EVOLUTION OF POLYPLOIDS Reference: Harlan and deWet (1975) Origins of Polyploids Literatures relating to evolution of polyploids
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چکیده
Class I: Chromosome increase occurs in the first generation through the union of gametes one or both of which are unreduced. Can occur following selfor crosspollination. Class II: Chromosome doubling occurs in offspring of a hybrid with meiotic disturbances leading to unreduced gametes. It’s a second generation phenomenon: F2, BC1 or F1 crossed to a third parent. Class III: Chromosomal doubling occurs in somatic tissues. Mitotic event!
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Polyploid and hybrid evolution in roses east of the Rocky Mountains.
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