Tissue Culture and Orchid

Question 1

The last stage of micropropagation in which the delicate new plant must be kept in an environment with high humidity and protection from pathogens

Answer 1

Acclimatization

Question 2

A shoot that forms in tissue culture from parenchyma cells in tissue that may or may not be shoot tissue

Answer 2

Adventitious shoot

Question 3

A substance used to create a semi-solid (rather than liquid) growth medium in tissue culture

Answer 3

Agar

Question 4

A heavy growth medium made from expanded clay that never decomposes and provides good aeration; often used for orchids

Answer 4

Aliflor

Question 5

Free from bacteria and other contaminating pathogens

Answer 5

Aseptic

Question 6

A shoot that forms in tissue culture from a new bud formed during the micropropagation process

Answer 6

Axillary shoot

Question 7

Older, leafless pseudobulbs

Answer 7

Backbulb

Question 8

A method by which a plant with a mutation in only one or two histogenic layers can be grown in tissue culture and stabilized such that the mutation is in all three histogenic layers of the new plant(s)

Answer 8

Chimera resolution

Question 9

The first stage of micropropagation in which small, branched plantlets form on media that usually does not contain any growth regulators

Answer 9

Establishment

Question 10

A section of plant tissue from which new plants are propagated in tissue culture

Answer 10

Explant

Question 11

The name used to refer to a particular interspecific cross in the scientific name of an orchid

Answer 11

Grex

Question 12

Term applied to plant hormones, especially when referring to plant hormones that are synthetically produced and used in tissue culture

Answer 12

Growth regulator

Question 13

Phrase literally meaning “in the glass” often used to refer to tissue culture

Answer 13

In vitro

Question 14

Aerial orchid plantlet

Answer 14

Keiki (pronounced kay-key)

Question 15

A piece of equipment used in tissue culture labs to maintain a sterile work area through the use of a series of air filters

Answer 15

Laminar flow hood

Question 16

Development of new plants in artificial medium under aseptic conditions from very small portions of plants; can be an asexual or sexual form of plant propagation

Answer 16

Micropropagation

Question 17

A term for a growth form in orchids in which there is only one main stem arising directly from the roots

Answer 17

Monopodial

Question 18

The stage of micropropagation in which plantlets are cut apart and placed on new media with a high cytokinin:auxin ratio so that new axillary or adventitious shoots can form

Answer 18

Multiplication

Question 19

A plant with multiple copies of its DNA in each cell (3 or more)

Answer 19

Polyploid

Question 20

The stage of micropropagation in which new plantlets form roots prior to being removed from the tissue culture environment

Answer 20

Pretransplant

Question 21

Stem tissue of sympodial orchids used as food and water storage

Answer 21

Pseudobulb

Question 22

A term for a growth form in orchids in which multiple pseudobulbs branch off an underground stem (rhizome) that arises from the roots

Answer 22

Sympodial

Question 23

Another term used to describe micropropagation but also used to refer to other applications besides propagation for growing new plantlets in an in vitro environment

Answer 23

Tissue culture

Question 24

Why is it impractical to try to sexual propagate orchids at home?

Answer 24

In nature seed germination requires mycorrhizal fungi for food and some water uptake. Orchid seeds do not have ability to create their own food.

Without the fungi tissue culture is the only way to make sure they get enough food to germinate. Successful micropropagation requires special equipment and skills which the typical home gardener does not have.