Sunday, December 16, 2012

Can we make a species better?

Codonanthe devosiana (formerly digna)

Story # 79,
      Can we make a species better than it already is?  Is it possible to improve on a species that has survived for untold millions of years in the wild?

      I learned the original definition of a botanical ‘species’ as a plant found in nature that is uniform in it’s characteristics and comes true (identical to the parent) when self-pollinated.

      So if they are all identical then how can they be improved?  It seems that the modern day definition is not as rigid and some species are variable and in some cases can have different colored flowering forms within the species.

      The plant that I want to improve is Codonanthe digna, a small trailing plant with small bell shaped white flowers and orange berries. (The name was carnosa, then digna.  It may now be devosiana).  Well grown plants will self-branch and get a flower at every leaf axil.  It could be a commercial plant in the terrarium market if crop time could be speeded up.

      My proposal is to grow quantities of seed crops of Codonanthe and select for speed and flower size.  In every measurable step, we select the best.  Save the first to germinate and from them, the first to flower.  If flower size improves, of course, save them.  Record the times so we can see if any improvement is made in successive generations.

      Does science support this plan?  I think so.  Plants have been improved by intercrossing species within a Genius.  This is self-pollinating a species and hope for variability. In nature seed germinates at varying rates to insure survivability, so we will just select the fastest.

      Since no one has tried to improve Codonanthe digna, the story is not yet written.  But nothing can be lost in trying since all plants, fast or slow, can be sold.  If somehow flower size improves then all the observation will pay off.

      There is a pink flowered form of Codonanthe from Brazil that we are attempting to establish.  The goal there will be to select for the brightest pink.  Then cross the white with the pink and see if we get hybrid vigor and a big, bright, pink flower on a tough little trailing plant.  But that’s a different story.

Codonanthe devosiana- Pink form (formerly digna)
This story was first published in the Delaware African Violet and Gesneriad Society newsletter and then shown in Gleanings.


  1. Cool project. I'd be interested in helping out. Have you thought of mutagenesis as a way of speeding things up?

  2. Carol,
    Thank you for your interest in my Codonanthe project.
    I am not sure what you have in mind with mutagenesis?
    I am not attempting to cause a Codonanthe species to mutate, either to cause a polyploidy version or just to get something randomly different. My plan is simply to select horticulturally better clones through successive generations.
    There have been two other comments that will be shown in a future blog.
    You may e-mail me directly at