01188nas a2200241   4500008004100000245007900041210006900120260001200189300001400201490000700215520045700222653001000679653001400689653001500703653001200718653001400730653002700744100001600771700001200787700001700799700001400816856011600830       2002                        eng d00aIsoetes yunguiensis (Isoetaceae), a new basic diploid quillwort from China0 aIsoetes yunguiensis Isoetaceae a new basic diploid quillwort fro  c2002///  a587 - 5910 v123 aIsoetes yunguiensis, a basic diploid species with a chromosome number of 2n = 22, is described and illustrated. This species occurs on the Yunnan-Guizhou Plateau in southwest China. It is similar to I. japonica in its appearance and emergent aquatic habit. Herbarium specimens of I. yunguiensis previously have been misidentified as I. japonica. Isoetes yunguiensis differs from I. japonica in megaspore and microspore morphology and chromosome number.10aChina10aEast Asia10aIsoetaceae10aIsoetes10aQuillwort10aYunnan-Guizhou Plateau1 aWang, Q.-F.1 aLiu, X.1 aTaylor, W.C.1 aHe, Z.-R.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0036939584&partnerID=40&md5=da8d4d4668c03846b51b3df5877e860202208nas a2200217   4500008004100000245005800041210005600099260001200155300001400167490000700181520157700188653001001765653001401775653001201789653001101801653002101812100001201833700001201845700001601857856011701873       2008                        eng d00aSpore morphology of Isoëtes (isoëtaceae) from China0 aSpore morphology of Isoëtes isoëtaceae from China  c2008///  a479 - 4890 v463 aMicromorphological characters of mega- and microspores of five Isoëtes species from China were observed under scanning electron microscope (SEM). Megaspores of I. hypsophila have a levigate ornamentation, and are 358 μm in diameter (mean, n=30), microspores of this species have a gyrus ornamentation, and are 22 μm in length (mean, n=30); megaspores of I. yunguiensis have a cristate-reticulate ornamentation, with a size of 390 μm in diameter (mean, n=30), while microspores nearly smooth with some fine granulates, and with a size of 22 gm in length (mean, n=30); megaspores of I. taiwanensis are tuberculate and 312 μm in diameter (mean, n=30), echinate microspores are 24 μm in length (mean, n=30); cristate megaspores of I. sinensis are 409 μm in diameter (mean, n=30), and echinate microspores are 28 μm in length (mean, n=30); megaspores of I. orientalis have a cristate-reticulate ornamentation, with diameter of 420 μm (mean, n=30), microspores of this species have an echinate-tuberculate ornamentation with a size of 34 μm in length (mean, n=30). Based on the morphological characters of spores and chromosome numbers among taxa, it was found that mean spore size in each species of Isoëtes generally reflected the ploidy level. I. hypsophila, I. yunguiensis and I. taiwanensis, with smaller mean spore size, are diploidy with 2n=22; I. sinensis (2n=44) and I. orientalis (2n=66), with larger mean spore size, are polyploidy. The spore morphology of Isoëtes still plays an important role in identification and classification of Isoëtes from China.10aChina10aEvolution10aIsoetes10aOrigin10aSpore morphology1 aLiu, X.1 aLiu, H.1 aWang, Q.-F.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-57349117891&partnerID=40&md5=f310ff0165e440259efb4b7c6431474301875nas a2200229   4500008004100000245009000041210006900131260001200200300001200212490000600224520112400230653001701354653002201371653001201393653004401405653002401449100001301473700001701486700001201503700001301515856011701528       2007                        eng d00aGenetic diversity in Isoetes yunguiensis, a rare and endangered endemic fern in China0 aGenetic diversity in Isoetes yunguiensis a rare and endangered e  c2007///  a46 - 490 v23 aIsoetes yunguiensis is an endangered and endemic fern in China. Field survey indicated that only one population and no more than 50 individuals occur in the wild. The genetic variation of 46 individuals from the population remaining at Pingba (Guizhou Province, China) was assessed by Random Amplified Polymorphic DNA (RAPD) finger-printing. Twelve primers were screened from sixty ten-bp arbitrary primers, and a total of 95 DNA fragments were scored. Of these, 62.1% were polymorphic loci, which indicated that high level genetic variation existed in the natural population. The accumulation of genetic variation in the history of the taxon and the apparent minimal reduction effect on genetic diversity following destruction of habitat might be responsible for the high level genetic diversity presently remaining in the I. yunguiensis population. However, with the continuing decrease of population size, the genetic diversity will gradually be lost. We suggest that the materials from the extant population should be used for re-establishment of the populations. © 2007 Higher Education Press and Springer-Verlag.10aEndemic fern10aGenetic diversity10aIsoetes10aRandom amplified polymorphic DNA (RAPD)10aRare and endangered1 aChen, J.1 aGituru, W.R.1 aLiu, X.1 aWang, Q.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-33847396236&partnerID=40&md5=ee6f56a9a5fcf2d93d7218f43862d556