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Species delimitation and inter-specific gene flow in Tamarix L. (Tamaricaceae)

Abstract

Tamarix L. play important role in preventing deforestation in Iran. Tamarix species exhibit wide range of morphological variation therefore, the species delimitation become difficult. This is further complicated due to similarity of morphological characters in closely related species and the occurrence of inter-specific hybridization. The present study was performed to identify Tamarix species and their potential hybrids in Semnan Province of Iran. We used ITS and ISSR and 42 morphological characters for our investigation. Molecular phylogeny of the studied species and their relationship was not in agreement with the species tree of morphological characters and with taxonomic treatment of the genus. HGT tree of ITS and morphological data obtained revealed the occurrence of inter-specific hybridization or introgression between Tamarix species.

Open access
Summer fire in steppe habitats: long-term effects on vegetation and autumnal assemblages of cursorial arthropods

Abstract

Being an essential driving factor in dry grassland ecosystems, uncontrolled fires can cause damage to isolated natural areas. We investigated a case of a small-scale mid-summer fire in an abandoned steppe pasture in northeastern Ukraine and focused on the post-fire recovery of arthropod assemblages (mainly spiders and beetles) and vegetation pattern. The living cover of vascular plants recovered in a year, while the cover of mosses and litter remained sparse for four years. The burnt site was colonised by mobile arthropods occurring in surrounding grasslands. The fire had no significant impact on arthropod diversity or abundance, but changed their assemblage structure, namely dominant complexes and trophic guild ratio. The proportion of phytophages reduced, while that of omnivores increased. The fire destroyed the variety of the arthropod assemblages created by the patchiness of vegetation cover. In the post-fire stage they were more similar to each other than at the burnt plot in the pre- and post-fire period. Spider assemblages tended to recover their pre-fire state, while beetle assemblages retained significant differences during the entire study period.

Open access
The tribe Scrophularieae (Scrophulariaceae): A Review of Phylogenetic Studies

Abstract

Molecular data have been increasingly used to study the phylogenetic relationships among many taxa, including scrophs. Sometimes they have provided phylogenetic reconstructions that are in conflict with morphological data leading to a re-evaluation of long-standing evolutionary hypotheses. In this paper, we review reports of the recent knowledge of the phylogenetic relationships within Scrophularieae (2011–2017). The results of these analyses led to the following conclusions. (1) Species of Scrophularia have undergone one or more Miocene migration events occurred from eastern Asia to the North America with subsequent long dispersal and diversification in three main directions. (2) Allopolyploid and aneuploid hybrid speciation between Scrophularia species can occur, so hybridization and polyploidy have an important role for history of diversification. (3) The ancestral staminode type for the genus Scrophularia seems to be a large staminode. (4) Monophyly of the genus Verbascum with respect to the genus Scrophularia is strongly supported. (5) Oreosolen, is not monophyletic, because all accessions of Oreosolen were nested within Scrophularia. We discuss methods of data collection and analysis, and we describe the areas of conflict and agreement between molecular phylogenies.

Open access
Bio-chemical properties and susceptibility to fire blight (Erwinia amylovora Burrill) of scab-resistant apple cultivars (Malus domestica Borkh.)

Abstract

The focus of our research was to evaluate different apples cultivars in terms of their biological properties and bioactive compounds content, and determine the levels of their resistance (or susceptibility) to fire blight. The properties of 10 scab-resistant apple cultivars were examined on the Žiča monastery estate (West Serbia) during the period from 2011 to 2015. The biological and chemical properties such as firmness, maturity stage, total soluble solids, total acids, total and reducing sugars, ascorbic acid content and surface blush of apple fruits were monitored. Various phenolic compounds in the tested samples were tentatively identified by LC-MS analyses. A study of generative properties included: number of flower buds, fruit mass and width, crop load, yield efficiency and yield. During the period of blooming and intensive shoot growth, artificial inoculations were carried out. For each cultivar, a fire blight score was determined by dividing the average length of necrotic tissue by the average total shoot length. In the study period, the cultivars ‘GoldRush’ (41.1 t ha−1) and ‘Florina’ (35.9 t ha−1) produced the highest yields, and the cultivars ‘Discovery’ (19.0 t ha−1) and Selection 25/63 (15.1 t ha−1) the lowest. The cultivar ‘William’s Pride’ produced the largest fruits, with an average fruit mass of 206.8 g. The earliest harvest period was recorded for the cultivar ‘Discovery’ (end of July), and the latest for the cultivar ‘GoldRush’ (beginning of October). The cultivar ‘Enterprise’ had the highest value of total phenols (432.2 mg 100 g−1 FW), while the cultivar ‘Topaz’ had the highest value of total flavanols (145.2 mg 100 g−1 FW). The highest degree of susceptibility to fire blight was found in Selection 25/63, and the greatest resistance was manifested by the cultivar ‘GoldRush’. In the five-year study period, the cultivars ‘GoldRush’, ‘Rewena’ and ‘Enterprise’ exhibited better bio-chemical properties and higher levels of resistance to fire blight than the remaining cultivars.

Open access
An assessment of the local empowerment and environmental management programme (LEEMP) for poverty alleviation in Oyo State, Nigeria

Abstract

Efforts to liberate the populace, most especially rural communities, from the shackles of poverty, have been ongoing through several approaches since the independent era in Nigeria. The most recent is the Local Empowerment and Environmental Management Programme (LEEMP) which is tailored to undertake projects capable of alleviating poverty. This study assessed the LEEMP projects in Itesiwaju Local Government Area of Oyo State in Nigeria. Data collection methods were through a questionnaire survey and an interview. A random sampling technique was employed to sample 152 residents from the study population of 30,400 and the results were analysed using both descriptive and inferential statistics. A binary logistics regression was used to determine the influence of the LEEMP projects on the socio-economic status of residents. The findings revealed that: LEEMP projects were mostly the initiatives of both the community and LEEMP officials (72%); over 80% of the respondents observed that community involvement was mainly about land provision and the labour force, justifying over 70% active involvement of the community in the project execution and maintenance. Inferentially, the prediction model was able to classify 83% of the cases correctly, indicating that the predictors contribute significantly to prediction power of the logistic regression model (p<0.000). The Pseudo R-Square of Cox & Snell’s R-square (28%) and Nagelkerke’s R (42%) also show that the model was relevant in predicting the influence of the LEEMP projects on the residents’ socio-economic status. However, age (p=0.000), household size (p=0.019), average monthly income (p=0.033), and educational status (p=0.038) predictors best contributed to the model prediction. The study, however, recommended among others, that the LEEMP projects should be extended extensively within the country accompanied by an injection of adequate funding and a project monitoring mechanism for continuous functionality and sustainability.

Open access
Cross-Border Comparison of Non-Forest Woody Vegetation in the White Carpathians (Central Europe) Over Last 65 Years

Abstract

Landscape structure is determined by human activities and natural processes. Despite both influences are described in many studies, there remains still question, how the landscape structure reflects the individual socio-economic predictors. To answer this question we compared landscape structure, with emphasis on non-forest woody vegetation, of two states, however, with common socio-economic and political history. Non-forest woody vegetation represents characteristic feature in rural landscape, which increases water retention, biodiversity and bio-migration using green structures. In our study we supposed, that non-forest woody vegetation will have high sensitivity to societal changes and nature conservation measures. On an example of border region in former Czechoslovakia we compared three classes of non-forest woody vegetation (solitaires, patches and linear elements) in three time horizons (1950, 1986, 2011). The most significant differences in spatial structure of non-forest woody vegetation between countries were in the number and area of solitaires, which decreased during the entire period. However, the largest solitaire decrease was in 1950-1986, mainly in correspondence with socialist collective farming. Moreover, the decrease was higher in the Slovak part compared to the Czech part. The primary reason for this was the removal of non-forest woody vegetation on one side and the joining crowns into bigger patches on the other side. The current trend of increasing area of patch and linear elements is related to natural succession. We assume that the main drivers of different development in non-forest woody vegetation in the border region after the split of Czechoslovakia were different management measures applied in nature and landscape conservation and social development.

Open access
Determination of Echinococcus granulosus genotypes in livestock slaughtered in Shush County, Southwest Iran using PCR-RFLP

Summary

Echinococosis is a zoonotic disease caused by the larval stages of Echinococcus spp. that occurs in most parts of the world. Herein, we aimed to evaluate the genotypes of isolated hydatid cysts from slaughtered animals in Shush county, southwestern Iran. Totally, 96 hydatid cysts were collected, including 11 buffaloes, 13 cattle, 12 goat and 60 sheep. The PCR was done by a primer pair (BDI and 4s) to amplify ITS1 fragment. Four restriction endonucleases including AluI, HpaII, RsaI, and TaqI were used for RFLP products and enzymatic reactions were electrophoresed. Finally, twenty PCR products were sent for sequencing and phylogenetic tree was drawn with MEGA6. Molecular identification of 96 hydatid cysts demonstrated a distinctive 1000 bp fragment in all samples from four animal hosts. RFLP analysis showed similar digestion patterns in all samples. AluI digestion yielded 800 bp and 200 bp fragments, HpaII digestion made 700 bp and 300 bp fragments and RsaI digestion entailed 655 and 345segments. Moreover, TaqI rendered no digestion pattern on rDNA-ITS1 region. Additionally, E. granulosus sensu stricto (G1-3 complex) was the prevailing genotype in all livestock samples, according to PCR-RFLP and sequencing analyses.

Open access
Differential sensitivity of myeloid and lymphoid cell populations to apoptosis in peritoneal cavity of mice with model larval Mesocestoides vogae infection

Summary

The metacestode stage of the tapeworm Mesocestoides vogae (M. vogae) has the ability of asexual growth in the peritoneal cavity of rodents and other intermediate hosts without restriction. Early immunological events have decisive role in the establishment of infection. In the present study we investigated the kinetic of myeloid and lymphoid cell populations and the proportions of cells undergoing apoptosis in peritoneal cavities of mice within the first month after oral infection with M. vogae larvae. Proportions of cell phenotypes and apoptotic cells were examined by flow cytometry and by microscopical analysis of cells following May/Grünwald staining and fluorescent stain Hoechst 33234, respectively. Total numbers of peritoneal cells increased and their distribution changed towards accumulation of myelo-monocytic cell lineage in the account of reduced proportions of lymphoid cells. CD4+ T cell subpopulations were more abundant than CD8+ and their proportions elevated within two weeks post infection (p.i.) which was followed by a significant decline. Expression level of CD11c marker on myelo-monocytic cells revealed phenotype heterogeneity and proportions of cells with low and medium expression elevated from day 14 p.i. along with concurrent very low presence of CD11chigh phenotype. Lymphoid cell population was highly resistant to apoptosis but elevated proportions of myeloid cells were in early/late stage of apoptosis. Apoptosis was detected in a higher number of adherent cells from day 14 p.i. onwards as evidenced by nuclear fluorescent staining. By contrast, cells adherent to larvae, mostly macrophages and eosinophils, did not have fragmented nuclei. Our data demonstrated that apoptosis did not account for diminished population of peritoneal lymphoid cells and substantial proportions of myeloid cells seem to be more susceptible to apoptotic turnover in peritoneal cavity of mice with ongoing M. vogae infection, suggesting their important role in the host-parasite interactions.

Open access
The effect of soil on spatial variation of the herbaceous layer modulated by overstorey in an Eastern European poplar-willow forest

Abstract

The tree species composition can influence the dynamics of herbaceous species and enhance the spatial heterogeneity of the soil. But there is very little evidence on how both overstorey structure and soil properties affect the spatial variation of the herb layer. The aim of this study is to evaluate the factors of the soil and overstorey structure by which it is possible to explain the fine-scale variation of herbaceous layer communities in an Eastern European poplar-willow forest. The research was conducted in the “Dnipro-Orils’kiy” Nature Reserve (Ukraine). The research polygon (48°30′51″N, 34°49″02″E) was laid in an Eastern European poplar-willow forest in the floodplain of the River Protich, which is a left inflow of the River Dnipro. The site consists of 7 transects. Each transect was made up of 15 test points. The distance between rows in the site was 3 m. At the site, we established a plot of 45×21 m, with 105 subplots of 3×3 m organized in a regular grid. The adjacent subplots were in close proximity. Vascular plant species lists were recorded at each 3×3 m subplot along with visual estimates of species cover using the nine-degree Braun-Blanquet scale. Within the plot, all woody stems ≥ 1 cm in diameter at breast height were measured and mapped. Dixon’s segregation index was calculated for tree species to quantify their relative spatial mixing. Based on geobotanical descriptions, a phytoindicative assessment of environmental factors according to the Didukh scale was made. The redundancy analysis was used for the analysis of variance in the herbaceous layer species composition. The geographic coordinates of sampling locations were used to generate a set of orthogonal eigenvector-based spatial variables. Two measurements of the overstorey spatial structure were applied: the distances from the nearest tree of each species and the distance based on the evaluation of spatial density of point objects, which are separate trees. In both cases, the distance matrix of sampling locations was calculated, which provided the opportunity to generate eigenvector-based spatial variables. A kernel smoothed intensity function was used to compute the density of the trees’ spatial distribution from the point patterns’ data. Gaussian kernel functions with various bandwidths were used. The coordinates of sampling locations in the space obtained after the conversion of the trees’ spatial distribution densities were used to generate a set of orthogonal eigenvector-based spatial variables, each of them representing a pattern of particular scale within the extent of the bandwidth area structured according to distance and reciprocal placement of the trees. An overall test of random labelling reveals the total nonrandom distribution of the tree stems within the site. The unexplained variation consists of 43.8%. The variation explained solely by soil variables is equal to 15.5%, while the variation explained both by spatial and soil variables is 18.0%. The measure of the overstorey spatial structure, which is based on the evaluation of its density enables us to obtain different estimations depending on the bandwidth. The bandwidth affects the explanatory capacity of the tree stand. A considerable part of the plant community variation explained by soil factors was spatially structured. The orthogonal eigenvector-based spatial variables (dbMEMs) approach can be extended to quantifying the effect of forest structures on the herbaceous layer community. The measure of the overstorey spatial structure, which is based on the evaluation of its density, was very useful in explaining herbaceous layer community variation.

Open access
The effect of the selected remediation medium on the cadmium bioavailability in the selected ecosystem in the Southwestern locality of Slovakia

Abstract

Soil is a sensitive ecological factor. Biodegradable materials from the environment can also be used to deal with serious ecological problems. Soil affecting by remediation medium - garden compost - was analysed for toxic cadmium (Cd) in terms of environmental protection. The objective of this research was to analyse soil and compost at foothill locality of the Tribeč Mountains (Southwestern Slovakia) in the years 2015−2017 to determine Cd contents in soil and compost, pH and to assess Cd bioavailability. The analyses were carried out using the Atomic Absorption Spectrometry with seven-step Selective Sequential Extraction methods. The results obtained were evaluated statistically using the SAS 9.4 software method by Spearman’s correlation coefficient. The results showed that Cd contents in soil had reached 2.96 mg kg−1 and soil with compost (the ratio 1:1) 2.71 mg kg−1 dry matter. Cd contents in the soil exceeded maximum allowed limit of 196%. And deceased by 25% after adding compost. The pH in soil with compost varied from 6.78 to 7.98. The pH prevented the mobility of Cd about 8.3% in average. Statistical dependence was high, which was demonstrated for relationship between Cd in soil, pH and compost. Available Cd forms in soil were 53.3% and soil with compost were 45% in average. The garden compost as a remediation medium reduced Cd bioavailability.

Open access