Chromosome number and karyotype of Phaenospermateae and Duthieeae (Poaceae), with reference to their systematic implications
7 June 2018
zhang, zhongshuai; Li, Linglu; Chen, WenliRecent molecular phylogenetic studies indicate that Phaenospermateae and Duthieeae are among the early diverging lineages of Pooideae and they are closely related to each other. Here, we test this from a cytotaxonomical viewpoint. The monotypic tribe Phaenospermateae, represented by Phaenosperma globosum, has a chromosome number of 2n = 2x = 24 and a fairly symmetric karyotype consisting of 22 median (m) and 8 submedian (sm) chromosomes varying in length between 1.8–3 μm. Duthieeae, represented by Duthiea brachypodium, Sinochasea trigyna, Stephanachne monandra and Stephanachne pappophorea, also share the chromosome number of 2n = 2x = 24 and similar symmetric karyotypes with the chromosomes varying in length between 1.4–5 μm. Thus, the close relationship of Phaenospermateae and Duthieeae is corroborated.