Preservation of Plant Species: Methods in Plant Biotechnology

Posted by: r00ty
Date: 2018-12-06 11:07

Biodiversity within the kingdom of Plantae is not only important for the ecosystem. It is a source of material for development and enhancement of various crops, a crucial factor for food security and agro-biodiversity. Due to compounds of the secondary metabolism, a wide range of plant species also occupy an eminent position in pharmaceutical applications.

Targeted problems

Maintenance of Biodiversity
To move against the constant loss of biodiversity, ex situ conservation and saving genetic resources of rare and endangered plant species are important steps for its deceleration.

Recalcitrant seeds
Also known as unorthodox seeds, which especially occur in species from tropical origins (e.g. Theobroma cacao or Mangifera ssp.). Embryonic plants in recalcitrant seeds are not able to survive the combination of drying and freezing during ex-situ conservation. Desiccation influences intracellular structures, and uncontrolled metabolism can lead to oxidative damage. Preservation methods should allow bypassing such limitations.

Seedless plants
Musa species like the ‘Cavendish’-Banana and other edible cultivars are not able to produce seeds. Reproduction is only possible by vegetative propagation, nowadays mostly realized by clonal mass micropropagation.

Sterile genotypes
New Biotechnology-derived plant genotypes, e.g. by genome editing, require suitable methods for their conservation to ensure their reproducibility.

Methods

A main factor which determines the selection of a suitable way is time: Short term preservation can be realized using tissue culture techniques, whereas cryopreservation is favorable for long-term projects.

Tissue culture
Maintenance of germplasm using tissue culture techniques allows to achieve disease-free material which can be used for further micropropagation.

A proper selection of the technique is important: Some methods can cause genetic instability which is also known as somaclonal variation. Additionally, the usage of specific reagents like plant growth regulators has been associated with this effect.

Review: Somaclonal variation in plant tissue culture

Due to the genetic instability, basic tissue culture is not considered to be a long-term solution for germplasm maintenance. Some more advanced techniques allow to generate artifical seeds which could be a further option for the storage of germplasm.

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