Monday, April 11, 2011

Two Better 2011 Hulthemias

The two Hulthemia seedlings that I will highlight in this post are more interesting to me than the previous two seedlings that I have been writing about.  These two, exhibit very good blotches despite this being their first blooms.  As mentioned earlier, with maturity blotches increase both in size and in intensity

The first one, code name "O225" appears to be a smaller shrub type.  It's pollen parent is one of my favorite earlier Hulthemias carrying the code name "M62-1".  It was one of the best Hulthemias that germinated in 2009.  Unfortunately, it has very low fertility, therefore I was quite pleased to get a few hips from crosses done with it last year (most of the crosses failed).  The seed parent was 'Pearl Sanford'.  This new seedling shows more evidence that when a repeat blooming (presumably tetraploid) Hulthemia that has an excellent blotch (presumably having more than one copy of the blotch gene(s)), is crossed with a non-Hulthemia, it is still possible to get a good blotch.

As seen in this seedling, I prefer Hulthemias that have a lighter area around the blotch because it sets off the blotch very nicely.  It is harder to appreciate the blotch in seedlings that do not do this - as will be seen in the next seedling.

The next seedling is very unusual, and it appears to be a micromini.  This is the first time that I have had such a small Hulthemia seedling showing such a dark blotch on it's first bloom.  It comes from a complex line, where the seed parent has 'Persian Sunset' in it's background, while the specific pollen parent is unknown (I used mixed pollen from seedlings coming from a cross of 'Cal Poly' X "L83-4").  L83-4 is a cream colored Hulthemia having a fairly larger purple/red blotch.

In the above photo, it is difficult to appreciate the size of the blotch, or even the size of the seedling bloom.  The blotch is even more difficult to appreciate due to the color of the anthers.  They are unusual in that they are a deep red.  For that reason, in the following photo, I removed the anthers and used a centimeter measuring stick to provide better clarity.

As you can see, the bloom is very small, and with the anthers removed, it is much easier to appreciate the blotch.

To be complete, I also removed the anthers from the first seedling and present a photo of it below:

Not knowing whether either of these will be fertile, I have collected the anthers of both and will use their mixed pollen in crosses onto some of my Hulthemia seed parents over the next two days.  I have learned from experience that many of the Hulthemias with the best blotches seem to have lower fertility - that is why I like to mix their pollen.  Curiously, although the bloom size difference between these two seedlings is quite large, the anthers appear to be approximately the same size.


  1. WOW!!! Red anthers!!! These are awesome!!! You have HUGE fingers LOL

  2. Jim, these are really great. You might look into what is known about flower development if you want to think more deeply on the anther size/color question. Elliot Meyerowitz and others have described for Arabidopsis, a weed, how the formation of sepals, petals, stamens and pistels is regulated by a set of genes that turn on at certain times and places. With fivefold symmetry, roses will be different from the 4-fold of the weedy brassicas, but the principles are likely to be the same. It looks like you've somehow gotten the color-forming genes turned on in pollen, as happens in some roses like Captain Thomas, but now apparently under control of the blotch gene whatever that is. Keep up the good work. This may really help us understand how flower coloring in roses is controlled.