Chromosome numbers of the Medicago sativa complex in Turkey

Turkish representatives of the Medicago sativa complex comprise three basic morphological classes distinguishable by the following: (1) purple flowers, coiled pods; (2) yellow flowers, uncoiled pods; (3) intermediates and recombinants between 1 and 2. Chromosome determinations were made for 329 plants representing 35 cultivated (alfalfa) and 87 wild populations. All cultivars collected fell into class 1 and were tetraploid (2n = 4x = 32). Wild plants representative of all three morphological classes were found at both the diploid (2n = 2x = 16) and tetraploid (2n = 4x = 32) level, and examples of hybrid zones between classes 1 and 2 were common at both levels. Most populations appeared to contain plants at the same ploidy level, but a few contained a mixture of both diploids and tetraploids, and at several locations diploid and tetraploid populations grew adjacent to each other. Tetraploids were widespread across Turkey whereas diploids were confined to the northeast region.