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CULTIVAR / КУЛЬТИВАР журнал любителей кактусных аномалий ENGLISH / Рус-Win1251 | |||||
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In response we received an objection from another biologist – Nicolay Shemorakov: "There is no unified opinion. It is right to say both Gymnocalycium friedrichii and Gymnocalycium mihanovichii v friedrichii, as well as Gymnocalycium mihanovichii v pirraretaense and Gymnocalycium friedrichii v pirraretaense. They are synonyms. It is "fashionable" now to abolish old classifications and create new ones. But it means nothing yet. For instance, I like (and many cactophiles do) Kurt Bakeberg's classification and I use it. Others prefer Fred Katterman's system. Let them use it. It's quite another matter, as a famous Russian scientist Georgiy Volskiy said: "Don't put foolish ideas into your head. The point is not to become confused and not to confuse others". Each new classification should be approved by the world society and then it will adapt and replace other systems of classification. This process takes time". Here is an opinion spoken out by Dmitriy Rogatskin (Smolensk), expert on Gymnocalycium.
The colored forms of Gymnocalycium referring to subgenera Microsemineum, Pirisemineum and Ovatisemineum are rarely to be found and mentioned. At least, not oftener than any other cacti. The representatives of Macrosemineum (G. denudatum) and Trichomosemineum (G. ragonesii and so on) are better known. Subgenus Muscosemineum is an absolute champion. It turns out that colored forms are more often formed by the oldest from the point of view of evolution subgenus (Macro-) and two youngest (Trichomo- и Musco-). The same subgenera also form crested and monstrous forms most often. At least I watched crested-monstrous G. Mihanovichii and crested G. Riojense appearing in my collection. Not going into detail (it will be interesting only to specialist and Gymnocalycium fans) one can say that there are 2 main branches in subgenus Muscosemineum: mountain Argentine species close to G. schiekendantzii (G. pungens, G. michoga, G. stuckertii and others) and chakoa species close to G. megatae и G. mihanovichii. In the early version of B.Schutz's classification there were a separate section for plants with apical flowers where G. mihanovichii, G. friedrichii, G. damsii and G. Anisitsii were included. Subgenus Muscosemineum is the most detached. It does not have transitional forms to any other subgenus. The 4 mentioned species are considered the youngest and advanced in terms of evolution (which you can't say of the Argentine plants of the subgenus). G. mihanovichii grows in the North-West of Paraguay, on the border of Eastern and Western Chako, within a radius of 100 km around Philadelphia. The natural habitat of G. Friedrichii crosses that of G. Mihanovichii, but mainly is located more to the North, in the Western Chako, in a more severe climate. This place is a rarely inhabited hilly plain with thick bush, hard to get through. It is the hottest spot of the continent in summer. The temperature may rise up to 47 (С. It rains hard for several months successively. Rivers overflow the banks and flood everything around for dozens kilometers. Some plants stay under water for some time. By the autumn the rains stop, and the water starts evaporating. The lowlands turn into salty marshes. In winter drought starts and Western Chako turns into a real semi-desert – leaves fall, grass burns out, rivers and marshes dry up and get covered with salty cracked crust. The pressure rises, the temperature falls (not lower than 10 (С). G. friedrichii and a number of other species live in those extreme conditions. As you probably know, regular exposure of living tissue to different stresses is a mutagen factor leading on one hand to the growth of resistibility, but on the other hand – to lethal mutations lying in the basis of colored forms. If we take into consideration that G. Friedrichii is a young, actively progressing taxon with lots of local forms having a very short period of vegetation in its homeland (spring), characterized by a very quick growth and early maturing tissues, and having, in any conditions, the most stable pigmentation of epidermis, there is nothing to be surprised at. However, this is just a hypothesis. (On the other hand, the species from Chako province form hybrids easily, and the frequency of mutations is higher with hybrids – both cultural and natural. Though it is clear from the described examples that the proportion is equal – three hybrids against three "brend" ones. However, the sample is not large and is unlikely to be significant.) Gert J.A. Neuhuber Dear Mr. Kalishev,
I hope I could help you, mit freundlichen Grьssen, Gert J.A. Neuhuber h.neuhuber@mail.asn-linz.ac.at
Translation Irina Koudina (Okounkova , Mosсow, Russia, e-mail: irinkos2@yandex.ru) Walery Kalishev, Chelyabinsk, Russia, mailto: e-mail |