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Deyeuxia sorengii B. Paszko & W. L. Chen, a new species of Deyeuxia from the Qinghai-Tibetan Plateau, China, is described and illustrated. The new species is morphologically similar to D. zangxiensis P. C. Kuo & S. L. Lu, but differs from it by having a well-developed and conspicuously hairy rachilla prolongation and a straight awn. Deyeuxia sorengii occurs in alpine meadows of central Xizang and central Qinghai. The first records of Deyeuxia zangxiensis are reported from western and eastern Xinjiang and northeastern Qinghai (China). [ABSTRACT FROM AUTHOR]

We conducted a detailed study of the morphological and cytological variation in seven populations of the Poa orinosa complex along an ecological gradient in northeastern China. Three of the populations were at different elevations in wooded habitats; three were in habitats dominated by grasses other than Poa; and one was in a shrub-steppe habitat. Plants from two of the wooded sites were diploid; those from the third wooded site were primarily octoploid. Plants from two of the grassy sites were tetraploid; those from the third grassy site were hexaploid. The seventh population, located in a shrub-steppe habitat, was diploid. Twenty-four morphological characters were scored on specimens from each site. Plants from the three wooded sites and the lowest grassy site differed from those from the other three sites in having longer culms, internodes and sheaths. The similarity of the tetraploid plants to the diploid plants suggested that they may be autotetraploids. Similarly, the morphological similarity of the octoploid population to the two diploid populations suggested that it too may be an autopolyploid. The morphological distinction of the hexaploid population suggests that it has incorporated a genome not present in the other populations. [ABSTRACT FROM AUTHOR]

The generic placement of Piptatherum kuoi (Poaceae, Stipeae) has long been controversial. Recent molecular phylogenetic analyses indicate that Piptatherum kuoi should be transferred to Patis. Here, we present cytological support for this transfer and discuss morphological differences and similarities. Piptatherum kuoi has a chromosome number of 2n = 46 with the chromosomes varying in length between 1.1 and 3.1 μm, and the symmetrical karyotype 2n = 26m + 16sm + 4st (2sat). Karyological characters of Piptatherum kuoi, including chromosome number, size, and karyotype asymmetry, thus all agree with those of species of Patis, but are different from those of other species of Piptatherum. The transfer of Piptatherum kuoi to Patis is thus corroborated. [ABSTRACT FROM AUTHOR]