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Fiber Evolution

Introgression Populations
Homoeolog-specific Profiling
Genetic Networks & Phenotype
Effects of Selection
Sequence Capture

Genetic and Physical mapping resources
Comparative BAC Sequencing
Genome Sequence Resources
EST D-genome map
EST Resources

Web Database
Education and Outreach
Significance for cotton industry
Cotton Literature
Cotton Links
Wendel Lab
PGML (Paterson Lab)
Udall Lab

Lists & protocols
How to
CEGC Site Search

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Genome Evolution

Evolutionary history of the genus. As Gossypium diversified and colonized arid regions of the globe it underwent extensive chromosomal evolution. Presently, eight diploid genome groups (A through G, plus K) are recognized among the 50 species. Relationships within and among the various genome groups have been addressed in detail. Genome groups largely correspond to monophyletic lineages. This information has been embodied in our synthesis of relationships and of genome evolution, which reveals four major lineages of diploid species corresponding to three continents.

Phylogenetic framework and genome size variation. Gossypium contains 45 diploid (n = 13) and five allopolyploid (n = 26) species, the latter with two genomes, A and D, from species in different hemispheres. A- and D-genome groups diverged ~ 5-10 MYA. Allopolyploid cottons originated following trans-oceanic dispersal of an A-genome progenitor to the New World. Arrows indicate taxa representing the best living models of the species involved in allopolyploid formation. Allopolyploids diversified during the Pleistocene into three lineages, of which two include the commercially important species, G. hirsutum (upland cotton) and G. barbadense (Pima cotton), each domesticated within the last 4000-7000 years.

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