No 2 (2023)

This article presents the results of a long-term study of the resistance of common apricot cultivars from the VNIISPK bioresource collection to fungal diseases. The most serious fungal diseases for apricot in the conditions of the Central Black Earth region of Russia are coccomycosis and moniliosis (also known as fruit rot). Within the framework of this study, 19 apricot cultivars were selected and studied from the bioresource collection of the VNIISPK (Orel). The cultivars were divided into two groups according to the year of planting. 8 cultivars of apricots planted in 2016 were assigned to group 1, the remaining 11 cultivars planted in 2018 were included in group 2. The studies were carried out in 2017—2022 in the orchard of the VNIISPK genetic collection in the Orel region. The plants were cultivated according to the technology of apricot cultivation generally accepted for this region. Every year, a standard scheme for the protection of plants from diseases and harmful insects for the Orel region was carried out. According to the results of the studies, it was found that all the studied cultivars had a high degree of resistance to clasterosporia and moniliosis. In most of the studied cultivars in both groups, the degree of resistance to clasterosporiasis did not exceed 1.0 points, with the exception of the Agafonovsky cultivar from group 1. A high degree of resistance to moniliosis was also noted in cultivars from group 2, not exceeding 0.5 points. The obtained results can be of wide practical and scientific interest and can be used both in subsequent breeding studies on the complex resistance of apricot to fungal diseases, and when laying industrial orchards with highly disease-resistant cultivars.

An assessment of the introduction of honeysuckle (Lonicera L.) in the conditions of the Moscow region was carried out. Since 1945, 95 taxa of the genus belonging to 2 subgenera, 5 sections and 23 subsections have been tested in the arboretum of the MBS RAS: deciduous shrubs over 2 m high (32.7%, 27 species, 1 variety and 2 ornamental forms), deciduous shrubs 1—2 m high (31.6%, 29 species and 2 ornamental forms), deciduous shrubs less than 1 m (12.2%, 11 species and 1 decorative form), deciduous vines (12.2%, 10 species and 2 decorative forms), as well as semi-evergreen and evergreen shrubs and vines. Plants which native ranges are located in East (20.5%) and Central (15.1%) Asia, as well as the ones in cultivation only (15.1%) prevailed. By 2021, the collection includes 67 taxa: 62 species, 1 variety and 4 cultivars belonging to 2 subgenera, 3 sections and 12 subsections. Most of them are deciduous shrubs over 2 m high (47.8%, 20 species, 1 variety and 1 cultivar), deciduous shrubs 1—2 m high (32.6%, 14 species and 1 cultivar) and deciduous lianas (10.9%, 5 species). Most taxa have native arias in East Asia (23.1%), Russian Far East (14.1%), Europe (12.8%), Western (11.5%) and Central Asia (10.3%). The main reason for the loss of plants from the collection was frost damage – 54.3%. On the basis of the studies, the plants are divided into 3 groups: 1 – recommended for wide use in landscaping within the region (43 species and 1 variety); 2 – recommended for additional introduction trials (37 species); 3 – not recommended for introduction in Moscow region (4 species).

The results of studies on clonal micropropagation of female plants of cloudberry (Rubus chamaemorus L.) of Northern Russian origin at the stage of rooting of microshoots in vitro using the MS nutrient medium and IBA auxin. R. chamaemorus is an economically valuable forest berry species in terms of food and medicine. Plantation cultivation of cloudberry in the conditions of depleted peat deposits will contribute to the restoration of natural berries and increase its productivity. Use the method of micropropagation is advisable to obtain a large amount of planting material in the industrial cultivation of forest berry plants. It is necessary to improve the technology of growing R. chamaemorus in in vitro culture for Northern Russian origin forms. The objects of study are R. chamaemorus plants of the Arkhangelsk, Vologda, Karelian and Khanty-Mansi forms. The maximum values of the number (5.3—7.4 pcs.) and total length (21.7—26.9 cm) of the roots of female R. chamaemorus plants in in vitro culture are noted on the MS nutrient medium, while similar indicators in the variants with dilution of the mineral composition of the nutrient medium by 2 and 4 times are 1.5—2.6 and 2.3—6.4 times less, respectively. An increase in the concentration of IBA auxin from 0.5 to 1.0 mg/l in the nutrient medium contributed to an increase in the number (by 1.4—1.8 times) and a decrease in the average length (by 1.3—1.7 times) of the roots of female plants R. chamaemorus in in vitro culture, as well as an increase in the total length of the roots of the Karelian form (by 1.3 times).

The article presents two-year data (2021—2022) on assessing the effect of technological methods (post-harvest treatments with calcium-containing preparations Master Green Ca and CaCl₂) aimed for increasing the keeping quality of grapes, based on the study of conditional indicators (mass concentration of sugars and titratable acids), monophenol-monooxygenase (MPhMO) enzyme activity, and natural loss of bunch weight of such table grape varieties as ‘Moldova’, ‘Italiya’, ‘Red Globe’ and ‘Shokoladnyi’ in the dynamics of storage. The studies were carried out in the vineyards of Morskoye branch of FSUE PJSC Massandra and in the Laboratory of Grape Storage of the “Magarach” Institute. It was found that treatments with Master Green Ca and CaCl₂ helped to reduce the mass concentration of sugars during the storage relative to the control: by an average of 3—15 % when treated with Master Green Ca, and by 2—8 % when treated with calcium chloride. The use of calcium-containing preparations in general did not have an inhibitory effect on the activity of MPhMO enzyme. At the same time, the minimal activity of MPhMO enzyme (5.1—7.4 c.u./sec*100) in the experimental variant with calcium chloride was registered for all the studied varieties. This enables to reduce significantly the losses caused by the natural loss of bunch weight, relative to the control, by 22—26 %, and by 18—26 %. Post-harvest treatments with calcium-containing preparations made it possible to reduce losses caused by the natural loss of bunch weight in all experimental variants. Dispersion data analysis showed that the natural loss of grape bunch weight during the long-term storage depends by 81.4—98.2 % on the storage period, and by 10.9—17.6 % on the preparation used. The effect of preparations on the natural loss of bunch weight in ‘Shokoladnyi’ and ‘Red Globe’ was not significant. The use of calcium chloride in the form of aerosol treatment improves keeping capacity of grapes during storage; in this case, the optimal concentration of working solution has to be specified. The results obtained make it possible to rationalize the system of the long-term storage of grapes through the use of aerosol treatments with the studied preparations.

The purpose of the study is to examine the characteristics of the seed germination of some taxa from the Castanea genus grown in the conditions of the Moscow region. The objects of study were the fruits of two species of chestnuts: C. dentata and C. sativa, and their interspecific hybrid. Morphological characteristics of fruits were described visually. To measure the fruits, a 250-0.05 mm caliper was used. The fruits prepared for sowing were cleaned from the cupules and stored in the refrigerator (+5ºС), without preliminary drying. Sowing was carried out in containers at a depth of 1—2 cm, in a mixture of neutralized peat, loam soil, sand in a ratio of 3 : 2 : 1. Crops were subjected to cold stratification: containers were kept in an unheated greenhouse for 3 winter months, while they were subjected to natural temperature fluctuations, including short-term freezing of the substrate. It was established that the smallest fruits are C. “dentata” (cf. C. dentata × C. sativa) (Botanical Garden Dresden, Germany): length – 1.689±0.055 cm, diameter – 1.537±0.047 cm. Fruits of C. dentata (MBG RAS Natural Flora Exposition) have the greatest length – 2.290 ± 0.052 cm, and the fruits of C. sativa (Tharandt Botanical Garden, Germany) have the largest diameter – 2.030 ± 0.076 cm. C. sativa seeds have the highest germination rate - 91.3%, the smallest – in C. dentata – 38.1%. Seed germination of C. “dentata” (cf. C. dentata × C. sativa) is rather high – 63.2%. Seedlings of C. dentata have reddish, thin stems; leaves of the lower formation, including 2, crescent-shaped, about 0.5 cm long, arranged alternately; the first true leaves are similar to the leaves of adult plants. On average, the growth of C. dentata seedlings (MBG RAS Natural Flora Exposition) for the first week was 2.063 ± 0.050 cm, for the second week – 9.375 ± 0.565 cm. C. sativa, C. dentata and their hybrid are promising for further seed propagation and introduction research in the conditions of central Russia.