Tissue Culture Stages

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Explanting- Stage I
get plant material in sterile culture so it survives
provide with nutritional and light needs for growth

Stage II
rapid multiplication
stabilized culture
goal for a commercial lab
difficult and time consuming to maintain.

Rooting - Stage III

may occur in Stage II
usually induced by changes in hormonal environment
lower cytokinin concentration and increase auxin ROOTING may skip stage III and root in a greenhouse

Stage IV
transplantation and aftercare
usually done in greenhouse
keep RH high (relative humidity),gradually increase light intensity and lower RH after rooting occurs
allows plants to harden and helps plants form cuticle

Types of PLANT TISSUE CULTURE

Seed culture
Ovary or ovule culture
Embryo culture
Anther and microspore culture
Shoot apical meristem culture
Somatic embryogenesis
Organogenesis
Callus Cultures


Seed culture

Increasing efficiency of germination of seeds that are difficult to germinate in vivo
Precocious germination by application of plant growth regulators
Production of clean seedlings for explants or meristem culture


Ovary or ovule culture

Production of haploid plants
A common explant for the initiation of somatic embryogenic cultures
Overcoming abortion of embryos of wide hybrids at very early stages of development due to incompatibility barriers
In vitro fertilization for the production of distant hybrids avoiding style and stigmatic incompatibility that inhibits pollen germination and pollen tube growth

Embryo culture

Overcoming embryo abortion due to incompatibility barriers
Overcoming seed dormancy and self-sterility of seeds
Embryo rescue in distant (interspecific or intergeneric) hybridization where endosperm development is poor
Shortening of breeding cycle

Anther and microspore culture

Production of haploid plants
Production of homozygous diploid lines through chromosome doubling, thus reducing the time required to produce inbred lines
Uncovering mutations or recessive phenotypes


Shoot apical meristem culture

Production of virus free germplasm
Mass production of desirable genotypes
Facilitation of exchange between locations (production of clean material)
Cryopreservation (cold storage) or in vitro conservation of germplasm

Somatic embryogenesis

One major path of regeneration
Mass multiplication
Production of artificial seeds
As source material for embryogenic protoplasts
Amenable to mechanization and for bioreactors

Organogenesis

One major path of regeneration
Mass multiplication
Conservation of germplasm at either normal or sub-zero temperatures

Callus Cultures

In some instances it is necessary to go through a callus phase prior to regeneration via somatic embryogenesis or organogenesis
For generation of useful somaclonal variants (genetic or epigenetic)
As a source of protoplasts and suspension cultures
For production of metabolites
Used in in vitro selection