генетика пшеницы и выводы
Итак, что же в итоге?..
Первое. С точки зрения обеспечения пищевыми ресурсами, переход древних охотников и собирателей к земледелию является крайне невыгодным, но они все-таки совершают его.
Второе. Земледелие зарождается именно в наиболее изобильных регионах, где полностью отсутствуют какие-либо естественные предпосылки для отказа от охоты и собирательства.
Третье. Переход к земледелию осуществляется в зерновом, самом трудоемком его варианте.
Четвертое. Очаги древнего земледелия территориально разделены и сильно ограничены. Различие культивируемых в них растений указывает на полную независимость этих очагов друг от друга.
Пятое. Сортовое разнообразие некоторых из основных зерновых культур обнаруживается на самых ранних стадиях земледелия при отсутствии каких-либо следов "промежуточной" селекции.
Шестое. Древние очаги возделывания целого ряда культурных растительных форм почему-то оказались географически удалены от мест локализации их "диких" сородичей.
тут правда есть возражение, к последнему: развели "хорошую" и истребили дикую за ненадобностью...
но на самом деле в заповедниках она бы осталась, в то время как там её нет
ну так а выводы какие?
Угадай с трёх раз какие у него могут быть выводы.
Русские - потомки Высшей Расы Инопланетян, которые привезли с собой пшеницу и которую у них потырили евреи и негры?
Негры и индусы в России еще и слонов украли
выводы в ссылке. они забавные. я не полностью разделяю, поэтому и не цитирую.
Genetics and breeding
Wheat genetics is more complicated than that of most other domesticated species. Wheat is capable of forming stable polyploidy, or having more than two sets of chromosomes (diploid). For example, common bread wheat (T. aestivum) is hexaploid. A further complicating factor is that four out of five of the most common wheat species are the results of hybridization.
Einkorn wheat (T. monococcum) is diploid (2x chromosomes).
Tetraploid wheats (e.g. emmer and durum wheat) derive from wild emmer, T. dicoccoides. Wild emmer is the result of a hybridisation between two diploid wild grasses, T. urartu and a wild goatgrass such as Aegilops searsii or Ae. speltoides. The hybridization that formed wild emmer occurred in the wild, long before domestication.
Hexaploid wheats evolved in farmers' fields. Either emmer or durum wheat hybridized with yet another wild diploid grass (Aegilops tauschii) to make the hexaploid (6x chromosomes) wheats, spelt wheat and bread wheat.
Heterosis or hybrid vigor (as in the familiar F1 hybrids of maize) occurs in common (hexaploid) wheat, but it is difficult to produce seed of hybrid cultivars on a commercial scale as is done with maize because wheat flowers are complete and normally self-pollinate. Therefore commercial hybrid wheat seed is produced using chemical hybridizing agents, plant growth regulators that selectively interfere with pollen development. Hybrid wheat has been grown commercially in Europe (particularly France) since the 1990s. Hybrid wheats (F1) should not be confused with standard wheats bred by making hybrids using hand emasculation and crossing, then inbred for many (ten or more) generations before release as a variety
http://en.wikipedia.org/wiki/Wheat
зы. сам не биолог, поэтому в предмете не разбираюсь.
Wheat genetics is more complicated than that of most other domesticated species. Wheat is capable of forming stable polyploidy, or having more than two sets of chromosomes (diploid). For example, common bread wheat (T. aestivum) is hexaploid. A further complicating factor is that four out of five of the most common wheat species are the results of hybridization.
Einkorn wheat (T. monococcum) is diploid (2x chromosomes).
Tetraploid wheats (e.g. emmer and durum wheat) derive from wild emmer, T. dicoccoides. Wild emmer is the result of a hybridisation between two diploid wild grasses, T. urartu and a wild goatgrass such as Aegilops searsii or Ae. speltoides. The hybridization that formed wild emmer occurred in the wild, long before domestication.
Hexaploid wheats evolved in farmers' fields. Either emmer or durum wheat hybridized with yet another wild diploid grass (Aegilops tauschii) to make the hexaploid (6x chromosomes) wheats, spelt wheat and bread wheat.
Heterosis or hybrid vigor (as in the familiar F1 hybrids of maize) occurs in common (hexaploid) wheat, but it is difficult to produce seed of hybrid cultivars on a commercial scale as is done with maize because wheat flowers are complete and normally self-pollinate. Therefore commercial hybrid wheat seed is produced using chemical hybridizing agents, plant growth regulators that selectively interfere with pollen development. Hybrid wheat has been grown commercially in Europe (particularly France) since the 1990s. Hybrid wheats (F1) should not be confused with standard wheats bred by making hybrids using hand emasculation and crossing, then inbred for many (ten or more) generations before release as a variety
http://en.wikipedia.org/wiki/Wheat
зы. сам не биолог, поэтому в предмете не разбираюсь.
выводы в ссылке. они забавные. я не полностью разделяю, поэтому и не цитирую.ЛОЛ, я угадал по ходу
Пофигист, сними плюсик!
Phylogenetic relationships of Triticum and Aegilops and evidence for the origin of the A, B, and D genomes of common wheat (Triticum aestivum)
Common wheat (Triticum aestivum) has for decades been a textbook example of the evolution of a major crop species by allopolyploidization. Using a sophisticated extension of the PCR technique, we have successfully isolated two single-copy nuclear genes, DMC1 and EF–G, from each of the three genomes found in hexaploid wheat (BAuD) and from the two genomes of the tetraploid progenitor Triticum turgidum (BAu). By subjecting these sequences to phylogenetic analysis together with sequences from representatives of all the diploid Triticeae genera we are able for the first time to provide simultaneous and strongly supported evidence for the D genome being derived from Aegilops tauschii, the Au genome being derived from Triticum urartu, and the hitherto enigmatic B genome being derived from Aegilops speltoides. Previous problems of identifying the B genome donor may be associated with a higher diversification rate of the B genome compared to the Au genome in the polyploid wheats. The phylogenetic hypothesis further suggests that neither Triticum, Aegilops, nor Triticum plus Aegilops are monophyletic.
Common wheat (Triticum aestivum) has for decades been a textbook example of the evolution of a major crop species by allopolyploidization. Using a sophisticated extension of the PCR technique, we have successfully isolated two single-copy nuclear genes, DMC1 and EF–G, from each of the three genomes found in hexaploid wheat (BAuD) and from the two genomes of the tetraploid progenitor Triticum turgidum (BAu). By subjecting these sequences to phylogenetic analysis together with sequences from representatives of all the diploid Triticeae genera we are able for the first time to provide simultaneous and strongly supported evidence for the D genome being derived from Aegilops tauschii, the Au genome being derived from Triticum urartu, and the hitherto enigmatic B genome being derived from Aegilops speltoides. Previous problems of identifying the B genome donor may be associated with a higher diversification rate of the B genome compared to the Au genome in the polyploid wheats. The phylogenetic hypothesis further suggests that neither Triticum, Aegilops, nor Triticum plus Aegilops are monophyletic.
хорошо забытое старое --- это во многом новое 
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Irina_Afanaseva
ни за что бы не подумал, что это интересная тема, пока не прочёлполный текст с картинками на
http://piramyd.express.ru/disput/sklyarov/ZERNO/zerno.htm