Chapter 22 - Techniques of Micropropagation

Question 1

In developed countries most micropropagation (MP) is of __________ plants?

Answer 1

in developing countries the focus is on food, fiber, forestry, and medicinal crops.

Question 2

the 5 advantages of MP over traditional propagation techniques

Answer 2

1. Mass propagation of specific clones.
2. Production of pathogen-free plants.
3. Clonal propagation of parental stock (inbred lines) for hybrid seed production.
4. Year-round nursery production.
5. Germplasm preservation.

Question 3

the 5 areas where the mass propagation aspects of MP are particularly useful

Answer 3

1. Where the propagation rate is slow by conventional means.
2. New cultivars with high market demand.
3. Cultivars with high market value.
4. Plants that are difficult to propagate clonally.
5. Conservation of endangered species.

Question 4

the 6 areas where MP can encounter problems/disadvantages

Answer 4

1. expensive and sophisticated facilities, trained personnel.
2. High labor costs.
3. A high-volume, adequate storage facilities to stock-pile products.
4. Pathogen contamination or insect infestation.
5. Variability and production of off-type individuals can be a risk in the products emerging from micropropagation. Careful field testing of new products, and continuing research and development
6. Economics and marketing are key to the success of commercial operations.

Question 5

What are the 3 areas a MP facility can be divided into?

Answer 5

preparation, transfer, and growing areas.

Question 6

What is an autoclave?

Answer 6

is a machine that uses steam under pressure to kill harmful bacteria, viruses, fungi, and spores on items that are placed inside a pressure vessel.

Question 7

What temperature/pressure/time is needed to ensure sterility?

Answer 7

120°C (250°F) at-least 30 minutes.

Question 8

What is a laminar flow hood/cabinet?

Answer 8

A cabinet that filters air through a HEPA filter to eliminate fungal and bacterial spores from tissue culture work spaces.

Question 9

What is a HEPA filter?

Answer 9

high-efficiency particulate air (HEPA) filter

Question 10

functions of Inorganic salts

Answer 10

Inorganic salts provide the macro elements (nitrogen, phosphorus, potassium, calcium, and magnesium) and micro elements (boron, cobalt, copper, manganese, iodine, iron, and zinc)

Question 11

functions of Sucrose

Answer 11

carbohydrate as an energy source

Question 12

functions of Vitamins (thiamin, nicotinic acid, pyridoxine, inositol)

Answer 12

vitamins to support plant enzyme reactions,

Question 13

functions of Citric/ascorbic acid

Answer 13

can be used as an anti browning agent (antioxidant)

Question 14

functions of Activated charcoal

Answer 14

to adsorb and counteract inhibiting substances released by some tissues.

Question 15

functions of Agar

Answer 15

to form a semi-solid base to support the explant.

Question 16

‘MS salts’ stands for ______________?

Answer 16

Murashige and Skoog Salt and Vitamin Mixture (1) is a complete medium for plant tissue culture which contains both basal salts and essential vitamins in a premixed format for convenience and time savings.

Question 17

What are the advantages/disadvantages of low/high agar concentration in MP?

Answer 17

The lowest concentration of agar that will sup-port the explants is best, which is about 0.5 to 0.6 per-cent, a level that allows good contact between explant and medium.

Question 18

What are some agar substitutes?

Answer 18

1. Gelrite (also called gellan gum and phytogel) is a polysaccharide derived from Pseudomonas bacteria.
2. Liquid. Nutrient solutions without agar have an advantage for some plants, but some type of support is required to keep explants and cultures from sinking, or a shaker or rotating drum must be used to provide aeration