| Pseudoroegneria A. Love, established by Love in 1980 according to genome constitution, is a small genus of Triticeae Dumortier (Poaceae). Its basic St genome is one of the most important genomic components, present in more than half of the perennial Triticeae species. This genus includes about 15-20 species, with its species occurring on open rocky from the Middle East and Transcaucasia across Central Asia and Northern China to Western North America. No Pseudoroegneria species was reported in Flora Reipublicae Popularis Sinicae and local Floras in China. In fact, as now, it is reported that there were three species and one subspecies of Pseudoroegneria in China. According to the studies on morphology, cytogenetics and molecular marker, R. alashanica, distributing in Ninxia, China, and & magnicaespes, distributing in Xinjiang, China, may be the species of Pseudoroegneria in China. These Pseudoroegneria species are exceptionallydrought tolerant and have excellent forage quality.Pseudoroegneria is an important perennial genus of Triticeae Dumortier (Poaceae). Being an important genetic resource, it is of significance to improvement of Triticeae cereal crops. However, the origin and definition of the genus, precisetaxonomic ranks and relationships among the species in the genus have been under discussion since it was established. So, Biosystematic and geographical distribution studies on Pseudoroegneria species would provide theoretical foundation for using this genus plants to breed Triticeae crops and herbage. Meanwhile, these studies are of significance to discuss the origin and evolution of the polyploid genera in China, such as Elymus L., Elytrigia Desv., Roegneria C. Koch., Kengyilia Yen et Yang and Hystrix Moench. The present study systematically evaluated Pseudoroegneria on karyotypes, gliadin, RAPD and RAMP markers. The main results showed as following:1. Karyotypes of seven species and two subspecies in Pseudoroegneria and two species in Roegneria were investigated. The karyotype formulae were as follows: P. spicata, 2n=2x=14=12m(2sat)+2sm; P. strigosa, 2n=2x=14=12m+2sm(2sat); P. strigosa ssp. aegilopoides, 2n=2x=14=12m(2sat)+2sm; P. stipifolia, 2n=2x=14= 12m(2sat)+2sm(2sat); P. libanotica, 2n=2x=14=10m+4sm(4sat); P. geniculata, 2n=4x=28=20m+8sm(2sat): P. geniculata ssp. scythica, 2n=4x=28=24m(2sat)+ 4sm; P. gracillima, 2n=4x=28=24m(2sat)+4sm; P. elytrigioides, 2n=4x=28=22m +6sm (4sat); R. alashanica, 2n=4x=28=22m+6sm(2sat); R. magnicaespes, 2n=4x=28=22m+ 6sm. Seven taxa of them were reported for the first time. The karyotypes of R. alashanica, R. magnicaespes, P. elytrigioides and P. geniculata were similar, of all being 2A. According to the karyotypes, morphology and studies on cytogenetics and molecular marker, these two taxa, R. alashanica and R. magnicaespes, may be the species in Pseudoroegneria in China.2. The gliadin genetic polymorphism among nine species and one subspecies in Pseudoroegneria and five species in Roegneria were analyzed by using acidpolyacrylamide gel electrophoresis(A-PAGE). The results showed as follows: (1) A total of 26 gliadin bands were separated by electrophoresis, of all showing polymorphism, which amounts to 100%, which may be caused by the characters of extensive geographical regions and cross pollination; (2) Distinct gliadin genetic variations were presented among the populations. The gliadin genetic variations among different species were more abundant than that of different accessions, and the gliadin patterns can be used as a fingerprint to survey different materials in Pseudoroegneria; (3) R. alashanica and R. magnicaespes were grouped with Pseudoroegneria species, indicating that these two Roegneria species were closer to the species of Pseudoroegneria than to the species of Roegneria; (4) The gliadin results were basically comparable with those obtained from studies on morphology, cytology and cytogenetics. Therefore, the gliadin patterns data can be used to investigate genetic variation and biosystematic relationships among species in...
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