In vitro conservation and cryopreservation of medicinal and aromatic plants : a review

الملخص EN

Medicinal and aromatic plants are those containing special chemical components that enable them to relief pain, release pleasant aromas, and improve food flavors.

Meanwhile, medicinal and aromatic plants are under real jeopardy due to the uncontrolled collection of these plants as a result of being extensively used in herbal medicine and food industry.

So conservation action for these natural resources is of high priority.

Plants conserved under in situ conservation conditions are exposed to natural disasters, pests and pathogens in addition to the fluctuating government policies.

Also ex situ conservation is very difficult to be applied as adequate samples have to be collected for the conservation of genetic diversity.

In vitro conservation is offering a strong and a multi package of techniques that do so good when other conservation methods are not feasible.

Slow growth conservation is a very simple in vitro technique based on reducing the growth rates of the tissue cultured plant for short or mid-term storage and yet increasing the intervals between subcultures.

In this conservation type, several techniques are used separately or in combinations to slow down the growth rate of the stored explants, such as, addition of elevated levels of osmotic agents or ABA in addition to storage under minimal growth conditions such as low temperature and dark incubation.

Cryopreservation is another conservation technique that is usually described as the most reliable tool for long-term storage of plant germplasm and reported to be advantageous over most other conservation methods in terms of simplicity, applicability to a wide range of genotypes and ability to maintain the genetic stability of plant material.

Thanks to the use of cryopreservation techniques, such as, encapsulation-dehydration, vitrification, encapsulation-vitrification, and droplet-vitrification, many medicinal plant species are conserved indefinitely for the next generations.