Sunday, April 12, 2015

Blog entry week 13 - 15

Botanists versus molecular biologists

It is time to summarize the advantages and disadvantages of these two methods and, what is important – limits of these both methods. My answers:

1. What are the advantages and disadvantages of the classical botanical method to describe plant species?

Advantage definitely is fact, that method is cheap and fast – person with knowledge in botanic always can identify plant in it natural area, in the field without collecting samples, damaging natural area (often we need more than one sample) working in the lab.
Disadvantages. Do not forget that Carl Linnaeus lived 300 years ago and during this time any scientific discipline might change and update itself. For example: Echinacea is the genus, but there are nine different species.
Two of the most popular species of Echinacea are angustifolia and purpurea. The botanical names are Echinacea angustifolia and Echinacea purpurea.

The purpose of assigning botanical names to plants is so that each plant has a single name that’s used worldwide to identify it. Botanical names prevent people from confusing different species of plants, but also indicate that different species are related (Advantages and Disadvantages of Common Names & Botanical Name, https://ehomoeopathy.wordpress.com/2011/10/21/advantages-and-disadvantages-of-common-names-botanical-name/), so it means that we definitely need deep knowledges even to identify sample within genus.

2. What are advantages and disadvantages of barcoding?

Advantages: DNA barcoding is a fast, accurate, and standardized method for species level identification, by using short DNA sequences (Lebonah et al., 2014). DNA barcoding is the standardized research that facilitates biodiversity studies like species identification and discovery. This technique helps researchers to understand genetic and evolutionary relationships by assembling molecular, morphological, and distributional data (Savolainen et al., 2014). Additional advantages of the method would be the possibility of identifying individuals at any stage of development, and the prospect of discriminating between morphologically identical species (DNA barcoding and…, 2010), that is not possible, using classical bothanic.

Disadvantages: On the first view, disadvantages does not exist. But I still think - What about hybrids? Do we have necessary primers for them? And there are possibility of simple human mistake in the lab and – results of identification of exact sample of plant are not reliable anymore, but in orchard you will always recognize necessary sample and not make a mistake (of course, if you have a knowledges).

3. Give an example of plant species where barcoding led to the revision of the description of plant species.

That example is not so easy to find, but there were researches about identification of plant species in honey, also honey quality (Bruni et al., 2014), that is not possible without barcoding.

4. In your opinion, what is the best strategy to do plant taxonomy? Would you rather trust the botanist or the molecular biologist?
 If question is only - would you rather trust the botanist or the molecular biologist, I definitely would trust molecular biologist, because systematic of botanic constantly changes, experts every year discover new and new species and often even biggest experts argue about belonging of exact species or necessary of new species or subspecies. But for reliable plant identification, taxonomy is too early to refuse from taxonomists at all. Even high quality lab and experts can not replace persons, who know plants in the orchards and for the high quality plant taxonomy we need to have synergy, not competition between molecular biology and taxonomists.


Literature:

D. E. Lebonah, A. Dileep, K. Chandrasekhar, S. Sreevani, B. Sreedevi, and J. Pramoda Kumari (2014) DNA Barcoding on Bacteria: A Review. Volume 2014 (2014), Article ID 541787, 9 pages.

V. Savolainen, R. S. Cowan, A. P. Vogler, G. K. Roderick, and R. Lane, “Towards writing the encyclopaedia of life: an introduction to DNA barcoding,” Philosophical Transactions of the Royal Society B: Biological Sciences, vol. 360, no. 1462, pp. 1805–1811, 2005.

DNA barcoding and traditional taxonomy unified through Integrative Taxonomy: a view that challenges the debate questioning both methodologies. In: Biota Neotrop. vol.10 no.2 Campinas Apr./June 2010.

I. Bruni, A. Galimberti, L. Caridi, D. Scaccabarozzi, F. De Mattia, M. Casiraghi, M. Labra (2014) A DNA barcoding approach to identify plant species in multiflower honey. Food Chemistry 170 (2015) 308–315.

5 comments:

  1. Comment by Ruth

    Dear Dmitrijs

    In general, a very great improvement comparing blog no. 2 with blog no. 1! You now used many literatures and wrote down the references. Congratulation!

    Interesting consideration that botanical knowledge increased during the last 300 years as well. Could barcoding therefore be seen just as a part of this development?

    I also like your consideration about the limit of barcoding, while looking at hybrids as well the human mistakes, usually happens in the lab.

    I found it also quite difficult to find an appropriate paper giving an example where barcoding led to the revision of the description of plant species. Nevertheless, your mentioned paper gives a good example of the advantage of barcoding.

    Well done with your opinion about taxonomy. Now we understand, what you think about it.

    Well done! Ruth

    ReplyDelete
  2. Comment by Ruth

    Dear Dmitrijs

    In general, a very great improvement comparing blog no. 2 with blog no. 1! You now used many literatures and wrote down the references. Congratulation!

    Interesting consideration that botanical knowledge increased during the last 300 years as well. Could barcoding therefore be seen just as a part of this development?

    I also like your consideration about the limit of barcoding, while looking at hybrids as well the human mistakes, usually happens in the lab.

    I found it also quite difficult to find an appropriate paper giving an example where barcoding led to the revision of the description of plant species. Nevertheless, your mentioned paper gives a good example of the advantage of barcoding.

    Well done with your opinion about taxonomy. Now we understand, what you think about it.

    Well done! Ruth

    ReplyDelete
  3. Hi Dmitrijs

    Ruth hit the point: you are doing a great job!! And your arguments are surely worth the issue.

    You showed good examples of both sides, and this is great. As I commented to Remo, finding such papers on taxonomic renaming of plant species using molecular data might be difficult to find.

    I really expect your group to go for a great panel discussion!! I can hardly await what proposals you will have for the participants.

    Regards

    Theo

    ReplyDelete
  4. Hey Dmitrijs

    Great job, very proffessional blog entry!

    I don't agree with your last point, to trust the molecular biologist. Maybe i'm wrong but i think if we talk about how taxonomy has to be done we absoluteley must trust the botanist. Taxonomy is not just to differentiate between species (in that case i also would trust the molecular biologist). If we want to establish a new system of taxonomy based on molecular biology, in my opinion we had to analyse the whole genome of every plant and not just a certain gene region. Am i wrong? i'm really wondering what all of you think about that!

    ReplyDelete
    Replies
    1. Hi Remo

      You make life interesting!! I agree with you that barcoding may be inprecise and you would need more data of the genome, but I disagree that the botanist is better in generating a good taxonomy. I have seen enough from bacteriology that even the best classical microbiologist could not distinguish strains that belong to obvious different species, and that some species were put together based on genetic data that were artificially split by biochemical traits. There is surely a huge value in genetic data.

      Your comment is showing me that your group is really ready for the forum discussions. It will be a pleasure to pick the roles for your group.

      Regards

      Theo

      Delete