Botany Multiple Choice Questions and Answers

51. Urea is a source of

1. Phosphorous
2. Nitrogen
3. Potassium
4. All of the above

52. Water blooms are formed by

1. Lemna
2. Hydrilla
3. Water hyacinth
4. Planktonic algae.

53. Water logging of soil makes it physiologically dry because

1. This condition does not allow the capillary force to work
2. this condition does not allow oxygen to enter the soil
3. both a and b
4. none of these

54. What is the area in floriculture (in 1000 hectare) in India

1. 40 - 50
2. 60 - 80
3. 100 - 120
4. None of these

55. Which gas of the atmosphere holds up ultraviolet rays ?

1. O2
2. O2
3. N2
4. CO2.

56. Which is not a green house gas?

1. CFC
2. CH4
3. CO
4. H2

57. Which is not applicable to vegetatively propagated plants

1. To get true to type plants
2. To protect an elite quality
3. To conserve a plant
4. To get a new type of plant

58. Which one is green manure

1. Sesbania
2. Rice
3. Oat
4. Maize

59. Which one is the major component of Bordeaux mixture

1. Copper sulphate
2. Sodium chloride
3. Calcium chloride
4. Magnesium sulphate

60. Which one of the following is natural insecticide

1. Pyrethrum
2. Nicotine
3. both a and b
4. None of these