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Welcome to the April 2002 edition of my web site! The roses I write about are the Old Garden Roses and select shrub and miniature roses. For tips on rose culture, pruning, propagation and history, see "Other resources on this site". To return to this page, click on the "thorn icon" in the margin at left. Articles from the previous months are archived and can be viewed by clicking on the listings in the left margin. Oh, and please don't write to me for a catalog or pricelist.....this is an information site only.....not a commercial nursery. If you wish to buy roses, see my sponsor, The Uncommon Rose. Thanks!
Well, it has finally happened! Transgenic (gene transfer) technology has rewarded us at last with the first true Blue Roses! For many years now we have heard stories about a handful of companies who have been working at producing the first true Blue Rose, but the results seemed ever elusive. The future is finally here, and rose growers everywhere will rejoice over this new marvel of biotechnology. At Right; 'Fausse Beauté' (Floribunda), one of the newest breed of genetically engineered Blue Roses. The scientists in Florigene (Calgene Pacific) have been working on the development of the transgenic Blue Rose for several years. They transferred the "flavonoid 3', 5'- hydroxylase" gene from petunia to the hybrid tea rose (Rosa x hybrida) to help the rose synthesize delphinidin. Florigene is an Australian Company that has been hard at work on creating the Blue Rose. However, the varieties you see illustrated here are actually from a French research firm called Floraux Marbres. They have previously been working within the realm of traditional plant genetics (breeding), but decided to join the Transgenic race to creat the first Blue Rose. It seems they have in fact won that race, with the anticipated introduction of three marvellous Blue Roses.
At left; A pale blue Hybrid Tea type, called 'Détresse Bleu' . 'Détresse Bleu' is one of two successful Hybrid Teas being introduced by Floraux Marbres, and is sure to be a huge success with Rosarians when they see it. Beautiful Morning Glory blue blooms about 5 inches across are produced freely on this 5 foot tall plant. It is quite upright, as are many Hybrid Teas, but has excellent glossy foliage which is disease free. How could anyone resist such a soft color as this? Notice the white reverse to the petals? What a magnificent rose! Plant gene transfer methods Here is a brief description of the science behind the creation of trangenic Blue Roses; To introduce foreign genes into a plant using two types of transformation method: (A) Agrobacterium - mediated : Agrobacterium tumefaciens and Agrobacterium rhizogenes are soil-borne, bacterial plant pathogens. These soil bacterium infect the plant and transfer several of its genes to the infected plant cells, resulting in high rate of plant cell division and the gall formation. This naturally occuring gene transfer system has been exploited by scientists who have disarmed the Agrobacterium by deleting their tumorigenic genes and engineered them. These Agrobacterium become widely used safe vectors for plant transformation.
(B) Uptake of naked DNA : Including electroporation, PEG-meduated and particle gun methods. The petunia "blue gene" was cloned into a binary plasmid vector, then introduced into the Agrobacterium tumefaciens strain. The co-cultivation of the "blue gene" containing Agrobacterium strain with a rose explant bringing the "blue gene" into the rose genome. The regenerating explants were cultured in the presence of a selectable marker (the select marker gene can be an antibiotic or herbicide resistance gene which was co-transferred with the "blue gene". The transgenic cells, shoots and rooted-shoots are selected. All very interesting, certainly, but its not the methods we, as gardeners, care about.....it's the results! The most wonderful of these three new roses, to my eye, is the last one illustrated here, called 'Incrédulité'. I am a fan of deep, rich colors, and this one is my favorite by far. Buds start out a deep azure blue and when half open, they begin to take on a more purplish cast. It remains blue throughout the bloom life, but has a decidedly warm blue color when fully open. I especially like the muted, dusty blue tones of this one. This is the most fragrant of the three, but alas, it too has only a light scent. Perhaps in future generations, the fragrance can be bred back into the Blue Roses. Florales Merveilles is now working with these varieties as seed and pollen parents to create new generations of blues in the old fashioned way; from seed. They say that the blue coloring is inherited about 25% of the time in the offspring, so with luck, great improvements will be coming down the line. But for now, we can be satisfied with these three marvellous new roses from Floraux Marbres. Appréciez
vos roses! ....and before you give this whole Blue Rose thing one more thought, this page was an April Fools day joke, nothing more. There are no Blue Roses!
There
have been |
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The
First Blue Roses!
The
first of these roses is the one you see illustrated at top right, called
'Fausse Beauté', a Floribunda. It is a double marvel because
not only is it a lovely medium Delphinium blue, but it is also a picotee
blue-on-white! Apparently it is a compact shrub about 2.5 feet tall,
with 3 inch semi-double blooms. They say that there is very little fragrance
to these new roses, as the blue gene has for some reason disrupted the
genes for fragrance that these varieties had before their transformation.
Also, rebloom is not quite as fast as they had hoped for, but that is
a small comprimise when you get such magnificent colors as these!
At
right: 'Incrédulité'