1.Which of the following is not a plant growth promoter?
a) Auxins
b) Gibberellins
c) Ethylene
d) Abscisic acid
Explanation: Abscisic acid
2. Who initiated the discovery of plant growth hormones?
a) Charles Darwin
b) Francis Darwin
c) Both (a) and (b)
d) None of these
Explanation: Both (a) and (b)
3.According to Charles Darwin, which plant would help in the discovery of PGH?
a) Larkspur
b) Buttercup
c) Canary grass
d) All of these
Explanation: Canary grass
4. Coleoptiles responded to ________
a) Light
b) Water
c) Touch
d) All of these
Explanation: Coleoptiles responded to light.
5. As a response to stimuli the coleoptiles caused ________
a) Bending
b) Flowering
c) Budding
d) All of these
Explanation: As a response to stimuli the coleoptiles caused bending.
6.Auxins are discovered by
a) Charles Darwin
b) Francis Darwin
c) F. W. Went
d) Both (a) and (b)
Explanation: Auxins are discovered by F. W. Went.
7. Gibberella fujikuroi causes what disease in rice plants?
a) Foolish seeding
b) Bikaner
c) Both (a) and (b)
d) None of these
Explanation: Both (a) and (b)
8.Who repotted that the symptoms reappeared in uninfected plants treated with sterile filtrate of
giberella fungus?
a) E. Kurosawa
b) F. Skoog
c) Both (a) and (b)
d) None of these
Explanation: E. Kurosawa
9. Callus from which plant was observed by miller?
a) Tomato
b) Tobacco
c) Rice plant
d) None of these
Explanation: Tobacco
10. Addition of what to auxins in nutrients medium causes proliferation of callus?
a) DNA
b) Yeast extract
c) Coconut milk
d) All of these
Explanation: All of these
11. The only gaseous PGR is ________
a) IBA
b) Kinetin
c) Terpenes
d) Ethylene
Explanation: The only gaseous PGR is Ethylene
12. The Greek meaning of ‘Auxein’ is ________
a) To flower
b) To seed
c) To grow
d) To enlarge
Explanation: To grow
13. Auxin was first isolated from ________
a) Frog’s wine
b) Zeatin
c) Human wine
d) None of these
Explanation: Auxin was first isolated from human wine.
14. The name ‘Auxin’ was given to which chemical?
a) Indole-3-acetic acid
b) Indole-6-acetic acid
c) Indole-3-butyric acid
d) Indole-6-butyric acid
Explanation: Indole-3-acetic acid
15. How many of the following auxins are obtained from plants?
IAA, IBA, NAA, 2, 4–D
a) 1
b) 2
c) 3
d) 4
Explanation: 2
16. NAA stands for ________.
a) Nitroacetic acid
b) Nitro aceto acetate
c) Naphthaleneacetic acid
d) Naphthaloaceto acetic acid
Explanation: NAA stands for Naphthaleneacetic acid
17. 2, 4–D stands for ________
a) 2, 4–Dichlorophenoxy acetate
b) 2, 4–Dextrophenoxy acetate
c) 2, 4–Diphosphenoxy acetate
d) 2, 4–Dichloromethoxy acetate
Explanation: 2, 4–Dichlorophenoxy acetate
18.Synthetic auxins are extesively used in
a) Agriculture
b) Horticulture
c) Both (a) and (b)
d) None of these
Explanation: Both (a) and (b)
19. Natural auxins are extensively used in
a) Agriculture
b) Horticulture
c) Both (a) and (b)
d) None of these
Explanation: Both (a) and (b)
20. Which effect of auxin is applied worldwide for plant propagation?
a) Apical dominance
b) Herbicidal action
c) Initiate rooting in stem cutting
d) None of these
Explanation: Initiate rooting in stem cutting
21. Auxins promote flowering in
a) Tomatoes
b) Pineapples
c) Oranges
d) None of these
Explanation: Auxins promote flowering in Pineapples.
22. What prevents the fruit and leaf to drop in early?
a) ABA
b) IAA
c) NAA
d) Both (b) and (c)
Explanation: Both (b) and (c)
23. What promotes the abscission of older mature leaf?
a) Abscisic acid
b) Auxin
c) Ethylene
d) Cytokinins
Explanation: Auxin promotes the abscission of older mature leaf.
24. In most of the higher plants, the growing apical bud inhibits the growth of lateral bud. This
phenomena is called
a) Apical tolerance
b) Axial intolerance
c) Apical ordinance
d) Apical dominance
Explanation: Apical dominance
25. What can help removing apical dominance?
a) Removal of shoot tips
b) Provide plants with a lot of auxin
c) Both (a) and (b)
d) None of these
Explanation: Removal of shoot tips
26. The process of removal of shoot tip to avoid apical dominance is called _______
a) Autotomy
b) Decapitation
c) Both (a) and (B)
d) Capitation
Explanation: The process of removal of shoot tip to avoid apical dominance is called Decapitation.
27. Decapitation is widely used for
a) Tea plantation
b) Hedge making
c) Both (a) and (b)
d) None of these
Explanation: Decapitation is widely used for tea plantation and hedge making.
28. Which of the following PGR can induce parthenocarpy?
a) IBA
b) 2, 4–D
c) Terpenes
d) Kinetin
Explanation: 2, 4–D
29. Auxins induce parthenocarpy in which plants?
a) Tomato
b) Pineapple
c) Apple
d) All of these
Explanation: Tomato
30. Which of the following PGR is widely used as herbicide?
a) Auxin
b) Gibberellic acid
c) Cytokinins
d) All of these
Explanation: Auxin
31. Which of the following PGR is widely used to kill dicotyledonous weeds?
a) IAA
b) NAA
c) 2, 4–D
d) ABA
Explanation: 2, 4–D
32. 2, 4–D does not show herbicidal action on
a) Chicory led ones
b) Monocotyledonous
c) Mature dicotyledonous
d) Mature monocotyledonous
Explanation: 2, 4–D does not show herbicidal action on monocotyledonous.
33. Auxin 2, 4–D is used for what?
a) To remove weeds from farms by formers
b) To remove weeds from lawn by gardeners
c) To induce flowering in horticulture
d) All of these
Explanation: To remove weeds from lawn by gardeners
34. Auxin helps in what?
a) Controlling phloem differentiation
b) Controlling xylem differentiation
c) Cell division
d) Both (b) and (c)
Explanation: Both (b) and (c)
35. How many varieties of gibberellins reported from widely different variety of organisms?
a) 100
b) 120
c) 145
d) 140
Explanation: 100 varieties
36. Different types of gibberellins is reported from what kind of organisms?
a) Fungi
b) Higher plants
c) Both (a) and (b)
d) None of these
Explanation: Both (a) and (b)
37. Which of the following was first reported gibberellins to be discovered?
a) \[GA_{1}\]
b) \[GA_{2}\]
c) \[GA_{3}\]
d) \[GA_{4}\]
Explanation: \[GA_{3}\]
38. What is the chemical natural of all the gas?
a) Basic
b) Acidic
c) Neutral
d) Slightly basic
Explanation: Acidic
39. Gibberellins bring about what kind of change in plants?
a) Morphological
b) Physiological
c) Genetical
d) None of these
Explanation: Physiological
40. Which ability of gibberellins is used to increase the length of grape stalks?
a) Ability to increase apically
b) Ability to increase in length of axis
c) Ability to avoid apical dominance
d) All of these
Explanation: Ability to increase in length of axis
41.How does gibberellins not change the quality of an apple?
a) Make it sweeter
b) Elongate it in size
c) Improve its shape
d) All of these
Explanation: Make it sweeter
42. How can gibberellins help to extend the market period?
a) It delays senescence
b) Increases ripening period
c) Increases flowering time
d) All of these
Explanation: It delays senescence
43. In the form of sugar, sugarcane stores what?
a) Proteins
b) Carbohydrates
c) Glycoproteins
d) None of these
Explanation: Carbohydrates
44. On spraying gibberellins on sugarcane crops what major change will it bring?
a) Increase sweetness
b) Increase length of stem
c) Increase root strength
d) All of these
Explanation: Increase length of stem
45. Spraying of gibberellins over sugarcane can increase the yield by how much?
a) 20 tonnes/acre
b) 20 kg/acre
c) 20 quintet/acre
d) None of these
Explanation: 20 tonnes/acre
46. What change does it bring in juvenile conifers when sprayed with gas?
a) Hastens maturity period
b) Hastens germination period
c) Hastens dormancy period
d) None of these
Explanation: Hastens maturity period
47. Spraying of gas on juvenile conifers causes
a) Early flowering
b) Early germination
c) Early seed production
d) All of these
Explanation: Spraying of gas on juvenile conifers causes early seed production.
48. Cytokinins have specific effects on
a) Cytokinosis
b) cytokinesis
c) Cytoketosis
d) Cytolysis
Explanation: Cytokinins have specific effects on cytokinesis.
49. In what form the cytokinins were discovered?
a) Terpenes
b) Toluenes
c) Kinetin
d) None of these
Explanation: Kinetin
50.Gibberellins promotes bolting in which plants?
a) Beet
b) Cabbage
c) Both (a) and (b)
d) None of these
Explanation: Both (a) and (b)