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1

Sur la multiplication de Centropyxis discoides et l'influence du milieu sur la morphologie de la theque (Rhizopoda testacea)

100%
Chardez D.
Acta Protozoologica
|
1989
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tom 28
|
nr 1
2

Plant functional trait response to habitat change and grazing in a semiarid grassland: unravelling species turnover and intraspecific variation effects

100%
Zhang J., Zuo X., Lv P., Zhao S., Zhao X.
Polish Journal of Ecology
|
2019
|
tom 67
|
nr 1
Plant community assembly is determined by species turnover and intraspecific trait variations (ITV) controlled by environment changes. However, little is known about how species turnover and ITV affect the responses of plant community to habitat changes and grazing disturbance in semiarid grasslands. Here, we measured five functional plant traits in four typical grassland habitats under fencing and grazing disturbance in a semiarid grassland, Northern China, including plant height, specific leaf area (SLA), leaf dry matter content (LDMC), leaf nitrogen content (LNC) and leaf carbon: nitrogen ratio (C:N). We also calculated the community weighted means (CWM) and non-weighted means (CM) of all traits and examined the relative roles of species turnover and ITV in affecting the responses of community traits to habitat changes and grazing disturbance. Our results showed that the CWM and CM values of five functional traits differed with grassland habitat changes. As compared to other grasslands, the Stipa steppe had the higher plant height, the sandy grassland had the higher SLA and lower LDMC, and the meadow had the lower LNC and higher C:N. Grazing decreased plant height across grassland habitats, as well as decreased SLA and increased LDMC in meadow. The responses of all community-level traits to habitat changes were driven by species turnover, while the responses of phenotypic traits (height, SLA and LDMC) to grazing were determined by both species turnover and ITV. So, we argue that ITV should be considered when understanding plant community assembly under grazing disturbance regime in semiarid grasslands.
3

Ecological strategy at cell size level to respond to stressed environments

84%
Wang H., Liu Y., Chen H.
Polish Journal of Ecology
|
2016
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tom 64
|
nr 2
The cell size variations in woody plants in various environments are not well known, and the underlying mechanism has not been fully analyzed. 2. The current study focused on the intraspecific and interspecific size variations in palisade cells occurring in 76 woody species along an elevation gradient (1800–4500 m a.s.l.) on Gongga Montain (1400–7552 m a.s.l.) in southwest China, which included tropical and subtropical genera of broad-leaved forest flora including Salix hyperba as the species occurring on all elevations. We hypothesized that cell size is regulated by alterations in width-length scaling (L-D ratio) to mediate a surface-to-volume ratio (S/V) most suitable for the prevailing environmental conditions. 3. It was observed that cell size co-varied similarly with environmental conditions at the conspecifics, congenerics, and interspecifics levels investigated. Cell sizes decreased among conspecifics, or increase among congenerics and interspecifics via negative or positive scaling of width-length ratio at the cellular level. However, this dichotomously differing tendency may be ecologically constrained by both a cost-increasing and benefit-diminishing mechanism of cell dimension with increasing elevation at the species level, implying a ‘middle way’ strategy for species to stressed environments. 4. The implications of the results for regional floristic evolution are discussed.
4

Genome size variation of Lotus peregrinus at evolution canyon I microsite, Lower Nahal Oren, Mt. Carmel, Israel

84%
Gasmanova N., Lebeda A., Dolezalova I., Cohen T., Pavlicek T., Fahima T., Nevo E.
Acta Biologica Cracoviensia. Series Botanica
|
2007
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tom 49
|
nr 1
39-46
On the basis of previous studies showing a positive correlation between number of copies of retrotransposons and geographical environment, we hypothesized that different ecogeographical conditions on opposite slopes of Evolution Canyon I could cause intraspecific variation in plant genome size. To test this hypothesis, we chose Lotus peregrinus L. (annual, self-pollinator) as the first candidate because of its biological contrast to the previously studied carob tree (long-lived, cross-pollinator). Absolute nuclear DNA content of 60 genotypes of L. peregrinus was estimated by PI flow cytometry, with tomato (Lycopersicon esculentum cv. Stupicke) as internal reference standard. The mean 2C-value in L. peregrinus was 2.546 pg, ranging from 2.39 pg to 2.71 pg. The mean 2C-value was higher in plants from the south-facing slope (2.549 pg) than from the north-facing slope (2.544 pg), but we were not able to show significant interslope differences in genome size.
5

Prochristianella clarkeae Beveridge, 1990 (Eutetrarhynchidae): a species complex or a species with intraspecific variation in the distribution of its tegumental microtriches?

84%
Salmani S., Haseli M.
Acta Parasitologica
|
2017
|
tom 62
|
nr 1
6

Taxonomic study on the genus Pselaphodes Westwood (Coleoptera: Staphylinidae: Pselaphinae) from China. Part II

84%
Yin Z.-W., Li L.-Z., Zhao M.-J.
Annales Zoologici
|
2011
|
tom 61
|
nr 3
This is the second paper of a series dealing with the Chinese fauna of the large genus Pselaphodes Westwood, 1870. Twelve new species and a new synonym are presented: P. bomiensis sp. nov. (Xizang); P. biwenxuani sp. nov. (Xizang); P. condylus sp. nov. (Guizhou); P. cuonaus sp. nov. (Xizang); P. fengtingae sp. nov. (Zhejiang); P.gongshanensis sp. nov. (Yunnan); P. hamniensis sp. nov. (Xizang); P. jizushanus sp. nov. (Yunnan); P. meniscus sp. nov. (Sichuan); P. parvus sp. nov. (Guizhou); P.pectinatus sp. nov. (Hainan);P. wuyinus Yin et al., 2010 syn. nov. = P. tianmuensis Yin et al., 2010; and P. yanbini sp. nov. (Guizhou). New distributional data and discussion on intraspecific variations of P. tianmuensis and P. aculeus are provided. An updated key is given to assist in distinguishing all so far known Chinese species of Pselaphodes. A checklist of world species of Pselaphodes is also provided.
7

Favognathus afyonensis sp.nov. with notes on Raphignathus collegiatus Atyeo, Baker et Crossley, 1961 [Acari: Raphignathoidea] from Turkey

84%
Koc K., Akyol M.
Annales Zoologici
|
2004
|
tom 54
|
nr 2
A new species of cryptognathid mite Favognathus afyonensis sp. nov. is described and illustrated from Turkey. Intraspecific variations of Raphignathus collegiatus Atyeo, Baker et Crossley, 1961, a new record for Turkey, are also reported.
8

RAPD analysis of somaclonal and natural DNA variation in Hypericum perforatum L.

84%
Haluskova J., Kosuth J.
Acta Biologica Cracoviensia. Series Botanica
|
2003
|
tom 45
|
nr 2
RAPD analysis of DNA variation in somaclones of Hypericum perforatum which passed through one or two cycles of in vitro regeneration revealed great variation among the donor plants from which the somaclones were regenerated. The donor plants represented either seed-derived plants or the seed progeny of first-cycle somaclones. The variation among them may indicate natural genetic variation in Hypericum perforatum. In addition, no differences were found in the RAPD profiles of 51 first-cycle somaclones within groups originated from 7 donor plants. This may point to relative stability of the Hypericum perforatum genome under given conditions of in vitro regeneration. One polymorphic band was found in 3 of 51 RAPD profiles of second-cycle somaclones, perhaps an effect of repeated in vitro regeneration on DNA changes. Study of DNA variation among 75 Hypericum perforatum progenies derived from 8 mother plants indicates the prevalence of the apomictic mode of reproduction. Analysis of 47 seed progenies of diploid somaclones derived from 5 R3 plants may suggest the sexual mode of reproduction.
9
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The variability of reed [Phragmites australis [Cav.] Trin. ex Steud. [Poaceae]] populations expressed in morphological traits of panicles

84%
Krzakowa M., Kolodziejczak M., Drapikowska M., Jakubiak H.
Acta Societatis Botanicorum Poloniae
|
2003
|
tom 72
|
nr 2
Using a transect technique, each of 12 reed Phragmites australis (Cav.) Trin ex Steud. populations collected in middle part of Odra River-basin, represented by more than 30 plants, were compared with 3 populations from other part of the country and 1 from France. Each panicle was examined according to 15 morphological traits. Results of measurements were subjected to multivariate analysis of variance, to analysis of canonical variables and used for construction of a minimum spanning tree (= dendrite) on the basis of the shortest Mahalanobis distances. The obtained results indicate that populations are generally similar. One population from France (Orleans) shows visible separateness. It may suggest that morphological traits of panicles may be useful in investigations of the reed P. australis populations of a larger geographical distribution.
10

Altitudinal variation in the diet of sika deer on the Izu Peninsula: patterns in the transitional zone of geographic variation along the Japanese archipelago

67%
Kitamura T., Sato Y., Takatsuki S.
Acta Theriologica
|
2010
|
tom 55
|
nr 1
89-93
Geographical variation in the diet of sika deer Cervus nippon Temminck, 1838 has been well characterised: northern populations are grazers, whereas southern deer are browsers. This variation largely reflects genetic-based differences in morphology. However, environmental factors would be also important. If a same genetic population live in different habitats, we can check altitudinal shifts in sika deer food consumption. We hypothesised that changes in the diet of the sika deer population on the Izu Peninsula, which is located within the transitional zone of resource (vegetation) variation and encompasses a broad altitudinal range, would mirror shifts in the composition of vegetation. Analyses of the rumen contents of the deer population indicated that dwarf bamboo accounted for 10.5, 46.2, and 74.3% of the deer diet in the low (<800 m), middle (800–1000 m), and high (>1000 m) altitudinal zones, respectively. In contrast, evergreen broad-leaved species accounted for 35.7, 23.1, and 5.9%, respectively. These results suggest that the diet of sika deer is more strongly affected by environmental factors, such as plant community composition, than by genetic factors.
11

Mitochondrial cytochrome b sequences resolve the taxonomy of field mice (Apodemus) in the western Balkan refugium

67%
Krystufek B., Luznik M., Buzan E. V.
Acta Theriologica
|
2012
|
tom 57
|
nr 1
Apodemus sylvaticus stankovici, described from the topographically rough landscape of the western Balkan glacial refugium, was recently proposed as being either a junior synonym of Apodemus flavicollis or a species on its own right. To untangle this taxonomic vagueness, we sequenced complete cytochrome b gene in 28 field mice collected at 12 locations in the mountains of Bosnia and Herzegovina, Montenegro, western Macedonia and northern Greece. Samples yielded 27 new haplotypes which clustered into two distinct groups. One of these clades also included the reference haplotype of A. flavicollis, while another cluster emerged as being identical with the reference sample for A. sylvaticus. As is common in Apodemus, both species retrieved in our analysis were characterized by low levels of intraspecific variation (0.4–0.9%) as opposed to a high level of differentiation between them (8.0–10.0%); therefore, the taxonomic classification of our material was without doubt. We found no evidence regarding the presence of an additional cryptic species in the mountains of the western Balkans. The very similar values of genetic variability in the two species imply their common evolutionary history of a long-term coexistence in the western Balkan refugium.
12

High variability of nuclear DNA content in cultivars and natural populations of Poa pratensis L. in relation to morphological characters

67%
Murovec J., Kastelec D., Vilhar B., Cop J., Bohanec B.
Acta Biologica Cracoviensia. Series Botanica
|
2009
|
tom 51
|
nr 2
45-52
Kentucky bluegrass is a facultative apomict which is propagated from seeds of variable genetic origins, ploidy levels and nuclear DNA contents. This study analyzes the variability of relative nuclear DNA content among cultivars and natural populations, and examines whether this variability is correlated with morphological traits. Relative nuclear DNA content (an indirect measure of chromosomal variability) was determined in 281 plants from 28 accessions (17 cultivars, 11 populations) using flow cytometry of DAPI-stained nuclei. The same plants were also measured for leaf area and stomatal length. Variation of measured relative DNA content between the studied accessions was very high (5.5-fold). Intra-accession variation was very high in six accessions, even though three of these were cultivars. Relative nuclear DNA content was correlated with stomatal length but not with leaf area. The lack of correlation with leaf area might explain why high intra-accession variability of nuclear DNA content was found in released cultivars that had passed uniformity testing during the registration procedure. We suggest that nuclear DNA content measurement should be made part of the cultivar registration process
13

The causes of intraspecific variation in sexual dimorphism in the common grass snake populations, Natrix natrix LINNAEUS, 1758 (Serpentes, Colubridae): Data from the South Western Poland

67%
Borczyk B.
Acta Zoologica Cracoviensia. Ser.A Vertebrata
|
2007
|
tom 50A
|
nr 1-2
14

Intraspecific variation of diagnostic rDNA genes in Paramecium dodecaurelia, P. tredecaurelia and P. quadecaurelia [Ciliophora: Oligohymenophorea]

67%
Tarcz S., Przybos E., Prajer M., Greczek-Stachura M.
Acta Protozoologica
|
2006
|
tom 45
|
nr 3
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