Desiccation and rehydration experiments on leaves of 43 pteridophyte species.ABSTRACT.--We conducted desiccation des·ic·ca·tion n. The process of being desiccated. des  ic·ca and rehydration rehydration /re·hy·dra·tion/ (-hi-dra´shun) the restoration of water or fluid content to a patient or to a substance that has become dehydrated. re·hy·dra·tion n. 1. experiments on the detached leaves of 43 pteridophyte species to assess the variability of drought adaptation strategies among pteridophytes. We found complete grades of desiccation responses from poikilohydric to homoiohydric strategies and within the latter category from mesomorphism to xeromorphism. These results suggest that pteridophytes have repeatedly evolved a wide variety of drought adaptation strategies (poikilohydry and xeromorphism at least 12 and 6 times, respectively) that are not adequately described by a simple distinction between homoiohydry and poikilohydry. Key Words.--drought adaptation strategies, homoiohydry, mesomorphism, poikilohydry, xeromorphism, desiccation, rehydration ********** Ferns and lycophytes are most abundant and species-rich in humid habitats (e.g., Kessler, 2001), but a considerable number of species have also become adapted to arid conditions (Pickett, 1931; Gaff, 1977; Page, 2002). Most pteridophytes can be characterized as mesomorphic mes·o·mor·phic adj. 1. also mes·o·mor·phous Of, relating to, or existing in a state of matter intermediate between liquid and crystal. 2. Of or relating to a mesomorph. and without any special adaptations to drought stress. However, numerous taxa show a variety of adaptive strategies The expression adaptive strategies is used by anthropologist Yehudi Cohen to describe a society’s system of economic production. Cohen argued that the most important reason for similarities between two (or more) unrelated societies is their possession of a similar to drought stress and desiccation (Table 1). These adaptive strategies have long attracted the attention of plant physiologists, and detailed ecophysiological studies have been performed on a number of taxa, including a variety of cheilanthoid ferns (Pickett and Manuel, 1926; Iljin, 1931; Hevly, 1963; Quirk and Chamber, 1981), Hymenophyllum (Hartel, 1940 a, b; Hietz and Briomes, 1998; Proctor, 2003), Asplenium ceterach L. (Rouschal, 1938), Polypodium vulgare L. (Kappen, 1964), and in particular Pleopeltis polypodioides Pleopeltis polypodioides (Resurrection fern; syn. Polypodium polypodioides) is a species of creeping, course-textured fern native to the Americas and Africa. The evergreen fronds of this fern are 25 cm high by 5 cm wide and monomorphic. (L.) E.G. Andrews & Windh. and its relatives (Pessin, 1924, 1925; Stuart, 1968; Muller et al., 1981). These studies focussed on taxa with particularly conspicuous water drought adaptations, especially poikilohydry, and covered only a small range of the phylogenetic phy·lo·ge·net·ic adj. 1. Of or relating to phylogeny or phylogenetics. 2. Relating to or based on evolutionary development or history. and physiological variability within ferns and lycophytes. Accordingly, there is currently no taxonomically tax·o·nom·ic also tax·o·nom·i·cal adj. Of or relating to taxonomy: a taxonomic designation. tax representative sampling of drought adaptation strategies for pteridophytes. For example, poikilohydry has been documented in 19 pteridophyte genera genera, in taxonomy: see classification. (Proctor and Pence, 2002), belonging to at least 12 independent evolutionary lineages as recognized in the phylogenies of Schneider et al. (2004) and Smith et al. (2006). The anatomical, morphological, and physiological mechanisms involved in poikilohydry differ among several of these lineages. A conspicuous example of contrasting mechanisms is presented by the filmy-ferns with their one-cell-thick leaves that rehydrate re·hy·drate v. 1. To cause rehydration of something. 2. To replenish the body fluids of an individual. by direct water contact (Hartel, 1940 a, b) and Pleopeltis polypodioides and its relatives that absorb water through specially adapted epidermal Epidermal Referring to the thin outermost layer of the skin, itself made up of several layers, that covers and protects the underlying dermis (skin). Mentioned in: Antiangiogenic Therapy, Histiocytosis X epidermal scales (Muller et al., 1981). In other cases, a full transition from poikilohydric to homoiohydric behavior has been documented within a single species. For example, European Polypodium vulgare has homoiohydric responses in winter when water stress is negligible, and poikilohydric responses in summer when dry spells are frequent (Kappen, 1964). Thus, the simple distinction between these contrasting drought stress adaptations (Table 1) hide a wide spectrum of different, intermediate, or mixed strategies (Proctor and Tuba, 2002). Given the taxonomically and physiologically biased sample A biased sample is a statistical sample of a population where some members of the population are less likely to be included than others. An extreme form of biased sampling occurs when certain members of the population are totally excluded from the sample (that is, they have zero of studies of drought adapation strategies among pteridophytes, the aim of the present study was to assess the variability of drought stress strategies among pteridophytes by experimentally desiccating and rehydrating excised leaves (leafy stem sections in the case of Selaginella) from 43 pteridophytes belonging to a wide range of taxonomic tax·o·nom·ic also tax·o·nom·i·cal adj. Of or relating to taxonomy: a taxonomic designation. tax groups and morphological types. Our basic assumption was that the different adaptive strategies could be distinguished by the reaction of leaves to desiccation and rehydration (Table 1). This applies to water loss, since most transpiration transpiration, in botany, the loss of water by evaporation in terrestrial plants. Some evaporation occurs directly through the exposed walls of surface cells, but the greatest amount takes place through the stomates, or intercellular spaces (see leaf). takes places through the leaves. Water uptake in ferns mostly takes place through the roots, and our experiments with excised leaves can only distinguish between poikilohydric taxa capable of water absorption through leaves and homoiohydric taxa incapable of doing so. Historically, the study of detached leaves has provided reliable insights into plant physiology Plant physiology That branch of plant sciences that aims to understand how plants live and function. Its ultimate objective is to explain all life processes of plants by a minimal number of comprehensive principles founded in chemistry, physics, and in general (Leprince and Golovina, 2002) and due to the difficulty of drying and weighing whole plants, has been the method of choice for desiccation experiments with ferns (Pessin, 1924, 1925; Pickett and Manuel, 1926; Iljin, 1931; Rouschal, 1938; Hartel, 1940 a, b; Kappen, 1964; Stuart, 1968; Muller et al., 1981; Quirk and Chamber, 1981; Proctor, 2003). MATERIAL AND METHODS Leaves or stem sections of 43 pteridophyte species were obtained from the living collection of the Botanical Garden botanical garden, public place in which plants are grown both for display and for scientific study. An arboretum is a botanical garden devoted chiefly to the growing of woody plants. of the University of Gottingen, Germany (Table 2). Species were selected to cover a wide range of taxa and life forms, with a focus on groups exhibiting an obvious variety of adaptations to drought stress (Table 1) and included 13 mesomorphic, 11 poikilohydric, four xeromorphic, two drought-deciduous, one water-impounding, and 12 intermediate species. An intermediate category was established for species that could not be unambiguously placed in either the mesomorphic or xeromorphic categories. No succulent species were available for study. Experiments were conducted with excised leaves, pinnae (in the case of large fronds), or stem section (Selaginella). Total water content of fully hydrated leaves was determined prior to the desiccation experiment. Freshly cut leaves from well-watered plants were fully hydrated by wetting their surfaces and placing them overnight in closed plastic bags. Leaf surfaces were then dried with tissue paper and briefly dried at ambient temperature Outside temperature at any given altitude, preferably expressed in degrees centigrade. , and the leaves weighed to the closest 0.001 g on a precision scale. Total dry mass was determined by placing the leaves in a drying oven for two to three days at 105[degrees]C until weight constancy con·stan·cy n. 1. Steadfastness, as in purpose or affection; faithfulness. 2. The condition or quality of being constant; changelessness. Noun 1. was achieved. Total water content was then calculated by subtracting its dry mass from the fully hydrated mass. In the actual desiccation and rehydration experiments, different fully hydrated leaves (see above) were placed in a drying oven at 40[degrees]C for 20 different time periods (0.5, 1, 2, 3 ..., 14, 15, 18, 24, 30, and 36 hours) and weighed afterwards. These leaves were then wetted and placed in closed plastic bags for one to three days until reaching weight constancy. Water loss and absorption were expressed as the percent value of the total water content of leaves for each species. Leaves were considered to be lethally damaged when at least 50% of the lamina LAMINA - A concurrent object-oriented language. ["Experiments with a Knowledge-based System on a Multiprocessor", Third Intl Conf Supercomputing Proc, 1988]. tissue showed necroses. Replicates (five each) were made of only three species (Adiantum capillus-veneris L., Blechnum brasiliense Desv., and Pteris quadriaurita Retz.) due to the limited material available of most species. We calculated the following parameters: desiccation resistance, the percentage of the total water contents that could be lost before leaves were lethally damaged; desiccation delay, the time until the leaves became lethally damaged; recuperation recuperation /re·cu·per·a·tion/ (-koo?per-a´shun) recovery of health and strength. recuperation, n the process of recovering health, strength, and mental and emotional vigor. capacity (resaturation), the percentage of the original water contents that was regained at the point of desiccation resistance. RESULTS The studied species showed a wide variation of all measured parameters (Fig. 1, Table 2). For example, lethal desiccation levels were reached in different species after 1 to 36 hours and at water losses of 30-99%, as determined from the desiccation delay and desiccation resistance parameters, respectively (Table 2). It was not possible to discern distinct groups of species that could be assigned to specific drought adaptation strategies (Fig. 2). Because excised pinnae or stem sections were only used for a few, usually related species (five and six species, respectively), no formal test was possible of whether these samples differed systematically from species studied with entire leaves, but visual inspection of the results show no apparent trends. The three species with five replicate measurements each showed reproducible patterns, with measurements having on average a coefficient of variation Coefficient of Variation A measure of investment risk that defines risk as the standard deviation per unit of expected return. of 12%, which is much lower than the variation observed between species (54%). DISCUSSION To our knowledge, this is the first study to compare the desiccation and rehydration behavior of a large number of pteridophyte species with a consistent method. In the interpretation of the results it should be borne in mind that the experiment was conducted on detached leaves, and that the absolute values of the dehydration behaviors therefore do not correspond to the values of entire and intact living plants. This is especially relevant for the ability of the plants to rehydrate, because of the difficulty of accurately determining the health status of leaves based only on external visual examination. As a result of using excised leaves, some leaves were certainly more severely damaged by the handling than others, affecting their recuperation capacity. This is evident in Fig. 1, where, e.g., Cheilanthes myriophylla showed a wide variation of measurements, suggesting that some individual leaves might have been more strongly damaged than others. A general pattern observed for most species was the gradual decline in desiccation resistance and recuperation capacity with increasing desiccation time. The first of these declines clearly reflects the gradual loss of water over time, whereas the second one presumably pre·sum·a·ble adj. That can be presumed or taken for granted; reasonable as a supposition: presumable causes of the disaster. reflects the physiological or anatomical damage due to longer and stronger desiccation that reduces the ability of the leaves to rehydrate. Despite these unavoidable methodological shortcomings, the present study is comparable to previous desiccation experiments with ferns that also used detached leaves (Pessin, 1924, 1925; Pickett and Manuel, 1926; Iljin, 1931; Rouschal, 1938; Hartel, 1940 a, b; Kappen, 1964; Stuart, 1968; Muller et al., 1981; Quirk and Chamber, 1981; Proctor, 2003). [FIGURE 1 OMITTED] [FIGURE 2 OMITTED] Perhaps the most important result of our study is the high and gradual variability in the responses to desiccation and rehydration among the species examined. Some species showed patterns that could easily be attributed to a "classic" drought adaptation strategy. Examples included Asplenium mannii (mesomorphic) that died quickly after relatively limited loss of water (30%), Hemionitis palmata (poikilohydric) that survived loss of most (96%) of its water and tolerated desiccation for a long period of time (13 hours), and Polypodium scouleri (xeromorphic) that dried out most slowly (desiccation delay = 36 hours). However, most species showed intermediate patterns and considering all species together there were complete grades of desiccation and rehydration responses from poikilohydric to homoiohydric species and within the latter category from mesomorphic to xeromorphic species. The cline of mesomorphic and xeromorphic behaviors has also been documented within single species by Kappen (1964). As an example of variability within a given drought adaptation strategy we can compare the poikilohydric taxa Anemia and the cheilanthoid ferns (Cheilanthes, Hemionitis). One species of Anemia has been shown experimentally to be poikilohydric (Proctor and Pence, 2002), and our field experience with a number of other species in Bolivia also shows that these behave as poikilohydric species: their leaves roll up under drought stress and become brittle and brownish, but the plants can be readily rehydrated by placing them in plastic bags with water (M. Kessler, pers. obs.). However, in the experiments conducted here, two of three species of Anemia (marked by black arrows The Black Arrows, one of the predecessors of the current Royal Air Force Aerobatic Team, the Red Arrows, were an aerobatic demonstration team formed in the 1950s from 111 Squadron (treble-one). in Fig. 2) had a much lower desiccation resistance and desiccation delay than cheilanthoid ferns which are well-documented to be poikilohydric (Pickett and Manuel, 1926; Iljin, 1931; Hevly, 1963; Quirk and Chamber, 1981). Among the unambiguously poikilohydric species we measured water losses (desiccation resistance) of 74-99% (Table 2). This corresponds well with previous studies which have documented values of up to 94% water loss in Notholaena marantae R. Br. (Iljin, 1931), 95% in Polypodium vulgate Vulgate (vŭl`gāt) [Lat. Vulgata editio=common edition], most ancient extant version of the whole Christian Bible. Its name derives from a 13th-century reference to it as the "editio vulgata. (Losch, 2001), 97% in Pleopeltis polypodioides and relatives (Muller et al., 1981), and 96-98% in Asplenium ceterach (Rouschal, 1938). Looking at taxa with unusual strategies, the desiccation behavior of the two deciduous deciduous /de·cid·u·ous/ (de-sid´u-us) falling off or shed at maturity, as the teeth of the first dentition. de·cid·u·ous adj. 1. species (Adiantum capillus-veneris, Pellaea sagittata; triangles in Fig. 2) was intermediate between poikilohydric and mesomorphic species. The difference between these groups is therefore found in their response to low leaf water content, with deciduous species shedding their leaves or pinnae when they are too dry. There are also some species with mixed poikilohydric/ deciduous strategies, such as Argyrochosma nivea (Poir.) Windham. Our field experience with this species in the Bolivian Andes shows that at the beginning of the dry season dried-out plants can be readily rehydrated in wet plastic bags. Several months later at the end of the dry season, leaves had apparently died and pinnules had been shed, leaving only the naked rachises (M. Kessler, pers. obs.). It would be interesting to know if deciduousness de·cid·u·ous adj. 1. Falling off or shed at a specific season or stage of growth: deciduous antlers; deciduous leaves; deciduous teeth. 2. in pteridophytes is associated with an active recovery of nutrients or assimilates from the leaves, which would represent a distinct advantage over mesomorphic species that loose all tissue once the leaves are too dry. Considering the other unusual strategy, the only impounding species, A. nidus nidus /ni·dus/ (ni´dus) pl. ni´di [L.] 1. the point of origin or focus of a morbid process. 2. nucleus (2). , behaved like xeromorphic taxa. In conclusion, our study confirms the notion of Proctor and Tuba (2002) that plants have evolved a wide variety of drought adaptive strategies that are not adequately described by a simple distinction between homoiohydry and poikilohydry. The large number of cases in which poikilohydry has independently evolved in pteridophytes, at least 12 times and likely more often, suggests that different physiological mechanisms may have been developed to achieve the same adaptive response The adaptive response is a form of direct DNA repair in E. coli that is initiated against alkylation, particularly methylation, of guanine or thymine nucleotides or phosphate groups on the sugar-phosphate backbone of DNA. . A similar case can be made for xeromorphic adaptations, which appear to have evolved independently at least half a dozen times (M. Kessler, unpubl, data). A comparative study of the adaptive efficiency of these different evolutionary cases might yield interesting insights into the physiological constraints and possibilities present among pteridophytes. ACKNOWLEDGEMENTS We thank C. Lenschner and D. Hertel, Dept. of Plant Ecology, Univ. of Gottingen, for providing laboratory facilities, and M. Schwerdtfeger and the gardeners of the Botanical garden of the Univ. of Gottingen for providing plant material. Ruth Kirkpatrick, Jurgen Kluge (jargon) kluge - /klooj/, /kluhj/ (From German "klug" /kloog/ - clever and Scottish "kludge") 1. A Rube Goldberg (or Heath Robinson) device, whether in hardware or software. , and two anonymous reviewers provided useful comments on the study and manuscript. LITERATURE CITED GAFF, D. F. 1977. Desiccation-tolerant vascular plants of Southern Africa. Oecologia 31:95-109. HARTEL, O. 1940a. Physiologische Studien an Hymenophyllaceen I. Zellphysiologische Untersuchungen. Protoplasma 34:117-147. HARTEL, O. 1940b. Physiologische Studien an Hymenophyllaceen II. Wasserhaushalt und Resistenz. Protoplasma 43:490-515. HEVLY, R. H. 1963. Adaptations of cheilanthoid ferns to desert environments. J. Arizona Acad. Sci. 2:164-175. HIETZ, P. and O. BRIOMES. 1998. Correlation between water relations and within-canopy distribution of epiphytic ep·i·phyte n. A plant, such as a tropical orchid or a staghorn fern, that grows on another plant upon which it depends for mechanical support but not for nutrients. Also called aerophyte, air plant. ferns in a Mexican cloud forest cloud forest n. A tropical forest, often near peaks of coastal mountains, that usually has constant cloud cover throughout the year. cloud forest . Oecologia 114:305-316. ILJIN, W. S. 1931. Austrocknungsresistenz des Farnes Notholaena marantae R. Br. S. Protoplasma 8:322-330. KAPPEN, L. 1964. Untersuchungen fiber den Jahresverlauf der Frost-, Hitze- und Austrocknungsresistenz von Sporophyten einheimischer Polypodiaceen (Filicinae). Flora 155:123-166. KESSLER, M. 2001. Pteridophyte species richness  This article or section is in need of attention from an expert on the subject.Please help recruit one or [ improve this article] yourself. See the talk page for details. in Andean forests in Bolivia. Biodiv. Conserv. 10:1473-1495. LEPRINCE, O. and E. A. GOLOVINA. 2002. Biochemical and biophysical methods for quantifying desiccation phenomena in seeds and vegetative vegetative /veg·e·ta·tive/ (vej?e-ta?tiv) 1. of, pertaining to, or characteristic of plants. 2. concerned with growth and nutrition, as opposed to reproduction. 3. tissues. Pp. 111-146, in M. Black and H. W. Pritchard, eds. Desiccation and Survival in Plants, Drying Without Dying. CABI CABI Commonwealth Agricultural Bureaux International (UK) CABI Centre for Agriculture and Biosciences International (UK) CABI Colorado Association of Business Intermediaries CABI California Birth Index Publishing, New York New York, state, United States New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of . LOSCH, R. 2001. Wasserhaushalt der Pflanze. Quelle & Meyer, Wiebelsheim. MULLER, L., G. STAPNECKER and S. WINKLER Winkler may refer to:
PACE, C. N. 2002. Ecological strategies in fern evolution: a neopteridological overview. Rev. Palaeobot. Palynol. 119:1-33. PESSIN, L. J. 1924. A physiological and anatomical study of the leaves of Polypodium polypodioides. Am. J. Bot. 11:370-381. PESSIN, L. J. 1925. An ecological study of the polypody fern Polypodium polypodioides as an epiphyte epiphyte (ĕp`əfīt') or air plant, any plant that does not normally root in the soil but grows upon another living plant while remaining independent of it except for support (thus differing from a parasite). in Mississippi. Ecology 6:17-38. PICKETT, F. 1931. Notes on xerophytic ferns. Amer. Fern J. 21:49-57. PICKETT, F. and M. E. MANUEL. 1926. An ecological study of certain ferns: Pellaea atropurpurea (L.) Link. and Pellaea glabella glabella /gla·bel·la/ (glah-bel´ah) the area on the frontal bone above the nasion and between the eyebrows. gla·bel·la n. pl. gla·bel·lae 1. Mett. Bull. Torrey Bot. Club 53:1-5. PROCTOR, M. C. F. 2003. Comparative ecophysiological measurements on the light responses, water relations and desiccation tolerance of the filmy ferns Hymenophyllum wilsonii Hiik. and H. tunbrigense (L.) Smith. Ann. Bot. 91:717-727. PROCTOR, M. C. F. and V. C. PENCE. 2002. Vegetative tissues: bryophytes, vascular plants and vegetative propagules. Pp. 207-237, in M. Black and H. W. Pritchard, eds. Desiccation and survival in plants: drying without dying. CABI Publishing, Wallingford, UK. PROCTOR, M. C. F. and Z. TUBA. 2002. Poikilohydry and homoihydry: antithesis or spectrum of possibilities? New Phytologist 156:327-349. QUIRK, H. and T. C. CHAMBERS. 1981. Drought tolerance Drought tolerance refers to the degree to which a plant is adapted to arid or drought conditions. Desiccation tolerance is an extreme degree of drought tolerance.[1] Plants naturally adapted to dry conditions are called xerophytes. in Cheilanthes with special reference to the gametophyte gametophyte (gəmē`təfīt'), phase of plant life cycles in which the gametes, i.e., egg and sperm, are produced. The gametophyte is haploid, that is, each cell contains a single complete set of chromosomes, and arises from the . Fern Gazette 12:121-129. ROUSCHAL, E. 1938. Eine physikalische Studie an Ceterach officinarum Willd. Flora 32:234-252. SCHNEIDER, H., E. SCHUETTPELZ, K. M. PRYER pry·er n. Variant of prier. , R. CRANFILL, S. MAGALLON and R. LUPIA. 2004. Ferns diversified in the shadow of angiosperms. Nature 428:553-557. SMITH, A. R., K. M. PRYER, E. SCHUETTPELZ, P. KORALL, H. SCHNEIDER and P. G. WOLF. 2006. A classification for extant ferns. Taxon 55:705-731. STUART, T. S. 1968. Revival of respiration and photosynthesis in dried leaves of Polypodium polypodioides. Planta 83:185-206. MICHAEL KESSLER Michael Kessler (* 24 June 1967 in Wiesbaden, Germany) is a German actor, comedian and author. Theater After his acting training at Westfälische Schauspielschule Bochum from 1988 to 1992 Michael Kessler had roles at the following theaters: Schauspielhaus Bochum, and YVONNE SIORAK Albrecht-von-Haller-Institut fur Pflanzenwissenschaften, Abt. Systematische Botanik, Untere Karspule 2, D-37073 Gottingen, Germany
TABLE 1. Several plant adaptive strategies to counter drought stress,
and their representation among pteridophytes (modified from Levitt,
1958; Benzing, 1990; Losch, 2001). The five lower categories together
form the group of homoiohydric strategies.
Morphological and Reaction of leaves
Strategy phenological characters to desiccation
Poikilohydric leaves dry out under rapid; leaves roll up;
water stress and up to 95% water loss
rehydrate when water possible without
is available, often lethal effects
densely scaly
Mesomorphic leaves of intermediate rapid; leaves wither
thickness, soft to strongly and develop
hard, sensitive to necroses after slight
desiccation; no special water loss
adaptations to drought
stress
Xeromorphic leaves thick, hard, slow; leaves maintain
narrow, often their shape and
longitudinally folded thickness; survive
or rolled, with moderate water loss
abundant sclerenchyma;
leaf surfaces
with a waxy cover;
stomata abundant,
sunken into the leaf
surfaces; venation
density high
Succulent leaves or rhizomes slow; leaves become
thick and spongy, thinner as they
strongly change dry out and survive
their thickness in high water loss
response to hydration
status
Drought- leaves, pinnae, or rapid to intermediate;
deciduous pinnules are shed in leaves, pinnae, or
the dry season, thin pinnules are shed
to medium thickness under water stress
Impounding leaves arranged in a unknown
funnel; water is not
impounded directly
as in bromeliads,
but mostly stored in
accumulated organic
material
Reaction of leaves Fern taxa
Strategy to rehydration (examples)
Poikilohydric rapid full recovery; cheilanthoids,
water uptake through Hymenophyllum,
leaf surfaces Pleopeltis and
allies, some
Selaginella
Mesomorphic slow; water content most ferns
does not or very
slowly recover to
original levels
Xeromorphic slow; water uptake some Asplenium,
mostly through roots Campyloneurum,
some Elaphoglossum,
Niphidium, some
Polypodium
Succulent slow through leaves; Lemmaphyllum,
water uptake mostly Pyrrosia
through roots
Drought- unknown some Adiantum,
deciduous Nephrolepis,
Phlebodium
Impounding unknown some Asplenium
TABLE 2. Desiccation resistance, desiccation delay, and recuperation
capacity of excised leaves from 43 species of pteridophytes. Letters
in brackets after the names indicate wether whole leaves (L), pinnae
(P), or stem sections (S) were studied.
Desiccation
resistance
Morphological (% water
Species category contents)
Adiantum capillus-veneris L. (L) deciduous 81
Adiantum macrophyllum Sw. (L) intermediate 99
Adiantum trapeziforme L. (L) mesophytic 51
Adiantum villosum L. (L) intermediate 86
Anemia mexicana Klotzsch (L) poikilohydric 74
Anemia rotundifolia Schrad. (L) poikilohydric 86
Anemia tomentoso (Sav.) Sw. (L) poikilohydric 99
Asplenium bulbiferum G. Forst. (L) xerophytic 73
Asplenium daucifolium Lam. (L) intermediate 86
Asplenium dimorphum Kunze (L) intermediate 65
Asplenium mannii Hook. (L) mesophytic 30
Asplenium marinum L. (L) intermediate 81
Asplenium nidus L. (L) impounding 58
Asplenium rutaefolium Kunze (L) intermediate 75
Asplenium salicifolium L. (L) intermediate 80
Blechnum brasiliense Desv. (P) mesophytic 47
Blechnum cordatum (Desv.) Hieron. (P) mesophytic 59
Blechnum occidentale L. (L) mesophytic 68
Blechnum spicant (L.) Roth (L) intermediate 81
Campyloneurum xalapense F6e (L) xerophytic 81
Cheilanthes myriophylla Desv. (L) poikilohydric 99
Cheilanthes notholaenoides poikilohydric 85
(Desv.) Maxon ex Weath. (L)
Elaphoglossum apodum mesophytic 60
(Kaulf.) Schott ex J. Sm. (L)
Elaphoglossum crinitum (L.) Christ (L) mesophytic 63
Elaphoglossum engelii (Karst.) Christ (L) xerophytic 44
Elaphoglossum erinaceum (Fee) T. 74
Moore (L) mesophytic
Elaphoglossum latifolium (Sw.) J. Sm. (L) intermediate 74
Hemionitis arifolia (Burm.) T. Moore (L) poikilohydric 96
Hemionitis palmata L. (L) poikilohydric 96
Microgramma piloselloides (L.) Copel. (L) poikilohydric 95
Pecluma eurybasis (C. Chr.) M.G. 91
Price (L) poikilohydric
Pellaea sagittata (Cav.) Link (L) deciduous 72
Polypodium australe F6e (L) intermediate 91
Polypodium scouleri Hook & Grev. (L) xerophytic 70
Polystichum lachenense (Hook.) Bedd. (P) intermediate 89
Polystichum platyphyllum (Willd.) mesophytic 74
C. Presl (P)
Pteris quadriaurita Retz. (P) mesophytic 46
Selaginella geniculata mesophytic 86
(C. Presl) Spring (S)
Selaginella helvetica (L.) Link (S) poikilohydric 99
Selaginella martinensii Spring. (S) mesophytic 67
Selaginella rotundifolia Spring. (S) mesophytic 88
Selaginella trisulcata Aspl. (S) poikilohydric 90
Selaginella vogelii Spring. (S) mesophytic 69
Desiccation capacity
delay (% water
Species (hours) contents)
Adiantum capillus-veneris L. (L) 2 87
Adiantum macrophyllum Sw. (L) 4 59
Adiantum trapeziforme L. (L) 2 84
Adiantum villosum L. (L) 3 100
Anemia mexicana Klotzsch (L) 2 75
Anemia rotundifolia Schrad. (L) 3 90
Anemia tomentoso (Sav.) Sw. (L) 4 67
Asplenium bulbiferum G. Forst. (L) 6 84
Asplenium daucifolium Lam. (L) 6 54
Asplenium dimorphum Kunze (L) 6 78
Asplenium mannii Hook. (L) 1 82
Asplenium marinum L. (L) 3 76
Asplenium nidus L. (L) 7 57
Asplenium rutaefolium Kunze (L) 5 80
Asplenium salicifolium L. (L) 7 68
Blechnum brasiliense Desv. (P) 2 86
Blechnum cordatum (Desv.) Hieron. (P) 1 90
Blechnum occidentale L. (L) 1 96
Blechnum spicant (L.) Roth (L) 4 55
Campyloneurum xalapense F6e (L) 7 74
Cheilanthes myriophylla Desv. (L) 6 38
Cheilanthes notholaenoides 5 96
(Desv.) Maxon ex Weath. (L)
Elaphoglossum apodum 4 59
(Kaulf.) Schott ex J. Sm. (L)
Elaphoglossum crinitum (L.) Christ (L) 2 49
Elaphoglossum engelii (Karst.) Christ (L) 7 75
Elaphoglossum erinaceum (Fee) T. 2 66
Moore (L)
Elaphoglossum latifolium (Sw.) J. Sm. (L) 6 49
Hemionitis arifolia (Burm.) T. Moore (L) 4 75
Hemionitis palmata L. (L) 13 91
Microgramma piloselloides (L.) Copel. (L) 6 35
Pecluma eurybasis (C. Chr.) M.G. 4 80
Price (L)
Pellaea sagittata (Cav.) Link (L) 1 64
Polypodium australe F6e (L) 6 47
Polypodium scouleri Hook & Grev. (L) 36 49
Polystichum lachenense (Hook.) Bedd. (P) 2 100
Polystichum platyphyllum (Willd.) 4 72
C. Presl (P)
Pteris quadriaurita Retz. (P) 2 99
Selaginella geniculata 3 83
(C. Presl) Spring (S)
Selaginella helvetica (L.) Link (S) 2 63
Selaginella martinensii Spring. (S) 2 93
Selaginella rotundifolia Spring. (S) 2 56
Selaginella trisulcata Aspl. (S) 4 58
Selaginella vogelii Spring. (S) 1 86
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