01299nas a2200193   4500008004100000245011600041210006900157260001200226300001400238490000700252520062700259653002300886653001500909653000900924100001600933700002100949700001900970856011600989       1997                        eng d00aSoil in relation to distribution and growth performance of Isoetes dixitei Shende in the Western Ghats of India0 aSoil in relation to distribution and growth performance of Isoet  c1997///  a317 - 3220 v383 aSoils collected from the natural habitats of I. dixitei Sende have been analysed for the available plant nutrients. The amount of nutrients have then been correlated with the growth performance of this species. The preceding analysis reveals that the habit of plants of I. dixitei are influenced by many overriding soils. However, the occurrence of stunted growth of some populations may be attributed to a comparatively high zinc and copper contents in the soils since these two minerals have been found to exhibit a significant though negative correlation with the plant lengths of the various populations of I. dixitei.10aGrowth performance10aI. dixitei10aSoil1 aWagai, S.O.1 aSrivastava, G.K.1 aSrivastava, M.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0031390381&partnerID=40&md5=8ddd377723a6deeecdee3a6d2352cba001222nas a2200145   4500008004100000245009900041210007000140260001200210300001400222490000700236520068500243100001400928700001800942856011600960       1997                        eng d00aLevels and Patterns of Genetic Variation in Isoëtes karstenii with Observations on I. palmeri0 aLevels and Patterns of Genetic Variation in Isoëtes karstenii wi  c1997///  a104 - 1150 v873 aGenetic variation was surveyed in eleven populations from throughout the range of the diploid Isoëtes karstenii, as well as in two populations of a closely related tetraploid, I. palmen, using allozyme electrophoresis. Genetic variation was high in I. karstenii and appears to be highly structured, as evidenced by analyses of F-statistics and genetic vs. geographic distance. No fixed unique alleles were found that could distinguish between I. karstenii and I. palmeri, although one allele was observed that was unique to I. palmeri. These analyses confirm earlier observations suggesting low levels of interpopulational gene flow and have implications for sampling strategies.1 aSmall, R.1 aHickey, James  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0343254203&partnerID=40&md5=c845f506b7c6840260fe7532b60a886d01207nas a2200193   4500008004100000245012200041210006900163260001200232300001400244490000700258520051300265653002600778653001500804653002500819653001700844100001800861700001800879856011600897       1997                        eng d00aAppalachian quillwort (Isoetes appalachiana, sp. nov.; Isoetaceae), a new pteridophyte from the eastern United States0 aAppalachian quillwort Isoetes appalachiana sp nov Isoetaceae a n  c1997///  a118 - 1330 v993 aIsoetes appalachiana, sp. nov., is an element of the I. engelmannii complex of North America. Its distinct cytology, spore morphology, and distribution are illustrated and described. Although widely distributed in the eastern United States, it appears to be most common in the Appalachian Mountains. Isoetes appalachiana is tetraploid; it is suspected to be an allopolyploid which evolved from the chromosome doubling of I. X altonharvillii, the sterile hybrid between I. engelmannii (s. str.) and I. valida.10aAppalachian Mountains10aIsoetaceae10aIsoetes appalachiana10aPteridophyte1 aBrunton, D.F.1 aBritton, D.M.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0013681071&partnerID=40&md5=ca09a6b7a394918dfcfa73009b9ad85b01521nas a2200217   4500008004100000245013200041210006900173260001200242300001400254490000700268520073400275653002001009653002301029653003901052653001501091653002801106100002001134700001501154700001801169856011601187       1997                        eng d00aIsoetes x carltaylorii (Isoetes acadiensis x Isoetes engelmannii), a new interspecific quillwort hybrid from the Chesapeake Bay0 aIsoetes x carltaylorii Isoetes acadiensis x Isoetes engelmannii   c1997///  a301 - 3090 v753 aIsoetes acadiensis Kott is a plant of the Maritime provinces of Canada and the northeastern United States. In the Chesapeake Bay region, this quillwort has previously ben misidentified as Isoetes riparia Engelm., Isoetes saccharata Engelm., or Isoetes saccharata var. reticulata A.A. Eaton, Isoetes x carltaylorii hyb. nov. is the hybrid between I. acadiensis (2 = 44) and Isoetes engelmannii A. Braun (2n = 22). This is the first report of a hybrid with I. acadiensis. An apparently sterile triploid (2n = 33), this rate plant of freshwater tidal marshes has the predicted range of sizes and megaspore features of a hybrid. This brings to 14 the number of interspecific quillwort hybrids described from North America since 1985.10aIsoetes riparia10aIsoetes saccharata10aIsoetes saccharata var. reticulata10aMegaspores10atidal freshwater rivers1 aMusselman, L.J.1 aBray, R.D.1 aKnepper, D.A.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0030617837&partnerID=40&md5=7b586defd299685d84514045c5efee0d01396nas a2200133   4500008004100000245009500041210006900136260001200205300001400217490000800231520089300239100001401132856011601146       1997                        eng d00aPlant size and fertility of Isoetes lacustris L. in 20 lakes of Scandinavia: A field study0 aPlant size and fertility of Isoetes lacustris L in 20 lakes of S  c1997///  a171 - 1850 v1393 aA relationship between the individual size and fertility of Isoetes lacustris in the habitat centres of different lakes was found. The maximum (mean) rosette size was 202.2 cm2 and the maximum (mean) number of macrospores in a sporangium was 113.4; the minimum (mean) values were 13.8 cm2 and 30.6 spores. Further correlations between vitality and fertility parameters were established. It is suggested that the main ecological factors responsible for the differences found in the lakes are effects of climate (including water temperature and duration of seasonal growth), which cause the differences in rosette size and fertility. The percentage of individuals with fertile sporangia was lowest in the slightly humic lakes with boreal climate and short summers, and highest in the clear lakes with temperate climate and long summers. Isoetes individuals showed increased size with depth.1 aVöge, M.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0343052607&partnerID=40&md5=3be747f4cb73f24bc9d8880018c16bd101895nas a2200133   4500008004100000245013500041210006900176260001200245300001400257490000800271520135200279100001401631856011601645       1997                        eng d00aNumber of leaves per rosette and fertility characters of the quillwort (Isoetes lacustris L.) in 50 lakes of Europe: A field study0 aNumber of leaves per rosette and fertility characters of the qui  c1997///  a415 - 4310 v1393 aIsoetes lacustris L. was studied in 35 lakes in the main area of distribution (N and W Europe), plus some other lakes outside of this area, where the species is present. By using SCUBA equipment fertile plants were selected randomly and several morphological and fertility characters were studied. It was found that there was a relationship between: a) the (mean) number of leaves per rosette, and the (mean) number of spores per macrosporangium, b) the number of leaves, and the number of macrosporangia per plant. The number of spores per macrosporangium is related directly to the percentage of fertile plants in the part of the population studied. A low number of leaves per rosette is a fair indication of a low number of macrospores in a sporangium and also a low number of macrosporangia per plant, anti the low number of spores points to a low percentage of fertile individuals in the part of the population studied. It is suggested that the often rapid decline of quillwort in lakes of Central Europe may be a self-accelerating process. In the N European lakes, numbers of leaves and spores have an inverse relationship to the colour of the water. In the W European lake sites, the height of the rosettes is correlated to the Secchi depth. No relationship between plant features and water characteristics (pH and conductivity) were found.1 aVöge, M.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0342617829&partnerID=40&md5=e5b61ab9a7b00c72dbe6bce9554fbc2f