Tissue Culture and Orchid Flashcards
The last stage of micropropagation in which the delicate new plant must be kept in an environment with high humidity and protection from pathogens
Acclimatization
A shoot that forms in tissue culture from parenchyma cells in tissue that may or may not be shoot tissue
Adventitious shoot
A substance used to create a semi-solid (rather than liquid) growth medium in tissue culture
Agar
A heavy growth medium made from expanded clay that never decomposes and provides good aeration; often used for orchids
Aliflor
Free from bacteria and other contaminating pathogens
Aseptic
A shoot that forms in tissue culture from a new bud formed during the micropropagation process
Axillary shoot
Older, leafless pseudobulbs
Backbulb
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)
Chimera resolution
The first stage of micropropagation in which small, branched plantlets form on media that usually does not contain any growth regulators
Establishment
A section of plant tissue from which new plants are propagated in tissue culture
Explant
The name used to refer to a particular interspecific cross in the scientific name of an orchid
Grex
Term applied to plant hormones, especially when referring to plant hormones that are synthetically produced and used in tissue culture
Growth regulator
Phrase literally meaning “in the glass” often used to refer to tissue culture
In vitro
Aerial orchid plantlet
Keiki (pronounced kay-key)
A piece of equipment used in tissue culture labs to maintain a sterile work area through the use of a series of air filters
Laminar flow hood
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
Micropropagation
A term for a growth form in orchids in which there is only one main stem arising directly from the roots
Monopodial
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
Multiplication
A plant with multiple copies of its DNA in each cell (3 or more)
Polyploid
The stage of micropropagation in which new plantlets form roots prior to being removed from the tissue culture environment
Pretransplant
Stem tissue of sympodial orchids used as food and water storage
Pseudobulb
A term for a growth form in orchids in which multiple pseudobulbs branch off an underground stem (rhizome) that arises from the roots
Sympodial
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
Tissue culture
Why is it impractical to try to sexual propagate orchids at home?
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.
