Склад, екологічна структура та декоративність живоплотів в урбанізованому середовищі Чернівців

Наведено результати досліджень видового складу, просторової, екологічної та вікової структури живоплотів урбанізованого середовища Чернівців. Здійснено комплексне оцінювання якісного стану та декоративності живоплотів у міських зелених зонах та запропоновано заходи з покращення їх декоративності, якісного стану і функціональності. Встановлено, що для дендрофлори живоплотів Чернівців характерне незначне видове різноманіття, зокрема 17 видів деревних рослин із 13 родів та 12 родин. В озелененні міста на територіях загального користування, а також на територіях державних установ і підприємств переважно формують живі огорожі із самшиту вічнозеленого (Buxus sempervirens L.), пухироплідника калинолистого (Physocarpus opulifolius (L.) Maxim.), свидини білої (Cornus alba (L.) Opiz.,), спіреї середньої (Sріraea media Schmidt.) та спіреї Вангутта (Spiraea vanhouttei Zab.). Переважна більшість живоплотів міста розміщена на територіях загального користування (48,8 %) та сформована із одного деревного виду – 98,3 %. За екологічною структурою найчисельнішою в живоплотах відносно трофності ґрунтового субстрату є група мезотрофних деревних рослин – 70,5 %, а відносно вологості ґрунтового субстрату – група мезофітних деревних рослин – 70,6 %. За просторовою структурою серед живих огорож міста найпоширенішими є однорядні – 83,5 % та середні за висотою живоплоти – 63,6 %. Частка бордюрних живоплотів, створених переважно із спіреї середньої, самшиту вічнозеленого та барбарису Тунберга (Berberis thunbergii DC.), є незначною та становить тільки 10,7 %. За віковою структурою в насадженнях міста найпоширенішими є 21-30-річні живоплоти – 57,9 %, а живих огорож віком понад 50 років не виявлено зовсім. Найвища оцінка декоративності у зелених зонах міста характерна для живоплотів, сформованих з барбарису Тунберга, бирючини звичайної (Ligustrum vulgare L.), садового жасмину звичайного (Philadelphus coronarius L.), сніжноягідника білого (Symphoricarpos albus (L.) Blake), спіреї середньої, спіреї Вангутта, свидини білої, свидини криваво-червоної (Cornus sanguinea (L.) Opiz.) та самшиту вічнозеленого. За якісним станом більшість живоплотів у зелених зонах Чернівців належать до категорії "добрих" – 43,0 %, однак частка живих огорож "незадовільного" якісного стану є досить значною та становить 22,3 %. Належне фінансування проведення необхідних агротехнічних заходів та ефективна садово-парково-господарська діяльність сприятимуть покращенню якісного стану, декоративності та естетичної привабливості живоплотів, підвищення їх стійкості до несприятливого антропогенного впливу в урбанізованому середовищі.

Morpho-anatomical and biochemical changes associated with rooting of micropropagated ninebark cuttings

Ninebark (Physocarpus opulifolius) is an attractive ornamental shrub with poor rooting characteristics in some cultivars, which is a limiting factor in commercial production This study was designed to optimize rooting conditions of ninebark cuttings and to observe the effect of exogenous auxin IBA on some morpho-anatomical and biochemical changes associated with rhizogenesis in the in vitro conditions. Both auxins under study: the indole-3-butyric acid (IBA) and 1-naphthalene acetic acid (NAA) gave comparable effects but the combination of ½ MS + 1 mg·L−1 IBA was the most cost effective for all rooting parameters. Anatomical changes at the cuttings’ bases during root formation were typical for woody plants and they were accelerated by auxin in the culture medium. High levels of the endogenous indole acid and hydrogen peroxide were temporarily associated with intensive cell divisions in cuttings, and the polyphenolic acid contents kept increasing during rooting above the initial levels and those in controls.

Biological diversity of insects on woody plants of the Rosacea family in the northern forest-steppe of the Ob region

The aim of the study was to determine the influence of plant species and year conditions on the biological diversity and number of insects – inhabitants of the crown layer of woody plants of the Rosaceae family in the conditions of the northern forest-steppe of the Ob region. The research was carried out in 2017–2018. During the flowering period of woody entomophilous plants, insects were collected by mowing with an entomological net in the crowns and undercrown space (25 strokes in four repetitions). In the crown of woody introduced plants Pyrus ussuriensis (Ussuri pear), Prunus maackii (Maak plum), Amelanchier alnifolia (alder irga), Spiraea betulifolia (spiraea birch leaf), Physocarpus opulifolius growing on the territory of arboretum of RAS in the northern forest-steppe of the Ob region, a total of 2597 insect specimens from 7 orders and more than 30 families were found. The largest number of insects belonged to the order Diptera (49.4 %). Representatives of the orders Thysanoptera (23.7%) and Hymenoptera (11.4%) made a significant contribution to the formation of the entomofauna. The entomofauna of different species of woody plants from the Rosaceae family differed in the taxonomic groups of insects and their numbers. A high degree of enomofauna similarity (Jaccard coefficient is 0.75) was found between Amelanchier alnifolia and Pyrus ussuriensis with similar flowering periods. A low degree of similarity was found between Amelanchier alnifolia and Spiraea betulifolia (0.32) and between Pyrus ussuriensis and Physocarpus opulifolius (0.33). The species of the plant (38.1 and 26.1%, respectively) had the greatest influence on the biological diversity and the number of entomocomplexes, which indicates the adaptation of insects to a woody plant of the Rosaceae family. The conditions of the year significantly (by 9.8%) influenced the biological diversity of insects during the flowering period.

Acclimation to Ex Vitro Conditions in Ninebark

Acclimation is the final phase of micropropagation and often decisive for its economic output. The aim of the experiments was to evaluate the effect of abscisic acid (ABA) and supplementary light on acclimation and leaf anatomy of the in vitro-rooted plants of ninebark (Physocarpus opulifolius L.). The initial material came from 8–10-week-old in vitro cultures on ½MS supplemented with 1 mg·L−1 IBA. After potting, plantlets were sprayed with ABA solutions or distilled water and were grown either under natural daylight or under supplemental sodium light at 230 μmol·m−2·s−1 between 2 and 9 p.m. All measurements and anatomical observations were done after eight weeks in the greenhouse. Supplementary lighting significantly increased the percentage of acclimatized plants, plant height and the internode number. Plant growth was also positively affected by 1 mg·L−1 ABA. During acclimation, the photosynthesis rate increased while the transpiration and stomatal conductance dropped. The assimilation pigment contents increased under supplemental lighting while ABA had no detectable effect. However, relative to water controls, ABA increased photosynthesis, reduced transpiration, and stomatal conductance in plants growing under both light conditions. Leaves from the in vitro plants were about two times thinner than those from plants growing in soil, with only a single layer of the palisade parenchyma, hence with lower proportion in relation to the spongy parenchyma. Supplementary light during acclimation increased leaf thickness but only in the water control while it decreased it in the ABA-treated plants. ABA increased the mesophyll thickness but only in plants growing under natural light. In conclusion, supplementary light and treatment with ABA enhance acclimation of micropropagated ninebark plants.

Optimizing micropropagation conditions for a recalcitrant ninebark (Physocarpus opulifolius L. maxim.) cultivar

Ninebark is a very popular ornamental shrub. Micropropagation is an efficient method for mass production of uniform plant material. This study was designed to develop and optimize conditions at all phases of ninebark micropropagation. For the multiplication stage, the Murashige and Skoog (MS) medium at full concentration and pH 5.8 was chosen as the basal medium. Sorbitol proved a more effective carbohydrate source than fructose, with no adverse effects on shoot vitrification or the medium itself. The best shoot production, both in number and length, was on the medium enriched with 2 and 3 mg·L−1 zeatin. High numbers of shoots were also obtained in treatments with 1 mg·L−1 6-benzyladenine (BA) or 2 mg·L−1 meta-Topolin (mT) in the basal medium. BA was the most cost-effective cytokinin. There was a positive effect of the gibberellic acid on proliferation: the highest shoot number per explant was produced in the presence of 1 mg·L−1 GA3. No effect of the culture age (up to 20 subcultures) on the percentage of regenerating explants was evident, and the highest numbers of shoots were obtained between passages 10 and 17. For rooting, the MS medium at half strength was used. The best rooting was at 1 mg·L−1 IBA. Spraying the in vitro rooted cuttings with abscisic acid (ABA) favored plant acclimation to the ex vitro conditions. Exvitro rooting, including the treatments with IBA and ABA, shortened the production time by approximately one third.

Elements of topiary art of reserved man-made parks of the second half of the XX century

Elements of topiary art were studied in eleven park-monuments of landscape art (PMLA) and five complex monuments of nature (CMN), created in the second half of the twentieth century. To the elements of topiary art belong: shaped plants, plant-borders, hedges, living walls, pylons, berso, bosquets, and parterres. In PMsLA “Bondaretsky” and “Vysokivsky” were found no elements of topiary art. In nine PMsLA and five CMsN of Ukrainian Polissya were present five elements of topiary art (plant-borders, hedges (low, medium, high), living walls, pylons and shaped plants (ball, pyramid, cone, cube, complex geometric figures). The most common are plant-borders formed from Buxus sempervirens L., trimmed hedges from Picea abies Karst. and Thuja occidentalis L., untrimmed hedges from Juniperus sabina L., Physocarpus opulifolius Maxim., and Sorbaria sorbifolia (L.) A.Br., pylons and shaped plants in the form of a sphere, cube, complex geometric shapes - from Thuja occidentalis L. 12 families, 24 genera, 24 species, and 3 cultivars represent the systematic structure of woody plants in the elements of topiary art. Deciduous species of woody plants, namely the family Rosaceae Juss, prevail. In the elements of topiary art of PMLA and CMN there are species that are protected by the IUCN Red List (58 %), belonging to two categories of rarity NT (4 %), LC (54 %). In terms of the height of woody plants in the elements of topiary art, trees and shrubs are represented in equal numbers. By height, among tree plants prevail trees of the first magnitude 26 % and medium bushes 29 %, whereas there are slightly fewer trees of the fourth magnitude (15%) and high bushes (22 %). The condition of woody plants of 24 species and three cultivars is good, except for woody plants where timely and proper care was not carried out (formation of longitudinal and transverse profiles and annual pruning). Some plants should be replaced because of loss of aesthetics due to age.

THE COMPOSITION AND CONTENT OF PHENOLIC COMPOUNDS IN THE LEAVES OF A POTENTIALLY INVA-SIVE SPECIES PHYSOCARPUS OPULIFOLIUS (L.) MAXIM. AND ITS ORNAMENTAL CULTIVARS

The expansion of alien plant species in natural communities is now taking a global scale. Since most invasive plants have economically valuable properties, many researchers agree that these plants must be used as new sources of biological resources. The composition and content of biologically active compounds were studied in the leaves of potentially invasive species of Novosibirsk – Physocarpus opulifolius (L.) Maxim. and its ornamental cultivars Ph. opulifolius ‘Diabolo’, Ph. opulifolius ‘Luteus’ by the method of High-Performance Liquid Chromatography. For the first time an analysis of phenolic profiles of introduced, self-sown and cultivated Ph. opulifolius plants has been performed. Presence of 22 phenolic compounds represented by several groups of substances with predominating flavanols (hyperoside, rutin, astragalin and quercetin) has been established. Avicularin has been only revealed in the leaves of cultivars. The sum of identified flavonols greatly varies in different samples, the highest content is in the cultivar Ph. opulifolius ‘Diabolo’ (14.68 mg/g) and self-sown plants of Ph. opulifolius (14.22 mg/g). The content of the sum of identified flavons (vitexin, isovitexin, baicalin) and phenolic acid (сhlorogenic and caffeic acids) is almost the same in all Ph. opulifolius samples under study. The data obtained will allow to widen the idea of the resource potential of the aggressive invasive species and its ornamental cultivars in the secondary areal.

Assessment of Plantations Ornamentality

The issue of biodiversity and sustainability of tree and shrub plantations in large cities is relevant both in Russia and abroad. Their ornamentality is an indicator of adaptation and ability to fully perform their functions. It is relevant to create plantations, decorative throughout the calendar year. The research purpose is to develop a scale for assessing the ornamentality of plantations in urban conditions. This procedure is based on scoring the following characteristics of green spaces: sanitary state; decorative qualities of trunk and crown; characteristics of flowering (according to duration, abundance, color and size of flowers); characteristics of leafing (variety of summer and autumn colors, total duration of leafing). There are 5 most common types of plantations: single-breed arboreal; single-breed shrub; mixed wood; mixed shrub; and woodshrub groups, in which the research was carried out. A mixed group of blue spruce (Picea pungens Eng.), bird cherry (Padus racemosa Lam.) and Hungarian lilac (Syringe josikae Jacg.) has the highest degree of ornamentality in northern conditions (24.8 points). A single-breed plantation of common ninebark (Physocarpus opulifolius L.) has the least ornamentality score (13.1 points), which is due to its sanitary state. The total score depends not only on the species assortment, but also on the plantation sanitary state. The ornamentality score increases with distance from the road, which is due to the improvement in the sanitary state of trees and shrubs (22.8 points at a distance versus 21.4 points near the road). Among all the studied types of plantations in the cities of the Arkhangelsk agglomeration, 50 % have a high degree of ornamentality, 45 % – medium and 5 % – low. Single-breed plantations are generally less decorative than mixed (20.5 points versus 23.4 points). Urban plantations are more or less decorative throughout the entire calendar year. The proposed scheme of the procedure assumes an assessment of decorative effect during all seasons of the year. So, the following should be recorded: the beginning of the period of leafing and flowering in spring; the sanitary state, flowering (duration, abundance, color and size of flowers) in summer; the color scheme of the leaves, the total duration of leafing in autumn; the decorative qualities of trunk and crown (architectonics of crown, coloring of branches) in winter.