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Abstract

Mantle vegetation includes plant communities dominated mostly by shrubs and occurs in habitats where the typical tree layers meet difficulties to evolve. This study was conducted in three areas of Bulgaria – Western Balkan Range, Western Sredna Gora Mt. and the Fore-Balkan. Numerical classification and ordination were performed by PC-ORD and JUICE software packages. Diagnostic species were determined by calculating the Phi-coefficient. Two associations and one plant community of the Berberidion alliance were recognized – Corno-Ligustretum Horvat ex Trinajstić ---amp--- Z. Pavletić 1991, Pruno spinosae-Ligustretum vulgaris Tüxen 1952 and Elytrigia repens-Crataegus monogyna community. The latter considered as a successional stage of shrub encroachment into the grasslands. Its species composition is very close to that of the ass. Corno-Ligustretum. The species composition of ass. Pruno-Ligustretum represents a mixture of species characteristic for dry and mesic grasslands, fringe and forest vegetation. The Crataego-Prunetea class is still poorly studied in Bulgaria and much more data from all regions in the country have to be collected.

Abstract

Echinophora spinosa L., a perennial member of the Apiaceae (Umbelliferae) family is known to be native to southern Europe and Algeria. More recently this taxon was collected from Tabarka (Jendouba-Kroumiria, North-Western of Tunisia) and is reported as a new species for the terrestrial flora of Tunisia. It is described and illustrated and notes on its ecology and phytosociological remarks are provided.

Abstract

Based on hierarchical classification of more than 300 phytosociological relevés of basophilic black and (or) Scots pine communities in the Southern, Eastern and Southeastern Alps we described a new association Rhodothamno chamaecisti-Pinetum sylvestris, into which we classify stands that have until now been discussed in the framework of subassociations Fraxino orni-Pinetum nigrae pinetosum sylvestris, laricetosum deciduae and (partly) caricetosum humilis, and are floristically slightly similar also to certain forms of the association Erico-Pinetum sylvestris. The stands of the new association are for now classified into Natura 2000 habitat type Southeastern-European Pinus sylvestris forests (91R0), within it we propose a special habitat subtype Southeastern-Alpine Scots pine forests, and into a new forest site type Southeastern-Alpine Scots pine forest. At the contact of the Julian and Dinaric Alps we described a new subassociation Genisto januensis-Pinetum sylvestris campanuletosum cespitosae, which comprises also a Natura 2000 species Primula carniolica.

Abstract

The study presents a floristic-sociological classification of the forest vegetation of Kyiv urban area. We identified 18 syntaxa within 7 classes, 7 orders, 8 alliances, and 3 new associations were allocated (Aristolochio clematitis-Populetum nigrae, Galio aparines-Aceretum negundi, Dryopterido carthusianae-Pinetum sylvestris). We analyzed vegetation data using quantitative approaches of ordination and phytoindication. Considering many relevés of transitional nature in the collected data on urban forests, the clustering algorithm of DRSA (Distance-Ranked Sorting Algorithm) was applied to classify vegetation matrix. Large-scale comparative floristic analysis of syntaxa from different regions and countries have been conducted and summarized in differentiating tables.

Abstract

The Central Anatolian vegetation has diverse site conditions and small-scale plant diversity. For this reason, identification of plant communities is important for understanding their ecology and nature conservation. This study aims to contribute the syntaxonomical classification of the Central Anatolian vegetation. The study area is situated among Güzelyurt, Narköy, and Bozköy (Niğde) in the east of Aksaray province of Central Anatolia in Turkey. The vegetation data were collected using the phytosociological method of Braun-Blanquet and classified using TWINSPAN. The ecological characteristics of the units were investigated with Detrended Correspondence Analysis. Three new plant associations were described in the study. The steppe association was included in Onobrychido armenae-Thymetalia leucostomi and Astragalo microcephali-Brometea tomentelli. The forest-steppe association was classified under Quercion anatolicae in Quercetea pubescentis. The riparian association is the first poplar-dominated one described in Turkey and, classified under Alno glutinosae-Populetea albae and its alliance Populion albae.

Abstract

Extensive tall-trunk orchards, an important element of the central European landscape since the Middle Ages, conserve potential for the future regarding their biodiversity, land use policy and agricultural value. For these reasons, extensive tall-trunk orchards are interesting with regard to nature conservation. Once the management of these low-productivity vegetation sites ceases, the habitat is threatened by successive overgrowth by shrub vegetation. Taking abandoned tall-trunk cherry orchards with dry/mesophilous grassland undergrowth in the locality of Kaňk as an example, the degree of colonization of orchards by woody species and differences in the structure of vegetation cover in different periods after abandonment were monitored. The results showed that the cover of cherry trees in orchards abandoned before 1990 was approximately 30% lower than in orchards abandoned after 2000. The cover of the herb layer in orchards abandoned before 1990 was approximately 60% lower than in orchards abandoned after 2000. The species diversity of orchards abandoned before 1990 was statistically significantly lower than that of orchards abandoned after 2000. The total cover of all species in habitat in areas of medieval ore extraction was approximately 50% lower than that in land originally used for farming.

Abstract

Thrips tabaci Lindeman is a cosmopolitan and polyphagous insect pest. It is known worldwide and recorded on more than 300 plant species. T. tabaci is a key pest of onion and several other crops, and its control is vital to the production and profitability of crops. If onion thrips population is not controlled, damage can reduce yield volume and quality. In addition to direct damage to the host plants, T. tabaci has been characterized as an asymptomatic vector of three devastating tospovirus species, such as Tomato spotted wilt virus, Iris yellow spot virus, and Tomato yellow ring virus. For this reason, several synthetic insecticides were used for control. However, these insecticides bring unwanted effects, like pesticide resistance, elimination of nontarget species, environmental pollution, and threats to human health. To solve the negative consequences of insecticides, biopesticides, such as plant secondary metabolites, entomopathogenic viruses, bacteria, fungi, and nematodes, have been recognized as effective alternatives. The use of plant-based insecticides and entomopathogenic control methods gained more attention in integrated pest management. Their strong side is lack of residues, saving beneficial insects and minimizing air and water pollution. Plant-derived compounds and entomopathogenic biological control agents offered a variety of biological modes of actions against onion thrips, such as repellency, feeding deterrence, anti-oviposition, fecundity deterrence, metamorphosis inhibition, and parasiting the host’s body.

Abstract

In this study, the full cDNA sequences of HcADH2 and HcADH3 were cloned from Hedychium coronarium. The amino acid sequences encoded by them contained three most conserved motifs of short-chain alcohol dehydrogenase (ADH), namely NAD+ binding domain, TGxxx[AG]xG and active site YxxxK. The highest similarity between two genes and ADH from other plants was 70%. Phylogenetic analysis showed that they belonged to a member of the short-chain dehydrogenases/reductases 110C subfamily, but they were distinctly clustered in different clades. Real-time polymerase chain reaction analyses showed that HcADH2 was specifically expressed in bract, and it was expressed higher in no-scented Hedychium forrestii than other Hedychium species, but was undetectable in Hedychium coccineum. HcADH3 was expressed higher in the lateral petal of the flower than in other vegetative organs, and it was expressed the most in H. coronarium that is the most scented among Hedychium species, and its expression levels peaked at the half opening stage. HcADH2 and HcADH3 had almost no significant expression in leaves, but HcADH2 was expressed in response to external stimuli. The mechanical injury and methyl jasmonate (MeJA) treatment could induce expression of HcADH2 in leaves, whereas HcADH3 could have an induced expression only by MeJA. The recombinant HcADH3 protein, but not HcADH2, expressed in Escherichia coli-catalysed conversion of geraniol into citral. It was speculated that HcADH3 had an induced expression in vegetative organ of H. coronarium and took part in monoterpenoid biosynthesis in H. coronarium flowers, but the role of HcADH2 is relevant only for defensive reactions.

Abstract

The current study investigated the effects of gamma radiation on the death rate, morphological traits and meiotic abnormalities in ground-grown chrysanthemum ‘Donglinruixue’, and inter-simple sequence repeat (ISSR) markers were used to identify the DNA polymorphism among mutants. The results showed that the death rate significantly increased with increase in radiation dose. Semi-lethal (LD50) dose was approximately 35 Gy. Compared with unirradiated control, plant growth was significantly inhibited. After irradiation, a series of morphological variations and cytological aberrations occurred in radiated plants. The peak in variation frequency appeared at 35 Gy. In total, ISSR analysis produced 72 scorable bands, of which 64 (88.89%) were polymorphic. The current study demonstrated that gamma irradiation generates a sufficient number of induced mutations and that ISSR analysis offered a useful molecular marker analysis for the identification of mutants.

Abstract

This article is based on a literature review and attempts to highlight the harmful effects of forest soil erosion on aquatic ecosystems with particular emphasis on ichthyofauna. We focus on the phenomena of excessive soil erosion caused by forest management practices and forest roads, subsequent sediment runoff as well as silting of watercourses and their impact on fish. Among others, the direct influence of the suspended sediments on fish reproduction, egg incubation, respiratory processes, growth and immunity, as well as indirect effects on habitat and migration are discussed. The authors’ intention is to draw attention to this important and underestimated aspect of forest management in Poland. The aim of this publication is to bring about changes in the management of commercial forests that will minimize the erosion of forest soils, formation of high levels of suspended solids in rivers and in turn limit their negative impact on aquatic ecosystems.