Phylogenetic analysis of cotton Sus genes and other plant Sus homologs. Unrooted phylogenetic tree of plant Sus proteins constructed using the neighbor-joining method with MEGA 5.0 program. Isozymes and corresponding plant species are: cotton, GaSus1 to 7 (this study); Potato, StSus1 to 4 ; Pea, PeaSus1 to 3 ; Wheat, TaSus1 and TaSus2 ; Arabidopsis thaliana, AtSus1 to 6 ; Rice, OsSus1 to 6 ; Lotus japonicus, LjSus1 to 6 ; Citrus, CitSus1, CitSus2 and CitSusA ; Bamboo, BoSus1 to 4 ; Tomato, LeSus1 and LeSus2 ; Carrot, DcSus1 and DcSus2 ; Maize, ZmSh1, ZmSus1 and ZmSus3 ; Barley, HvSus1 and HvSus2 ; Sugarbeet, SbSS1 ; Sorghum, SbSus2 (accession no. FJ513325); Sugarcane, SoSus2 (accession no. AY118266); Populus, PtSus1 to 7 .