpus belong to?
A: Rosaceae
B: Gesneriaceae
C: Asteraceae
D: Lamiaceae
Correct Answer: B
Explanation: Streptocarpus is part of the Gesneriaceae family, known for its unique flowering plants.
3: Streptocarpus species can be mainly found in which regions?
A: South America
B: Southeast Asia
C: Afrotropical regions
D: Europe
Correct Answer: C
Explanation: Streptocarpus is native to Afrotropical regions including central, eastern, and southern Africa, Madagascar, and the Comoro Islands.
4: How many species of Streptocarpus are currently recognized?
A: About 100
B: About 155
C: About 200
D: About 255
Correct Answer: B
Explanation: Currently, about 155 species of Streptocarpus are recognized.
5: Streptocarpus flowers are often described as having what shape?
A: Bell-shaped
B: Tubular
C: Salverform
D: Star-shaped
Correct Answer: C
Explanation: Streptocarpus flowers are five-lobed and salverform, which means they are shaped like a tube that flares out at the mouth.
6: African violets evolved from which subgenus of Streptocarpus?
A: Streptocarpus
B: Streptocarpella
C: Saintpaulia
D: Polyanthus
Correct Answer: B
Explanation: DNA studies have shown that African violets evolved from within the Tanzanian Streptocarpus subgenus Streptocarpella.
7: Which type of Streptocarpus has more than one leaf and is called plurifoliate?
A: Unifoliate
B: Rosulate
C: Tubular
D: Bifoliate
Correct Answer: B
Explanation: The rosulate type is perennial and consists of a basal rosette of leaves, fitting the description of plurifoliate Streptocarpus with more than one leaf.
8: What is the overarching shape of Streptocarpus seed pods?
A: Spiral
B: Smooth
C: Squarish
D: Blistered
Correct Answer: A
Explanation: Streptocarpus seed pods have a helical or spiral form, similar to the “tusk” shape of a narwhal.
9: What range of temperatures is optimal for growing Streptocarpus?
A: 10–15 °C
B: 15–20 °C
C: 18–25 °C
D: 25–30 °C
Correct Answer: C
Explanation: The ideal temperature range for growing Streptocarpus is 18–25 °C.
10: What is the common name for Streptocarpus sect. Saintpaulia?
A: Cape primrose
B: African violet
C: Nodding violet
D: Winter rose
Correct Answer: B
Explanation: The section Saintpaulia within the subgenus Streptocarpella is commonly known as African violet.
11: What type of pollinators are Streptocarpus flowers evolved to attract mainly?
A: Beetles
B: Birds, flies, and butterflies
C: Wind
D: Bats
Correct Answer: B
Explanation: Streptocarpus flowers are designed to attract birds, long-tongued flies, butterflies, and potentially bees for pollination.
12: Streptocarpus subgenus Streptocarpella’s flowers are limited to what color range?
A: Reds and oranges
B: Blues and greens
C: Mid-purples, pale pinks, and whites
D: Yellows and browns
Correct Answer: C
Explanation: The color range for Streptocarpella flowers is mid-purples, pale pinks, and whites.
13: Which plant propagation method is most unique to Streptocarpus?
A: Cuttings
B: Seeds
C: Plantlets from roots
D: Layering
Correct Answer: C
Explanation: Unique to Streptocarpus, some species produce plantlets from the roots, which can be used for propagation.
14: What type of rooting hormone does Streptocarpus leaves naturally contain?
A: Auxin
B: Cytokinin
C: Gibberellin
D: Abscisic acid
Correct Answer: B
Explanation: Streptocarpus leaves naturally have a high concentration of cytokinin, which aids in rooting.
15: What type of plants are Streptocarpus ‘Chorus Line’ and ‘DS-Heart of Kai’ examples of?
A: Rosulate hybrids
B: Caulescent varieties
C: Tubular flowers
D: Double-flowered varieties
Correct Answer: D
Explanation: ‘Chorus Line’ and ‘DS-Heart of Kai’ are examples of double-flowered varieties of Streptocarpus.
16: What is a unique trait of some perennial unifoliate Streptocarpus in winter?
A: Total leaf shedding
B: Formation of a new plant
C: Creation of abscission lines partway down the leaf
D: Production of extra flowers
Correct Answer: C
Explanation: Some perennial unifoliate Streptocarpus form abscission lines partway down the leaf in winter.
17: What is the primary threat to Streptocarpus plants concerning care?
A: Overexposure to sunlight
B: Too wet soil
C: Too cold temperatures
D: Pest infestations
Correct Answer: B
Explanation: Streptocarpus plants do not thrive in soil that is too wet and require well-draining conditions.
18: What is the optimal light condition for Streptocarpus cultivation?
A: Full sun
B: Medium to bright indirect light
C: Full shade
D: Direct midday sun
Correct Answer: B
Explanation: Streptocarpus thrive best in medium to bright indirect light.
19: What should be done with Streptocarpus plants once their flowers have finished blooming?
A: Leave them on the plant
B: Snip off the whole stem at the base
C: Add fertilizer
D: Cut off the base leaf
Correct Answer: B
Explanation: Once the last flower on the stem has finished blooming, the whole stem should be snipped off at the base.
20: What is a common propagation method for hybrid Streptocarpus?
A: Self-pollination
B: Leaf propagation
C: Seed sowing
D: Layering
Correct Answer: B
Explanation: The only reliable method to propagate hybrid Streptocarpus and retain their characteristics is by leaf propagation.
21: Which hybrid Streptocarpus cultivar is known for being a sport of S. johannis?
A: ‘Blue Frills’
B: ‘Falling Stars’
C: ‘Carys’
D: ‘Jessica’
Correct Answer: B
Explanation: ‘Falling Stars’ is a pale blue sport of Streptocarpus johannis.
22: What horticultural trait do some modern Streptocarpus hybrids exhibit?
A: Multi-colored and fragrant flowers
B: Increased soil moisture tolerance
C: Leafless growth habit
D: Non-flowering periods
Correct Answer: A
Explanation: Modern hybrids often exhibit multi-colored, fragrant flowers with a range of other unique traits.
23: Who was responsible for the introduction of Streptocarpus rexii to British gardens?
A: Sir John Kirk
B: Mr Bowie
C: Captain Garden
D: Mr Watson
Correct Answer: B
Explanation: Mr Bowie sent Streptocarpus rexii to Kew in 1824, making it the first Streptocarpus species to reach British gardens.
24: What is the main purpose of incorporating colchicine in Streptocarpus hybridization?
A: To color flowers
B: To induce polyploidy and introduce new traits
C: To prevent pests
D: To increase flower size
Correct Answer: B
Explanation: Colchicine is used in hybridization to induce polyploidy, which helps introduce new traits to the hybrids.
25: What was the name of the first hybrid Streptocarpus recorded?
A: S. × Kewensis
B: S. × Dyeri
C: S. × Greenii
D: S. × Watsoni
Correct Answer: C
Explanation: The first hybrid Streptocarpus recorded was S. × Greenii, produced by crossing S. saundersii and S. rexii.
26: Which type of leaf arrangement can be found in Streptocarpus subgenus Streptocarpella?
A: Opposite
B: Decussate or ternate
C: Whorled
D: Rosulate
Correct Answer: B
Explanation: Streptocarpus subgenus Streptocarpella may have leaves arranged in decussate (90 degrees to preceding pairs) or ternate (whorls of three leaves) patterns.
27: Which hybrid Streptocarpus cultivar has gained the Royal Horticultural Society’s Award of Garden Merit for its violet-blue, striped flowers?
A: ‘Crystal Ice’
B: ‘Frosty Diamond’
C: ‘Kim’
D: ‘Bethan’
Correct Answer: D
Explanation: The hybrid cultivar ‘Bethan’ is noted for its violet-blue, striped flowers and has received the RHS Award of Garden Merit.
28: What feature characterizes the flowers of Streptocarpus subgenus Streptocarpus sect. Saintpaulia?
A: Absence of twisted fruit
B: Fragrant petals
C: Double-flowered forms
D: Winter bloom periods
Correct Answer: A
Explanation: Despite not having twisted fruit, African violets evolved from within the Tanzanian Streptocarpus subgenus Streptocarpella, specifically the section Saintpaulia.
29: What is a defining characteristic of the flowers in modern rosulate hybrids of Streptocarpus?
A: Extremely large petals
B: Three to several centimeters in diameter
C: Bi-lobed leaves
D: Leafless inflorescence
Correct Answer: B
Explanation: The flowers of modern rosulate hybrids are typically three to several centimeters in diameter.
30: Streptocarpus flowers are often described as zygomorphic. What does this mean?
A: Symmetrical in all directions
B: Radially symmetrical
C: Bilaterally symmetrical
D: Asymmetrical
Correct Answer: C
Explanation: Zygomorphic means that the flowers are bilaterally symmetrical, a common trait in Streptocarpus flowers.
31: Which color is yet to be achieved in Streptocarpus hybrid flowers?
A: Red
B: Blue
C: Orange
D: Purple
Correct Answer: C
Explanation: Despite various hybridization efforts, a true orange flower color has not yet been achieved in Streptocarpus hybrids.
32: During propagation, what is the method called where a Streptocarpus leaf is placed in water to root?
A: Layering
B: Water rooting
C: Softwood cuttings
D: Division
Correct Answer: B
Explanation: Water rooting is a method where Streptocarpus leaves are placed in a glass of water to develop roots.
33: Which hybrid cultivar of Streptocarpus is known for being very floriferous?
A: ‘Gloria’
B: ‘Canterbury Surprise’
C: ‘Falling Stars’
D: ‘Polka-Dot Purple’
Correct Answer: C
Explanation: ‘Falling Stars’ is a hybrid cultivar known for being very floriferous.
34: What is the recommended action if a Streptocarpus leaf shows blemishes?
A: Remove the whole leaf
B: Cut off only the blemished parts
C: Add more fertilizer
D: Move to darker location
Correct Answer: B
Explanation: For blemished leaves, it’s best practice to cut off only the blemished parts and trim the leaf to a normal shape.
35: What type of leaf does Streptocarpus unifoliates form?
A: Multiple leaves
B: A single continuously growing leaf
C: Clustered leaves
D: Spiny leaves
Correct Answer: B
Explanation: Unifoliates form a single leaf that grows continuously from the base.
36: In Streptocarpus hybridization, what is often used to induce mutations for new traits?
A: Fertilizers
B: Irradiation
C: Genetic crossing
D: Substrate adjustment
Correct Answer: B
Explanation: Irradiation such as X-rays or gamma rays is used to induce mutations in Streptocarpus plants to introduce new traits.
37: Which type of Streptocarpus propagation involves cutting segments of the leaf horizontally or lengthwise?
A: Seed propagation
B: Clump division
C: Leaf segment propagation
D: Root plantlet production
Correct Answer: C
Explanation: Leaf segment propagation involves cutting segments of a Streptocarpus leaf either horizontally or lengthwise and planting them.
38: What is a key characteristic of Streptocarpus anatomy concerning their anthers?
A: They are tightly bound
B: They are not present
C: They open slightly and act like a pepper shaker
D: They are purple
Correct Answer: C
Explanation: Streptocarpus anthers are loosely joined together and open slightly, acting like a pepper shaker to release pollen.
39: What attribute is noted about Streptocarpus ‘Crystal Ice’ hybrid?
A: Pink flowers with stripes
B: White flowers with blue veins
C: Yellow flowers with red spots
D: Blue flowers with white spots
Correct Answer: B
Explanation: Streptocarpus ‘Crystal Ice’ is known for its white flowers veined with violet-blue.
40: How can overwatering affect Streptocarpus?
A: Enhanced blooming
B: Root rot and health decline
C: Increased leaf growth
D: Delayed flowering
Correct Answer: B
Explanation: Overwatering Streptocarpus can lead to root rot and generally poor plant health.
41: What is the function of nectar guidelines in Streptocarpus flowers?
A: To repel pests
B: To guide pollinators to nectar
C: To attract predators
D: To shade the plant
Correct Answer: B
Explanation: Nectar guidelines on Streptocarpus flowers guide pollinators to the nectar, enhancing pollination efficiency.
42: Which historical figure sent Streptocarpus rexii to Kew Gardens in 1824?
A: Mr Bowie
B: Charles Darwin
C: Captain Garden
D: Sir John Kirk
Correct Answer: A
Explanation: Mr. Bowie sent the first Streptocarpus rexii to Kew Gardens in 1824.
43: What is a feature of the cultivar Streptocarpus ‘Gloria’?
A: Red and yellow flowers
B: Pale pink flowers
C: Large leaves
D: Extended blooming period
Correct Answer: B
Explanation: ‘Gloria’ is a hybrid Streptocarpus cultivar known for its pale pink flowers.
44: What plant condition can be indicated by the abscission lines formed on Streptocarpus leaves?
A: Pest infestation
B: Leaf nutrient deficiency
C: Seasonal transition
D: Overwatering
Correct Answer: C
Explanation: The formation of abscission lines on Streptocarpus leaves often indicates a seasonal transition, especially in winter.
45: What should be used to encourage Streptocarpus seed germination?
A: Direct sunlight
B: Clear plastic covering
C: Cold environment
D: High nitrogen fertilizer
Correct Answer: B
Explanation: Covering Streptocarpus seeds with clear plastic helps maintain humidity, which is essential for seed germination.
46: What is the growth habit of Streptocarpella plants?
A: Erect and tall
B: Clump-forming or trailing
C: Ground cover
D: Sprawling vines
Correct Answer: B
Explanation: Streptocarpella plants are generally clump-forming or trailing.
47: Which Streptocarpus cultivar is known for having a deep violet flower color?
A: ‘Charlotte’
B: ‘Kim’
C: ‘Blue Frills’
D: ‘Jessica’
Correct Answer: B
Explanation: ‘Kim’ is recognized for its deep violet flower color.
48: How are mature clumps of Streptocarpus typically propagated?
A: By seeds
B: By leaf cuttings
C: By root plantlets
D: By clump division
Correct Answer: D
Explanation: Mature clumps of Streptocarpus can be divided into smaller pieces and repotted for propagation.
49: What type of temperature suits Streptocarpus cultivation in winter for a rest?
A: Around 10 °C (50 °F) or less
B: Above 30 °C (86 °F)
C: Constant 25 °C (77 °F)
D: Below freezing
Correct Answer: A
Explanation: Streptocarpus can be taken down to around 10 °C or less in winter for a rest period.
50: What color are the flowers of Streptocarpus cultivar ‘Harlequin Blue’?
A: Pale pink
B: Soft blue, yellow, and purple line
C: Bright red
D: White with green veins
Correct Answer: B
Explanation: ‘Harlequin Blue’ features soft blue flowers with yellow and purple lines.
51: What term describes a Streptocarpus plant that only has one continuously growing leaf?
A: Plurifoliate
B: Rosulate
C: Unifoliate
D: Multifoliate
Correct Answer: C
Explanation: Unifoliate describes a Streptocarpus plant with a single, continuously growing leaf.
52: Who was His Majesty’s collector in South Africa and sent the first Streptocarpus rexii to Kew?
A: Mr Bowie
B: Captain Garden
C: Mr Watson
D: Sir John Kirk
Correct Answer: A
Explanation: Mr Bowie was His Majesty’s collector in South Africa who sent the first Streptocarpus rexii to Kew.
53: Which Streptocarpus feature helps it recover well from dehydration?
A: High water retention cells
B: Leaf wilting mechanism
C: Root growth surge
D: Enhanced photosynthesis
Correct Answer: B
Explanation: Streptocarpus plants recover well from dehydration due to their ability to wilt leaves slightly,
54: How can Streptocarpus be propagated by roots?
A: Air layering
B: Root plantlets
C: Tubular grafting
D: Offset planting
Correct Answer: B
Explanation: Some species produce plantlets from the roots which can be used to propagate the plant.
55: What unique flower shape is found in Streptocarpus hybrid ‘Anderson’s Crows’ Wings’?
A: Bell-shaped
B: Stellate
C: Zygomorphic with aberrant peloric flowers
D: Funnel-shaped
Correct Answer: C
Explanation: ‘Anderson’s Crows’ Wings’ exhibits both normal zygomorphic flowers and aberrant peloric flowers on the same plant.
56: What is the main purpose of molecular systematics in classifying Streptocarpus?
A: Creating visual appeal
B: Determining culinary uses
C: Conclusively showing taxonomic relationships
D: Identifying medicinal properties
Correct Answer: C
Explanation: Molecular systematics has shown conclusively which species truly belong to the genus Streptocarpus and exclude others like Damrongia orientalis.
57: Which Streptocarpus species was first to be described and is commonly used in early hybridization?
A: S. rexii
B: S. saxorum
C: S. liliputana
D: S. polyanthus
Correct Answer: A
Explanation: S. rexii was the first Streptocarpus species to be described and used extensively in early hybrid development.
58: How does the trait of forming abscission lines benefit Streptocarpus in winter?
A: Enhances flowering
B: Reduces water loss and energy expenditure
C: Increases leaf production
D: Prevents frost damage
Correct Answer: B
Explanation: Forming abscission lines helps reduce energy expenditure and water loss during winter.
59: What is a distinct characteristic of Streptocarpus ‘Jennifer’?
A: Pale violet-blue with darker veining
B: Pale yellow stripes
C: Deep red flowers
D: Speckled leaves
Correct Answer: A
Explanation: ‘Jennifer’ is known for its pale violet-blue flowers with darker veining.
60: What modern hybridizing goals are pursued for Streptocarpus flowers?
A: Edible flower production
B: Increased scent, varied flower forms, and extended flowering periods
C: Decreased size
D: Resistance to herbivores
Correct Answer: B
Explanation: Modern hybridizers aim to increase the range of flower forms, colors, scents, and flowering periods for Streptocarpus.