Principles of Cutting eg. in sugar cane
- a stem with at least one node or bud is cut
- stem then is covered in a thin layer of soil
- new shoots grow from buds and new underground stem (rhizome) is formed
NB some plants may not grow readily as sugar cane so growth hormones are used
cuttings can be taken from stem, root or leaves of plants
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Principles of Tissue culture
- removal of meristematic cells from the plant - these cells are explant
- explant is immersed in well aerated solution containing balance of auxin and cytokinin to stimulate cell growth and division and nutrients (sucrose, and inorganic ions K,Mg and nitrates) and is sterile to prevent fungi and bacteria
- undifferentiated cells in the explants divide by mitosis to produce callus
- callus is placed in agar jelly with nutrients to produce root and shoot
- when plant is large enough it's placed in sterile soil
NB not all plants divide by mitosis but few meristematic cells are found in all plants
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Importance of vegetative reproduction
- new plants are easily established where the seeds are not viable and do not grow
- gives a reliable supply because of uniform appearance
- plants are genetically identical
- plants are uniform size which helps harvesting and packaging
- used to generate large numbers of new, genetically identical plants
