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=da8d4d4668c03846b51b3df5877e860202081nas a2200241   4500008004100000245012600041210007000167260001200237300001200249490000700261520129100268653001701559653001501576653002201591653002301613653000901636100001601645700001201661700001601673700001701689700001601706856011701722       2005                        eng d00aGenetic variation within the endangered quillwort Isoëtes hypsophila (Isoetaceae) in China as evidenced by ISSR analysis0 aGenetic variation within the endangered quillwort Isoëtes hypsop  c2005///  a89 - 980 v823 aThe genetic diversity of 56 individuals of Isoëtes hypsophila Hand.-Mazz. from China was investigated by ISSR. Twelve primers were screened from 65 primers, and a total of 119 DNA fragments were scored, of these, 82% were polymorphic bands, which indicated that high levels of genetic variation existed in the natural populations. Genetic diversity varied greatly among populations with the percentage of polymorphic band (PPB) values ranging from 8 to 35%. An analysis of molecular variance (AMOVA) was used to apportion the variation between regions, among populations within regions, and within populations. Results indicated that most of the variance (85%) occurred between Yunnan and Sichuan. The variances among populations within regions and within populations, however, were only 5 and 10%, respectively. In the among-population analysis, the larger part of genetic variation (77%) resided among populations, and less (23%) presented differences within populations. UPGMA cluster analysis showed that there was no distinct genetic differentiation between populations from Sichuan province. A number of causes including limited gene flow, genetic drift and inbreeding might have led to these observed genetic profiles of I. hypsophila. © 2005 Elsevier B.V. All rights reserved.10aConservation10aEndangered10aGenetic variation10aIsoetes hypsophila10aISSR1 aChen, J.-M.1 aLiu, X.1 aWang, J.-Y.1 aRobert, G.W.1 aWang, Q.-F.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-20444420155&partnerID=40&md5=c58709593caeba345cf50c4fba7d621302208nas 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=f310ff0165e440259efb4b7c64314743