What type of polyploid is Triticum sativum?Biology

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Bread wheat, is a plant that is a polyploid that resulted from human selection. Three different plant species gave rise to modern bread wheat. It contains six sets of chromosomes. Einkorn wheat had a chromosome number of 14 and is considered the ancestral parent of the 28 chromosome emmer wheat. It is believed that Einkorn with 14 chromosomes and a wild grass called Aegilops speltoides,  in Asia, with 14 chromosomes formed a hybrid plant. Originally, 7 chromosomes from each made an F-1 hybrid with 14 chromosomes. Then, if accidental doubling occurred, the hybrid would contain 28 chromsomes--a doubled set. This is believed to explain the emergence of the 28 chromosome Emmer wheat. It is believed the emmer wheat was the ancestor of the 42 chromosome modern bread wheat. If emmer with 28 chromosomes and goat grass, Aegilops squarrosa, a weed in the Mediterranean area with 14 chromosomes, hybridized, and then subsequently doubled, modern bread wheat with 42 chromosomes arose. It is considered a hexaploid, with three sets of chromsomes, AABBCC. AA came from Einkorn wheat, BB, from the wild grass Aegilops speltoides, and CC from the Wild grass Aegilops squarrosa.