Since the last year the world of adenium in the country, a little excited by the appearance of black adenium flowers. It is said that some of the breeders are keen to multiply and peddle in nurseri and exhibition. Consumers jumped.
And according to my notes, there are several names of Adenium flower variants that are identified with the black adenium, such as Breeders (India), Apolo (Taiwan), from Indonesia appear names such as Gothic, Red Jardine, Sun Red, and Ma Baker.
Comments of adenium hobbyists and experts in the country also varied in response to the appearance of the black flowers. But generally there is a tone of disappointment implied in it. Let's look at the comment for a moment: Honey, the black character is unstable. It's not really black, but "black red". That is the derivative of "black ruby". Incomplete mutations, because black still changes to red. Be careful there are black flower fakes, etc., and so on ...
Yesterday, there were friends from Medan asking me for comments about the phenomenon of black adenium in Indonesia. Even though I know that this friend is actually a "master" of Adenium in Indonesia (and surely he already has the answer), I tried to dare to comment. With the hope of criticism and suggestions from him, from adenium experts in Indonesia, as well as fellow adenium lovers. In order to add and expand my knowledge of adenium, that is certain.
There are no black flowers
Throughout my knowledge and memory, to date there are no black flowers in this world. What about the black orchid Pandurata, or black chrysanthemum flower country? They are still not black flowers, even though there is a black impression. Likewise the existence of the black flowering adenium mentioned above, they are not black.
Again, there is no black interest in this world. Why is that ? Because there is no known black pigment in plant cells. Then why does the black color appear on the flower?
Flower color and pigment
The color of the flower that is observed by the eye, is determined by the color combination of the pigment contained in the flower cell. Both the pigments found in vacuola (cell cavity containing water / plant sap) and in the cell fluid or plastid of flower cells.
There are more than 50 kinds of pigments with each color known to plants, which are then generally grouped into three major groups of pigments, namely anthocyanin, carotene, and chloropil.
Anthocyanin is responsible for the color pink to violet, found in vacuola flowers, soluble in water or plant sap ("sap"), sensitive to the effect of the acidity of flower cells. Examples of this group of pigments are flavonols (yellow - pink), pelargonidin (red), delpinidin (blue), and cianidin (red purple).
Kerotene giving yellow to orange color, found in chromoplas in the cell palstid, soluble in fat, not sensitive to cell acidity.
Chloropil giving green color, found in chloroplasts in cell plastids whose main function is for the photosynthesis of plants.
From the row of color pigments mentioned above, there is no black pigment found on the flower. Then what about the black impression that appears on Adenium? Where did it come from? Mutasikah?
Pigment intensity and black impression
Have we ever observed the color of brown chocolate candy once? Because it's too brown, the chocolate candy gets to our eyes to look like black. Or there are several other objects which are purple and purple. Very blue blue. Because it's too and too purple, too blue gives a black appearance to our eyes. This happens because our eyes are indeed very weak in terms of color separation.
Why is there really brown chocolate? Intensity, answer. So the point is, the intensity of color affects the final appearance of the color of the object, coupled with the weakness of our eyes to color separation.
Speaking of intensity, means talking about a comparison between something with something else. For example, the amount of anthocyanin pigment (in micro grams) compared to the volume of vacuola where the pigment is located, will determine the amount of pigment intensity. The more presence of the pigment or the smaller the volume of vacuole, the more intense the pigment at that place (pigment intensity = the amount of pigment / vacuole volume).
Similarly black adenium and other black flowers in the world. Thus the intensity of the anthocyanin color pigment (in red color) and the pigment co on the petal flower, the flower will appear blackish, or black.
Based on the results of Markham et al's research on blackish Lisianthius nigrescens flowers, this was apparently caused by the high intensity of anthocyanin pigments in vacuola flower cells. Anthocyanin pigments reach 24% of the total dry weight of petal flowers (Kenneth R. Markham et al., Black Flower Coloration in Wild Lisianthius nigrescens: Its Chemistry and Ecological Consequences, New Zealand Institute for Industrial Research and Development).
Another example is the leaves of plants. Chloropil gives green leaves to the leaves, the process of formation is influenced by sunlight. The more sunlight is received, the more chloropyl is formed. This means that the greater the intensity of chloropil, and the more green the color of the leaf. Compared to the color of pale green leaves on plants that are rarely exposed to sunlight.
Vacuola cells and fading of flower color
The small volume of vacuola cells is affected by turgor pressure (the sun is a factor that influences turgor pressure). Vacuole volume is also determined by the growth and development of flower petal cells. With vacuola getting bigger, it means reducing the intensity of anthocyanins in that place. Not to mention the magnification of vacuola occurs due to the entry of water / sap into it. Meanwhile, anthocyanins are known to dissolve in water / sap, so the event will certainly make the pigment intensity decrease. And the flowers appear to fade.
The above event explains why generally the color of the flower appears sharp at the beginning of the blossom, as well as the impression of black on black adenium also clearly visible at the beginning of the flower bloom. But in line with the age of the flower and after all this time exposed to sunlight, the color of the flower will paled or fade. Likewise the presence of black adenium.
Black adenium requirements
In order for flowers to have the impression of black, flowers must have a group of purplish red anthocyanin pigments. The acidity level (ph) of flower cells affects anthocyanins. The more acidic, anthocyanin biosynthesis produces a bright red color, while the more alkaline anthocyanins are produced in dark red (red purple to violet). If this anthocyanin is found in great intensity at Adenium flower vacuola cells, the impression of hitampun color will easily be obtained
Pigment intensity and flower genetics
Viewed from a genetic perspective, the addition of color pigment intensity is determined by the action of the aditip gene. The intensity of the color will be determined by the amount of presence of the color enhancing agent in the genotype which will then be expressed in the phenotype. The inheritance mechanism of adding color takes place both in the locus and between the loci, in addition to the influence of the alela dominance factor at each locus ... sorry to be a little complicated. But sometimes life is not easy, a little complicated and must be familiarized with that condition.
In short, for example the presence or intensity of anthocyanins is controlled by three loci, R1, R2, R3, it may be that red flowers have genotypes R1r1, r2r2, r3r3, purplish red flowers (dark red) having genotypes R1r1, R2r2, r3r2, and black impression flowers have genotypes R1R1, R2r2, r3r3. What will happen if the flower genotype is R1R2, R2R2, R3R3, what are we waiting for? Maybe among colleagues there are those who immediately get it.
Which is the blackest
Of the adenium variants identified with black adenium, it seems to me that Adenium, named Gothic (from Botanica Garden, Jogjakarta) ranks first. Both seen from the percentage of black impression, and from the black color resistance. Why is that ? Gothic has an extraordinary anthocyanin pigment intensity compared to other black adenium variants. And has the pH or acidity level of the flower cell that is most suitable to get the impression of black.
Considering that the color intensity is determined by the action of the additive gene, it seems to me that Gothic is also the best choice of breeders in the effort to bring black adenium, compared to other flowers. Achievement of flower genotype R1R1, R2R2, R3R3 will be faster, but unfortunately the price of grafting is still expensive
Conclusion
There is no black pigment in the flower cell, therefore there is no black flower in this nature. There is a flower with a black impression
The impression of black appears as a result of the high intensity of anthocyanin pigments and the effect of acidity of flower cells.
The pigment intensity is determined by the volume of vacuola flower cells where the pigment is located. Meanwhile the volume of vacuola flower cells is influenced by turgor pressure and the growth phase and development of the flower cell.
The inheritance mechanism of the addition of the flower color pigment intensity is influenced by the action of the aditip gene, in addition to the influence of alela dominance at each locus.
Gothic (product Botanica Garden, Jogjakarta) is the most impressive black adenium flower variant compared to others, such as Breeder, Apolo, Sun Red, Red Jardine, or Ma Baker.
I think Gothic is the parent who is the closest to being able to get more black adenium (get the adenium R1R1, R2R2, R3R3 genotypes that are the ideal).