Figure 7.22 Polyploidy in wheat. Starting with a diploid species of wheat, plant breeders have bred new species that contain four or six sets of chromosomes. (a) The ancestral einkorn wheat (Triticum boeoticum) has two sets of chromosomes and small seeds. (b) Durum wheat (Triticum durum), which is used to make pasta, was bred to have four sets of chromosomes. It has medium-sized seeds. (c) Common wheat (Triticum aestivum), which is used for bread and other baked goods, was bred to have six sets of chromosomes. It has the largest seeds.