Abstract: Spiraea are beautifully flowering shrubs that are valued for their high decorative value, a variety of bush shapes and flower colors, abundant flowering, unpretentiousness and high resistance. The exact dates of flowering may vary depending on the climatic conditions of region, so the study of flowering periods in a particular region of introduction is relevant. The purpose of the study was to determine the flowering dates of the species Spiraea in the Botanical Garden-Institute of the Volga State University of Technology (Yoshkar-Ola, Mari El Republic). The observations were carried out in 2023. The objects of the study were 56 species and varieties in the exhibition "Fruticetum". The duration of flowering was 3 months – from May 6 to August 5. In the period up to mid–June, mainly plants with white flowers bloomed, and only 2 species with pink ones – S. Billardii and S. Densiflora. Since the second half of June, the flowering of pink-colored Spireas has prevailed. The distribution of the studied Spiraea into groups with early, medium and late onset and end of flowering has been carried out. A flowering calendar has been compiled. The species S. corymbosa had the longest flowering (56 days), also long-bloomed S. Rubella, S. Latifolia, S. Bumalda and its cultivar 'Antony Waterer', S. Salicifolia and its cultivar 'Alba', S. Humilis, S. Lemoinei, S. Syringaeflora, S. Rosthornii. The data obtained are of value to specialists in the field of landscaping. A limited number of Spiraea species are used in the plantations of settlements of the Mari El Republic, and thanks to the extensive collection of Botanical Garden-Institute, it is possible to enrich the range of Spiraea in urban plantings.

Abstract: Clematis is one of the highly ornamental plants used in landscaping, but they are often susceptible to diseases as a result of abiotic and biotic factors action. The article presents an overview of diseases and pests of clematis. Among them, wilt is especially dangerous, which leads to a sharp withering of plants. Also, clematis can be affected by rust, powdery mildew, gray rot, various types of spotting, etc., as well as pests nematode, worm, aphids, spider mite, slugs, etc. Information on pest control and diseases of clematis is presented. Possible signs of weakening of non-infectious plants are indicated. The diseases identified during the visual examination of clematis in the Botanical Garden-Institute of VSUT (Yoshkar-Ola) are given. The plants grow on the lianas site of the Fruticetum exposition. Wilting was observed in plants older than 20 years: symptoms were detected in 1/3 of plants. Most of the collection plants showed signs of spotting. In some varietal clematis, small-leaved was observed. Damage by leaf-eating insects and mice, as well as mechanical damage from hail and rain were revealed. Agrotechnical measures carried out for the prevention of diseases are presented. The obtained data can be used in the practice of growing clematis at the landscaping facilities of settlements in the region.

Abstract: Dahlia Cav. is a beautifully flowering perennial plant from the family Asteraceae Dum. It has storing root tubers that do not survive during the winter in the open ground of central Russia. This crop is characterized by a high variety of colors, shapes and sizes of inflorescences, different plant heights, long-term stable decorative effect from the beginning to the end of the growing season. The purpose of the study is to analyze the Dahlia × cultorum collection in the Botanical Garden-Institute of the Volga State University of Technology (Yoshkar-Ola, Mari El Republic). As of 2021, plants of 32 cultivars were grown in the exposition «Ornamental Herbaceous Plants», each cultivar is represented by 1-5 plants. It is established that the available cultivars belong to 6 classes according to the structure of inflorescences, the largest number of them belong to the class of Decorative and Semi-Cactus (12 and 8 names, respectively). According to the color of the inflorescences, the largest number of cultivars has bicolor inflorescences. The small-flowered cultivars dominated according to the inflorescences size. In general, most cultivars with large and medium-sized inflorescences have a decrease in their size. We can replenish the collection with varieties from the smallest represented classes, as well as the missing 6 classes. The results can be used in the practice of settlements landscaping of the Mari El Republic and nearby regions.

Abstract: Daffodils are decorative spring-flowering bulbous plants characterized by unpretentiousness to growing conditions, abundant flowering and variety of flower shapes. The timing of their flowering depends on varietal characteristics, weather conditions and climatic conditions of the growing point. The purpose of this article was to study the seasonal development of 6 Daffodils varieties in the Mari El Republic. Observations were carried out in the Botanical Garden-Institute of the Volga State University of Technology (Yoshkar-Ola). The objects of the study were varieties: small-cupped– 'Carnmoon' and 'White Lady', large-cupped – 'Duke of Windsor' and 'Odense', double – 'Texas' and 'Yellow Cheerfulness'. Observations were carried out in 2014-2019 according to the methodology of the Main Botanical Garden of the Russian Academy of Sciences. It was found that the varieties starting vegetation later had a longer vegetation period. The dates of the beginning and mass flowering correlated with the dates of complete leaf death. The variety 'Yellow Cheerfulness' had the late passage of all studied phenophases, as well as the shortest duration of vegetation and growth. The variety 'Odense' was characterized by the early end of leaf growth, budding and flowering. The variety 'White Lady' had a long vegetation period and the leaf growth period, a late flowering end and a long flowering duration. The short duration of flowering is established in the variety 'Carnmoon'. The data obtained are of interest in the practice of daffodils growing in the settlements of the Mari El Republic.

Abstract: Organic acids and carotenoids are important biologically active compounds that largely determine the pharmacological value of rowan fruits. In medicine, mountain ashberry is used as a multivitamin, diuretic, tonic. Its fruits are standardized according to the content of organic acids. In this work, the content of the organic acids sum and carotenoids in the fruits of Sorbus aucuparia and the varieties 'Burka', 'Granatnaya', 'Alaya Krupnaya' and 'Titan' from the collection of the Botanical Garden-Institute of Volga State University of Technology (Yoshkar-Ola, Mary El Republic) was studied. The moisture content in the fruits of all studied rowans varied from 0.49 to 0.60%, which corresponded to the permissible value of the pharmacopoeia. The amount of organic acids varied from 3.06 to 3.93%. In the fruits of the varieties 'Titan' and 'Burka' the greatest amount of the organic acids was found, slightly less was in the variety 'Granatnaya', but the difference is insignificant. The low content of the studied compounds was determined in Sorbus aucuparia and 'Alaya Krupnaya', while the value of this variety did not meet the requirements of the pharmacopoeia article. The content of carotenoids in rowan fruits varied from 3.09 to 5.60 mg%. In terms of the number of these compounds, the fruits of the varieties 'Titan' and 'Alaya Krupnaya' were in the lead. The smallest amount of carotenoids was found in the fruits of Sorbus aucuparia and 'Granatnaya'. The most promising for obtaining biologically active compounds is the variety 'Titan'.

Abstract: Gladiolus L. are beautifully flowering perennials that do not overwinter in the open ground in the conditions of central Russia. Its varieties are characterized by a huge variety in the height of the peduncle, the color scheme and the corrugation degree of the flowers. The disadvantage of this crop is the complexity of the annual digging and planting of corms. The purpose of the article is to study the growth dynamics of real gladiolus leaves in the open ground. Leaf height measurements were carried out after 15 days in the process of growing plants on ridges. The objects of the study were 9 varieties: 'Aurora', 'Granatovyj braslet', 'Grad Kitezh', 'Devichi tajny', 'Dolgozhdannyj debyut', 'Majya Plisetskaya', 'Tanyusha', 'Shapka Monomaha', 'Noon Moon'. The study showed that the most intensive growth of gladiolus leaves occurred after the emergence of sprouts. On the 20th day after planting, the plants reached about 1/3 of their final height, and on the 35th day – 50%, after 2 months – the height was almost 90%. Most varieties were characterized by the greatest increase in the first accounting period, in the future its value decreased, reaching a minimum in the last accounting period. In the process of growth, the taller varieties remained tall, the shorter ones remained stunted. At each date of the study, 'Devichi tajny' had the highest height, 'Grad Kitezh' had the lowest height. The obtained data can be used in the cultivation of gladioli in nurseries and landscaping location.

Abstract: Viburnums are of economic importance, are an important component of forests, they are used in landscaping, have medicinal and nutritional value. The purpose of the study is a comparative analysis of characteristics of seeds of 4 viburnum species in the conditions of the Mari El Republic. The authors study the pyrenes collected in 2018-2020 from the plants grown in the exposition "Fruticetum" of the Botanical Garden-Institute of VSUT (Yoshkar-Ola). The mass of 1000 seeds was determined according to GOST 13056.4-67, the sizes of 30 seeds were measured with a caliper. It was found that the studied viburnums form seeds of typical size and weight. Viburnum lentago had the largest seeds, Viburnum lantana had the smallest ones. A significant influence of the species specificity factor on the weight of seeds was revealed, while no significant influence of the factor of weather conditions of different years on the seed indicators was established. The weight of the seeds was very closely positively correlated with their length and significantly with their thickness. The thickness of the seeds was characterized by the highest level of variability, negatively correlated with their width and positively with their length. During the 3 years of the study, the heaviest seeds in most species were formed in 2018.

Abstract: There is the site of lianas as a part of the exposition «Fruticetum» in the Botanical Garden-Institute of Volga State University of Technology. It is an area of 0.15 hectares, with 5 rows of metal supports 1.5–3.0 high. Woody plants of 98 names from 14 genera of 10 families grow here: Actinidiaceae, Aristolochiaceae, Bignoniaceae, Caprifoliaceae, Celastraceae, Hydrangeaceae, Menispermaceae, Ranunculaceae, Schisandraceae, Vitaceae. The largest number of taxa in the collection includes the following genera: Clematis – 54 taxa, Vitis – 10, Lonicera – 7. The most widely represented family is Ranunculaceae (56 taxa). The Vitaceae family contains the largest number of genera (3). Cultivars and hybrids have the main share in the collection (62.2%). The cultivars of clematis are the most numerous (42 names). They have a high decorative value and are an undoubted decoration of the site. The low ornamental shrubs and perennial herbaceous plants are planted in the exposition to increase the decorative effect. The article provides information about winter hardiness, growth and development of lianas, as well as the features of agrotechnical measures. The directions of development are presented. These data are of interest to employees of botanical gardens, students of plant-growing directions and amateur gardeners. The materials are accompanied by photographs.

Abstract: Hazelnuts have an important nutritional value. Breeders have bred a number of varieties capable of forming high yields in the conditions of the Central part of Russia. The purpose of this study was to analyze the fruit indicators and the reproduction potential of hazelnut variety 'Academic Yablokov' in the Mari El Republic. The advantage of this variety is large fruits and purple leaf color. The studies were conducted in 2020 and 2021 in the Botanical Garden-Institute of Volga State University of Technology (Yoshkar-Ola). The study showed that nuts have the mass of 2.0-2.4 g, the length and diameter of 2.4-2.6 and 1.4–1.6 cm, respectively. In the abnormally hot and dry conditions of 2021, the variety fruits were lighter and smaller compared to the excessively humid conditions of 2020. But the seed quality remained relatively high in both years of the study (82-84%). Sowing nuts using peat and sand as substrates revealed different soil germination of seeds in the experimental variants. The smallest number of seedlings was obtained in the peat variant (26%). The highest germination rate was established in the control variant (43%), but in the future the seedlings turned out to be in less favorable conditions for growth – by autumn they had the smallest height, diameter of the root neck, and number of lateral shoots. The seedlings in the variant with sand had the greatest height and length of the root system.

Abstract: As part of the Botanical Garden-Institute of the Volga State University of Technology, a collection of ornamental shrubs is presented in the exposition "Fruticetum". As of 2020, plants from 86 genera of 30 families grow here. The largest number of taxa in the collection includes the following genera: Syringa – 97, Spiraea – 61, Philadelphia – 48, Berberis – 30, Lonicera – 24, Rosa – 22. The largest families are Rosaceae (167 taxa), Oleaceae (97), Hydrangeaceae (77), Caprifoliaceae (35), Berberidaceae (31). The most genera contain the families Rosaceae (28 names), Fabaceae (10), Oleaceae (5), Caprifoliaceae (5), Cupressaceae (4). Angiosperms include 505 taxa, gymnosperms – 26 taxa. The main share in the composition of the collection of Fruticetum are varieties and hybrids – 305 names, there are 226 species of plants, which is associated with the main purpose of the exposition – to present a variety of assortment of ornamental shrubs. Mandatory scientific research includes an annual assessment of winter hardiness, a note on the presence of flowering and fruiting in all plants in the exposition, conducting phenological observations of a number of plants. The features of agrotechnical measures carried out in the exposition (pruning, fertilizing, watering, weeding, pest and disease control, shelter for the winter, mowing grass) are indicated.

Abstract: Crocuses are beautifully flowering corm-bearing plants. They begin the growing season immediately after the snow melts. The research contains the results of phenological observations of 2014-2019 for plants of 6 Crocus taxa in the conditions of the Mari El Republic. Cultivars with early, medium and late periods of phenophase passage were identified. A flowering phenospectrum of the studied crocuses has been compiled. Crocuses vegetate from mid-April to early June for 40-50 days, and bloom from the third decade of April to early May. C. chrysanthus 'Prince Cloues' is characterized by the earliest unfolding of leaves and a short duration of their growth. The greatest value for landscaping is C. versicolor, characterized by the longest growing season and the earliest flowering, as well as C. chrysanthus ' Romance’ and C. angustifolia, characterized by the longest flowering within 2 weeks. The flowering of C. sieberi 'Spring Beauty’ is unstable. The obtained data on the seasonal development of crocuses can be used when including them in rockeries, alpine slides and other flower beds in natural-style gardens.

Abstract: Representatives of the genus Pentaphylloides are low ornamental shrubs that are valued for long abundant flowering, compact size and unpretentiousness to growing conditions. P. fruticosa is a valuable plant that has not only decorative value, but also food, medicinal, soil protection. For medicinal purposes, young flowering shoots are used, harvested during budding and flowering. The article presents the results of phenological observations in 2018-2020. The objects of the study were plants of 8 kinds of Pentaphylloides in the collection of the Botanical Garden-Institute of Volga State University of Technology (Yoshkar-Ola, Mari El Republic). The studied plants undergo most phases of seasonal development, with the exception of the mass end of shoot growth, complete lignification of shoots, mass ripening of fruits, mass leaf fall. Species and cultivars vegetated from the end of April – the beginning of May to the end of October in a short time. The vegetation period was 177-182 days. There was no significant difference in the timing of the passage of phenophases between the taxa. Plants of Р. × friedrichsenii and P. mandschurica passed most of the phenophases earlier than the average dates for the genus, and 'Goldfinger' and 'Klondike' – later. The earliest and longest flowering was characterized by P. friedrichsenii (65 d.), the latest and shortest – P. fruticosa (28 d.). All plants of P. fruticosa cultivars bloomed for a longer period than the species. After mass flowering, single flowers were observed in representatives of Pentaphyloides until mid-October.

Abstract: Species of the genus Philadelphus L. (mock orange) are among the most popular ornamental shrubs. They are valued for low maintenance, abundant flowering, exceptional aroma of flowers and a prolonged flowering period during high summer, by when many shrubs already fade. The results of phenological observations of 2018-2020 are presented in the article. The objects of the research were the plants of 8 cultivars of mock orange selected by N. K. Vekhov in the Botanical Garden-Institute of VSUT (Yoshkar-Ola, Mari El Republic). The vegetation of plants lasts from the beginning of May to the end of September and has a duration of 177-189 days.  The 'Airborne force' (Vozdushny desant) cultivar was characterized by the longest growing season.  The full leafing occurred in the first decade of June, the growth of scions ended in the first half of August. Flowering began in the third decade of June and lasted on average for 13-28 days. The cultivar 'Vosdushny Desant' has the earliest beginning of flowering, 'Arktika' has the latest one. The plants of 'Elbrus' were characterized by the longest flowering, 'Yunnat' – by the shortest one. There was no connection between the duration of flowering and the structure of flowers.

Abstract: Deutzia is an ornamental flowering shrub valued for its abundant long-term flowering and the elegance of flowers shape. The research objects are the plants of 3 species and 1 variety of Deutzia in the Botanic Garden-Institute of VSUT (Yoshkar-Ola, Mari El Republic). Plants aged from 38 to 45 years grow in the exhibition “Fruticetum”. The study was conducted in 2015-2019. The height and diameter of plants crowns, their winter hardiness for the period from 1981 to 2019, the morphometric indicators of leaves and inflorescences, the possibility of vegetative propagation by herbaceous cuttings, and the size of annual plants were studied. According to the study results, the most hardy is Deutzia of Amur, which forms the highest shrubs. The long-leaved Deutzia has the longest leaf blades, Deutzia scabra ‘Plena’ has the smallest leaves. The long-leaved Deutzia has the largest inflorescences, Deutzia of Amur and Deutzia scabra ‘Plena’ have the smallest ones. Deutzia magnifica and Deutzia scabra ‘Plena’ have ornamentality advantage over other species due to the double flowers. For the maximum display of ornamental qualities, the plants need a successful overwintering. The greatest ability to reproduce by herbaceous cuttings is noted for Deutzia scabra ‘Plena’. The results of this study are important for the Deutzia application in the garden and park construction. In the landscaping of the republic settlements Deutzia is recommended for the target assortment.

Abstract: The article contains the results of the 2014 - 2018 phenology observation over 6 maple tree species (Acer L.) with natural habitats in North America. The objects of research were plants of the Botanical garden-Institute of VSUT: A. negundo, A. pensylvanicum, A. rubrum, A. saccharinum, A. saccharum, A. spicatum. The studied maples began growing at the end of April – the first decade of May and ended in October. The first, in the first decade of May, bloomed A. saccharinum and A. rubrum. Later blooming species were characterized by a longer flowering period, the latest and longest flowering within 20 days was observed in A. spicatum. Despite the different periods of flowering, the fruits of different species ripened relatively amicably, in the second half of September. The longest vegetation period was found in A. saccharinum (169±2.1 days), and this species is characterized by late autumn leaf blooming. The greatest period of autumn leaf blooming, more than a month, was characterized by A. spicatum. The studied species can be used in landscaping of the Mari El Republic settlements as part of an additional assortment, with the exception of A. negundo, which is a weed plant. Despite the similar timing of the passage of many phenophases, the variety of maples morphological features (shape and size of leaves, flowers and fruits, bark color, etc.) allows them to be used for decorative purposes. During the study period, the earliest passage of most phenophases was recorded in 2016, and the latest in 2017 and 2018.

Abstract: Daylily (Hemerocallis) is a perennial herbaceous plant widely used in landscape gardening. Daylilies are prized for their long term flowering mainly in late summer and low maintenance cultivation. According to flower spike height, the varieties are divided into runt, medium-growing and tall. The article contains the results of the study of 21 medium-growing daylily varieties’ terms of flowering in the botanic garden of the Volga region State University of Technology (Yoshkar-Ola, the Republic of Mari El). The research was conducted in 2015 - 2017. The calendar dates were converted into a continuous series. All varieties were classified as early, medium or late according to the terms of the beginning and the end of flowering and its duration. During three years of research, the earliest beginning of the phenological phase was registered in 2016, and the latest one  - in 2017. The early beginning and ending of flowering were typical for the varieties “Dr Regel” and “Royal Sovereign”. The late beginning of flowering was registered for the “Country Club” variety, and the late ending - for “Sandalwood”. Other varieties were classified as medium-term. The varieties “Royal Sovereign”, “Tejas”, and “Sugar Candy” are characterized by a short flowering period, while “Sandalwood” and “Derby Bound” - with a long one. It was established that the late-flowering varieties are characterized with a longer flowering period.

Abstract: The article contains the results of observations over 5 maple (Acer L.) species conducted in 2014 - 2018. The research objects are the plants growing in the Botanic garden of the Volga region State University of Technology: A. campestre, A. platanoides, A. pseudoplatanus, A. tataricum, A. trautvetteri. Their natural habitats are in the Caucasian-European region. In the wild, only A. platanoides grow on the territory of the Republic, others are introduced species. The authors analyze weather conditions over 5 years of research and establish that at higher average daily temperatures in 2016, the seasonal development stages came earlier, while colder weather conditions of 2017 hampered the phenophase. On average, the maples under study started vegetation in the first decade of May, and finished it in the third decade of September - mid October. The earlier vegetation started, the earlier sprouts started growing and flowering began. The easiest flowering was registered for A. platanoides in the second decade of May, then for A. campestre in the third decade of May. The latest and the longest flowering was registered for A. tataricum. Long-vegetating species were characterized by long growing of sprouts and late fall of leaves. In the autumn period, A. campestre and A. tataricum are the fanciest with a long period of leaves coloring.  A. pseudoplatanus and A. trautvetteri don’t have a phase of generative development due to poor winter resistance, and are not recommended for use in landscaping. 
 

Abstract: Among fruit crops, Rowan is one of the most winter-hardy. In Russia, the predominant varieties are those derived from Sorbus aucuparia. Rowan fruits are used in fresh and dried form, they are valuable in food, dietary, and medicinal terms. The objects of this study were 7 Rowan varieties in the exposition «Wild fruit plants» of the Botanical garden-Institute of Volga State University of Technology (Yoshkar-Ola, Mari El Republic). The research was conducted in 2014–2019. The fruits were collected in the mass maturation phase and weighed in 3 samples of 100 pieces. The yield of air-dry fruits, expressed as a percentage, was obtained by the ratio of the mass of dried fruits to the mass of freshly harvested ones. It was found that the varieties ‘Alaya Krupnaya’, ‘Titan’, ‘Granatnaya’, and ‘Burka’ are characterized by large fruits. ‘Desertnaya Michurina’, ‘Nevezhinskaya’, and ‘Doch Kubovoy’ are small-fruited varieties. The most favorable for fruiting of most varieties were 2016 and 2019 with dry conditions of the growing season. Excessively moistened conditions in 2017 negatively affected the formation of Rowan fruits. The yield of air-dry raw materials was inversely correlated with the weight of fruits. The obtained data can be used in the organization of plantation cultivation of Rowan varieties in the conditions of the Volga-Vyatka region.