4.4 Are micropropagated plants genetically identical and stable?

Explain the conventional way to prove the true-to-type nature of a clonal plant.

Several researches which examine clonal fidelity use the same two approaches: ISSR (inter simple sequence repeat) and RAPD (Random Amplification of Polymorphic DNA) (Alizadeh & Singh, 2009; Rawat, Rawat, Mehrotra, Chandra, & Nautiyal, 2013; Yadav, Aggarwal, & Singh, 2013). Therefore I consider these two methods as the common way to examine this issue.

For which reasons is mass propagation of Gloriosa such a promising technique and genetic fidelity so important?

Gloriosa is an old medicine plant which has been used for a long time in both Africa and Asia. The plant contains an alkaloid called colchicine. This substance is able to inhibit mitosis and is used to treat acute gout (Bajaj, 2012). Gloriosa is more and more used to produce colchicine through mass propagation (Yadav et al., 2013). Since it is used for medication it is important that the substances of content of the plant stay the same.

Explain the terms somaclonal variants, PCR, Primer, amplification, genetic markers. 

 

Somaclonal variants

Somaclonal variants are new genetic different cells which appear randomly when cells reproduce themselves. This happens particularly when the cells are in vitro clonal propagated.(Jaligot et al., 2011)  

PCR

Polymerase Chain Reaction (PCR) is a method to copy pieces of DNA. That for the DNA is heated to separate the twin strings. Then it is blended with synthetic primers which attach to certain areas of the single strings. Then enzymes extend the starters until there is another double string. (Duran, 2000)

Primer

A Primer is a short piece of single stringed DNA which attaches to a certain area of a single string of DNA. It is the starting point for the DNA polymerase to build the second string.(‘Primer, Starter | Biologie-Definitionen online’, 2013)

Amplification

Amplification means the multiplication of DNA fragments by artificial copying (‘DNA amplification’, 2003).

Genetic Marker

A sequence of DNA which is located on a known place of the chromosome (National Institutes of Health, n.d.).

Is the proposed method save enough to prove genetic fidelity of clonal propagated plants?

Yadav et al. (2013) confirm, that these ISSR and RAPD are convenient to prove genetic stability of mass propagated Gloriosa. As in so many studies (see question 1) these are the preferred methods to prove genetic fidelity, I assume that they are save enough.

Literature:

Alizadeh, M., & Singh, S. K. (2009). Molecular assessment of clonal fidelity in micropropagated grape (Vitis spp.) rootstock genotypes using RAPD and ISSR markers. Iranian Journal of Biotechnology, 7(1), 37–44.

Bajaj, Y. P. S. (2012). Medicinal and Aromatic Plants II. Springer Berlin Heidelberg. Retrieved from https://books.google.ch/books?id=kofuCAAAQBAJ

DNA amplification. (2003). Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health. Retrieved from http://medical-dictionary.thefreedictionary.com/DNA+amplification

Duran, E. A. (2000, April 1). Wissenschaft im Alltag: Die Polymerase-Kettenreaktion. Retrieved 11 March 2017, from http://www.spektrum.de/magazin/wissenschaft-im-alltag-die-polymerase-kettenreaktion/826243

Jaligot, E., Adler, S., Debladis, É., Beulé, T., Richaud, F., Ilbert, P., … Rival, A. (2011). Epigenetic imbalance and the floral developmental abnormality of the in vitro-regenerated oil palm Elaeis guineensis. Annals of Botany, 108(8), 1453–1462. https://doi.org/10.1093/aob/mcq266

National Institutes of Health. (n.d.). Talking Glossary of Genetic Terms. Retrieved from https://www.genome.gov/glossary/index.cfm?id=86

Primer, Starter | Biologie-Definitionen online. (2013, March 17). Retrieved 11 March 2017, from http://www.biologie-lexikon.de/lexikon/primer.php

Rawat, J. M., Rawat, B., Mehrotra, S., Chandra, A., & Nautiyal, S. (2013). ISSR and RAPD based evaluation of genetic fidelity and active ingredient analysis of regenerated plants of Picrorhiza kurroa. Acta Physiologiae Plantarum, 35(6), 1797–1805. https://doi.org/10.1007/s11738-013-1217-x

Yadav, K., Aggarwal, A., & Singh, N. (2013). Evaluation of genetic fidelity among micropropagated plants of Gloriosa superba L. using DNA-based markers — a potential medicinal plant. Fitoterapia, 89, 265–270. https://doi.org/10.1016/j.fitote.2013.06.009