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In this work, the author offers a valid description of the basalt scree slope stones-grassland (Geranio rotundifolio-Sedetum albi Jakucs ex Soó 1973), whose depiction used to be incomplete. The author publishes 15 relevés of the association concerning the basalt volcanic hills of the northern Transdanubian (Hungary) region - characterised by distinctive flora and vegetation -, determines the characteristic features, habitat conditions as well as geographical distribution of the association. Column 2 of Table 2 has been selected as the neotype relevé of the association.

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Naturalization is the introduction and establishment of a nonnative species with sustainable populations in a novel environment. The success of nonnative species may be influenced by their relatedness to the native flora. Darwin proposed that if a nonnative plant species is introduced into an environment without native congeners, the nonnative species will have a greater chance of becoming naturalized. To test Darwin’s naturalization hypothesis, we compiled a Kentucky plant database consisting of 821 vascular plant species and subsequently selected species traits and distribution information to determine the effect of congeneric species and traits on the probability of successful naturalization and invasion. The predictors used include reproductive traits, growth form, abundance, habitat type, native congeners, and biogeographical origin. We fit three sets of generalized linear mixed models (GLMMs) with a binomial family and a logit link. Backward selection based on minimizing the Akaike Information Criterion (AIC) was used in the analyses. Our results from these three sets of models clearly indicate that the validity of Darwin’s hypothesis is invasion stage dependent. More specific, the naturalized and invasive models (predicting the probability of being naturalized and invasive respectively) did not support Darwin’s naturalization hypothesis. The number of native congeners had no effect on the likelihood that a particular species would naturalize and become invasive. Our results suggest that Darwin’s naturalization hypothesis is more relevant during the early stage of establishment as demonstrated by the native model (predicting the probability of being native) and it becomes irrelevant during the late stages of invasion as indicated by the naturalized and invasive models. Thus, it can be generalized that biotic interactions, especially competition, is a critical determinant of initial success for nonnative species in the recipient communities. Once established, the fate of non-native species during the late stages of invasion may be more related to other factors such as biogeographic origin and habitat conditions. Furthermore, we found reproductive traits such as flowering phenology and flower type are associated with invasion success. We also recognized contrasting traits between native and nonnative species, indicating niche differentiation between these two groups of species. Niche overlapping was found as well among species regardless of the status of being native or otherwise. Our study provides a novel approach to advance the understanding of phylogenetic relatedness between nonnative species and native flora by integrating traits and niche concepts at the regional scale.

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In a comparative study, a relatively simple and high sensitivity method was developed for analysis of testosterone-equivalent(s) in the faeces of different bird species. To determine the recovery of extractions and purifications, tritium-labelled testosterone was added to the wet samples. Then the samples were treated with sodium dodecil sulphate (SDS), an emulsificator to “open-up” the complex, lipid-coated particles of faecal samples. This emulsification resulted in the decrease of the quantity of interfering substances after diethyl-ether extraction and the linearity of the measured testosterone equivalents from aliquots in the range of 2 and 10 mg of faeces. In the RIA, we applied a group specific polyclonal testosterone antibody which cross-reacted with reduced metabolites and at a certain level with sulphate conjugates as well. The use of Helix enzymes did not modified significantly the results of the analysis relating to a low level of conjugated androgens in the faecal extracts. The biological validity of the method was tested on domestic cockerels, where between the plasma and faecal testosterone values a four hours phase shift was observed, with a correlation of 0.6355. This method is suitable for “non invasive”, behavioural-ethological studies.

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We studied the vegetation of 54 sandy old-fields abandoned at different times. We first surveyed the vegetation in 1998 and developed predictions about the spontaneous succession using the chronosequence approach. Afterwards, we repeated the survey in 2000, 2001, 2002 and 2003, and based on this monitoring we tested the predictions of the chronosequence study. For both approaches, we analysed the changes in functional group composition during succession. According to the chronosequence study, the most important changes occurred in the youngest old-fields, abandoned 1–4 years ago: the species number and abundance of annuals, disturbance-requiring and anthropogenic species decreased, and those of perennials, grassland generalists, and species with low disturbance-tolerance increased. No changes were predicted for the older fields. The monitoring confirmed the predictions for the youngest old-fields. However, during the 5 years of monitoring several functional groups changed in their species number or abundance even on the older abandoned fields. Both of the methods showed that secondary succession on sandy old-fields is relatively fast. The chronosequence study provided a more static view of the processes, while the multi-year monitoring revealed that there were considerable inter-annual changes as well. With the yearly monitoring we can detect the effect of additional factors, such as land use changes (e.g., changes in grazing intensity) and yearly climate fluctuations on the direction and rate of secondary succession.

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Cereal Research Communications
Authors: L. Błaszczyk, I. Kramer, F. Ordon, J. Chełkowski, M. Tyrka, G. Vida, and I. Karsai

The set of 44 near-isogenic lines of spring wheat cv. Thatcher and wheat genotypes known to carry specific leaf rust resistance genes were included in the present study for the preliminary validation of twelve STS and SCAR markers linked to leaf rust resistance genes Lr9, Lr19, Lr20, Lr21, Lr24, Lr25, Lr26, Lr28, Lr29, Lr37 . Seven Lr genes were specifically tagged by STS and SCAR markers. The presence of genes Lr9, Lr19, Lr20, Lr24, Lr28, Lr29, Lr37 in the tested plant materials was confirmed by a unique amplification of markers SCS5 550 , SCS265 512 and SCS253 736 , STS638, SCS73 719 , SCS421 570 , IPY10 and Lr29F24/R24, cslVrgal3, PS10R/L, respectively. Evaluation of the repeatability and the reliability of selected markers (pTAG621 for Lr1 , STS683 for Lr20 , D14L for Lr21 , Lr25F20/R19 for Lr25 , Lr29F24/R24, IPY10 for Lr29 , cslVrgal3 for Lr37 and PS10R/L for Lr47 ) across four European laboratories and PCR conditions demonstrated the usability of STS638, Lr29F24/R24, IPY10, cslVrgal3 and PS10R/L markers in marker-assisted selection. STS markers pTAG621 for gene Lr1 , D14L for gene Lr21 , Lr25F20/R19 for gene Lr25 were found to be unsuitable for effective screening of large segregating populations in breeding programs.

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215 type specimens of 38 Sorbus taxa (15 holotypes, 23 lectotypes and 177 other types) described by Sándor Jávorka, Ádám Boros and Zoltán Kárpáti from the Carpathian Basin and the Carpathians have been examined. Types are designated here, and 15 names validly published.

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Testing the ecological communities of different areas for convergence, in the sense of remarkable similarity in the characteristics of the species present, has a long history in biology. Recently, numerical methods have been developed for comparing community-level convergence to an explicit null model. No valid method has been known for testing the significance of texture convergence when the species are weighted by their abundance. Six combinations of method variants are tested on random datasets. A valid P value (i. e., with P . 0. 05 in no more than 5% of the cases) is obtained so long as for each species the distribution of abundances across sites is retained, and only the assignment of character values is randomised. Further restriction is not necessary for obtaining a valid P value, and can lead to a test with considerably lower power to detect convergence. The power of the test with free matching of character values to species is only moderate with 10 sites, though improved with larger numbers of sites. Previous methods for detecting texture convergence have examined convergence only in the mean value for any character. It is possible that the external environment might be reflected in the community mean of a character, leaving the imprint of convergence on the shape of the distribution, rather than the mean. A method for comparing the shape is described, and it is shown that the null model is valid also for this test statistic.  

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Estudios Sobre Rubiáceas Mexicanas XII

El género Mitracarpus Zucc. ex Schult. et Schult. f. (Spermacoceae) en México

Acta Botanica Hungarica
Authors: A. Borhidi and L. Lozada

The authors working on the Rubiaceae flora of the state Guerrero and that of Mexico found a higher richness of diversity in the genus Mitracarpus than it was formerly registered. They describe 6 new species: M. aristatus and M. trichanthus from Sinaloa, M. floribundus from Baja California, M. capitatus and M. falcatus from Guerrero y M. carnosus from Oaxaca. In their treatment Mexico has not less than 13 species of Mitracarpus; M. breviflorus A. Gray and M. glabrescens are valid species and M. rhadinophyllus proved to be a new synonym of M. linearifolius A. Rich.

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Community Ecology
Authors: M. Marignani, C. Ricotta, F. Rossi, A. Pavesi, and G.C. Avena

Subtaxon-to-taxon ratios such as the species-to-genus ratio have been frequently used in ecology and biogeography despite their well-known sample size dependence. For instance, any subtaxon-to-taxon ratio is an increasing function of the area sampled. Hence, its validity as an ecological indicator is problematic at best. This drawback can be avoided by constructing taxon-subtaxon curves. Owing to their scale-free nature, taxon-subtaxon curves standardize the information in subtaxon-to-taxon ratios allowing for meaningful comparison of datasets.

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Estudios Sobre Rubiáceas Mexicanas, XL

Tres nuevas especies del género Bouvardia Salisb. y la revalidación de una especie omisa de Centroamérica

Acta Botanica Hungarica
Authors: A. Borhidi, E. Martínez-Salas, and S. Salas-Morales

Three new species belonging to the Bouvardia genus are recognised and described by the authors of the paper. B. lancifolia Borhidi et Salas-Morales of Oaxaca from the relationship of B. rosea Schltdl. of Central Mexico, the B. sinaloae Borhidi et E. Martínez Salas of Sinaloa, related to the B. sancaroli Borhidi et M. Martínez-Díaz of Tamaulipas and the B. tenuis Borhidi et Salas-Morales of Oaxaca related to the B. rzedowskii Terrell et S. D. Koch of Guerrero and Oaxaca proved to be new for science. Detailed studies of floral characters led to confirm the correct circumscription of the Bouvardia bouvardioides (Seem.) Standl. and its separation from the B. pallida Standl., a definitely valid species for the Mesoamerican flora, living in Guatemala and San Salvador. Consequently, B. bouvardioides has to be considered as an endemic of Central Mexico.

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