Instituto de Botánica del Nordeste (UNNE-CONICET), Casilla de Correo 209, 3400 Corrientes, Corrientes Province, Argentina;
Am J Bot. 2002 Apr;89(4):551-8. doi: 10.3732/ajb.89.4.551.
Turnera sidoides, with the most southerly distribution of all Turnera species in America, is a complex of obligately outcrossing perennial herbs. Karyotypes of the five subspecies of T. sidoides (x = 7) are described for the first time utilizing root-tip mitotic metaphases. Different ploidy levels were found for all of the subspecies, ranging from diploid to octoploid. The results obtained, coupled with available meiotic and preliminary biosystematic data, support the hypothesis of autopolyploidy within this species complex. Although detailed karyotype analysis shows a high degree of intraspecific uniformity, subspecies may be differentiated by the number, type, and position of satellites, suggesting that chromosome rearrangements may also be involved in the karyotypic evolution of T. sidoides. Karyotype data, coupled with morphological and anatomical features, suggest the removal of T. sidoides from series Leiocarpae.
Turnera sidoides 是美洲分布最靠南的 Turnera 物种复合体，是一种强制性异交的多年生草本植物。首次利用根尖有丝分裂中期相描述了 T. sidoides 的五个亚种（x = 7）的核型。所有亚种的倍性水平都不同，从二倍体到八倍体不等。获得的结果，加上现有的减数分裂和初步生物系统学数据，支持了该物种复合体中同源多倍体的假说。尽管详细的核型分析显示出高度的种内均匀性，但亚种可能通过卫星的数量、类型和位置来区分，这表明染色体重排也可能参与了 T. sidoides 的核型进化。核型数据，加上形态和解剖学特征，表明将 T. sidoides 从 Leiocarpae 系列中移除。
