Fig. 4.

Genome-wide synteny analysis for CCD genes among allopolyploid and diploid Gossypium species. a Synteny analysis between G. hirsutum and two diploid species, G. arboreum and G. raimondii. b Synteny analysis between G. barbadense and two diploid species, G. arboreumand G. raimondii. Green lines link gene pairs between G. arboreum and G. hirsutum or G. barbadense; dark red lines connect gene pairs between G. raimondii and G. hirsutum or G. barbadense; light red lines bridge gene pairs between At- and Dt-subgenome in allopolyploid cotton. Red boxes indicate chromosomes of G. arboreum, dark boxes indicate chromosomes of G. raimondii, and green boxes indicate chromosomes of G. hirsutum or G. barbadense