Plant tissue culture is the growth of plant cells, tissues or organs under controlled, aseptic conditions on a defined nutrient medium. In commercial horticulture, one of its most important applications is micropropagation: producing large numbers of plants from relatively small amounts of starting material.
Why plants can be cultured in vitro
Plant cells retain remarkable developmental plasticity. Under appropriate conditions, cultured tissues can form shoots, roots, callus or embryos. The response depends on genotype, tissue type, developmental state, medium composition and the balance of plant growth regulators.
Stage 1: establishment
Selected explants are cleaned and surface-disinfested before introduction to sterile medium. Establishment is one of the most challenging stages because microorganisms living on or within plant material can proliferate rapidly in nutrient-rich culture media.
Stage 2: multiplication
Established cultures can be encouraged to produce multiple shoots. Cytokinins are commonly used to promote shoot proliferation, although the appropriate compound and concentration vary considerably among taxa and protocols.
Stage 3: rooting and elongation
Shoots may be transferred to conditions that favour elongation and root formation. Auxins are frequently involved in rooting responses. Some species root readily without a separate in-vitro rooting stage, while others benefit from a dedicated treatment.
Stage 4: acclimation
Plants produced in vitro develop under conditions very different from a greenhouse or home. Humidity is high, light levels can be relatively low, sugar may be supplied by the medium, and gas exchange is constrained by the culture vessel. Plantlets therefore require a transition period after removal from culture.
Why contamination matters
Bacteria and fungi can rapidly outgrow plant material on nutrient media. Aseptic technique, sterilised equipment, appropriate vessel handling and careful explant preparation are therefore fundamental to tissue-culture production.
Does tissue culture create mutations?
Tissue culture does not automatically make plants genetically unstable. However, genetic or epigenetic variation can arise during culture, particularly in systems involving prolonged callus phases, strong selection pressure or extensive subculture. This phenomenon is commonly discussed under the term somaclonal variation.
Why commercial growers use micropropagation
Micropropagation can provide rapid multiplication, efficient use of space, year-round production and distribution of large numbers of uniform propagules. Its value depends on the crop: labour, contamination losses, multiplication rate and acclimation success all influence the economics.
Continue learning
Read our tissue culture acclimation guide and our explanation of auxin and cytokinin in propagation.
Plant tissue culture services and wholesale supply
JungleBotanics is developing UK plant tissue culture services for suitable rare and ornamental plants. If you have material you want assessed for micropropagation, see our Plant Tissue Culture Services UK page. Plant retailers, nurseries and professional growers looking for bulk future availability can register through Wholesale Tissue Culture Plants UK.