Automation and digitalization of healthy fruit and berry plants reproduction

High-quality planting material is a condition for increasing productivity and labor productivity in the cultivation of agricultural products. High-quality planting material is material that is free from harmful pathogens. The process of plant healing requires significant time and material costs. However, with the proper organization, plant healing can be significantly accelerated and cheapened. The main condition for accelerating this process is maximum automation and digitalization of all stages of clonal micropropagation. The article shows the results of many years of work on the cultivation of healthy planting material. Variants of possible improvement of planting stock recovery are proposed with the introduction of the necessary hardware and software at specific stages of recovery and reproduction.

Effects of Mechanical Site Preparation, Planting Stock, and Planting Aids on the Survival and Growth of American Sycamore in a Marginal Old Field Riparian Restoration

Survival and growth of planted tree species are common indices used to evaluate success of wetland restoration efforts used to compensate for wetland losses. Restoration efforts on marginal agricultural lands have typically resulted in less than satisfactory survival and growth of desired tree species. In an attempt to determine the effects of bottomland hardwood silvicultural methods on the survival and growth of pioneer tree species, this study evaluated combinations of five mechanical site-preparation techniques (mound, bed, rip, disk, pit), four levels of planting stock (gallon, tubeling, bare root, and direct seed), and three planting aids (mat, tube, none) on the four-year survival and growth of American sycamore planted in an old field riparian area in the Piedmont of Virginia. After four growing seasons, results indicated that mounding mechanical site preparation combined with gallon (3.8 L) planting stock provided the most positive influences on mean survival (100%), height (4.72 m), and groundline diameter (9.52 cm), and resulted in the greatest aboveground dry biomass accumulation (5.44 Mg/ha/year). These treatments may be economically viable for restoration and mitigations efforts, and could offer other economic alternatives such as short-rotation woody crops, which might make restoration efforts in marginal old field areas more attractive to private landowners.

Overwinter Storage of European Beech and Norway Spruce Planting Stock: Effect of Different Methods and Temperature Conditions

The aim of this research was to compare methods of overwinter storage of forest tree species planting stock and to specify of the optimal and the minimal temperature for freezing. Planting stock of European beech and Norway spruce were stored three times over a period of dormancy (2015/2016, 2016/2017, 2017/2018) (1) in freezers, (2) in an air-conditioned warehouse, (3) in a cave and (4) in soil (bare-rooted plants) and at a holding area (containerized plants), i.e., an open storage. During storage, the vitality of plants was determined using the root electrolyte leakage (REL) parameter, and in 2016 also by restoring growth in a sample of plants. The stored plants were always planted in a forest research plot in the spring and their basic morphological parameters and mortality were evaluated at the end of the growing season. The most suitable temperature for storage of both bare-rooted and containerized beech and spruce was in the range from −3.4 °C to −1.7 °C. The plants after overwinter storage showed no significant mortality after planting–they showed a high vitality of the fine roots and a normal increment, and were not damaged by frost, mold or other negative factors during storage.

Effect of Host Plants and Potting Mixture on Growth of Sandalwood Seedlings at Nursery Stage

Sandalwood (Santalum album L.) is one of the most valuable commercially cultivated aromatic species throughout the world. However, the availability of quality planting stock isthe current bottleneck in its establishment on large scale. The major problems, noticed during quality planting stock production in nurseries are scarce knowledge about host-parasite relationship and use of appropriate potting mixture apart from its seed germination. In this regard two experiments were carried out at the College of Forestry, Ponnampet during 2020-2021 to identify suitable host plant and potting mixture. Growth parameters were recorded after 90, 180 and 270 days of transplanting sandal seedlings into treatments. After 270 days of transplanting, the host plant A. lebbeck recorded higher survival of sandal seedlings (81.89 %) and the host plant C. junghuhniana had higher height growth (10.40 cm) with collar diameter 2.33mm. Potting mixture sand, soil, vermicompost, G. intraradices with C. Junghuhninana found effective for height (18.25 cm) and collar diameter (2.58 mm).

Silvicultural Production as a Basis for Continuity of Forest Management

Currently, the principle of sustainable use of forests is a fundamental direction in the management of natural resources. Solving the problems of sustainable development of forestry in the European North involves ensuring the quality reproduction of forest resources. The main parts of silvicultural production are procurement and preparation of seeds; growing planting stock, creation of new stands and agricultural tending of them. The goal of the federal project “Forest Conservation” is to ensure the balance of forest felling and reproduction in the ratio of 100 % by 2024. The emphasis is on the use of ball-rooted planting stock for artificial reforestation. Information gap on the long-term prospects of its use, as well as the lack of data on the results of long-term observations of growth and condition of forest crops created by seedlings with a lump of substrate, and comparison of such seedlings with traditional planting stock, especially in northern conditions, update the topic of research. The research purpose is to identify conditions for obtaining high-quality planting stock, as well as to assess the possibility of successful restoration of pine on felling sites in the north of the European part of Russia by creating forest crops using regional intensive technologies, based on the results of long-term technologies. The main objects of observations are nurseries of the region, the procedures used in them and the experimental planting of pine trees in the Kargopol and Arkhangelsk forestries in 2000–2001. Preservation, diameter, height, and volume were determined in dynamics in the areas of crops created from various types of planting stock (seedlings, plantlet, ball-rooted planting stock). The counts were carried out with several repetitions and dividing plants into healthy, weak and dry. Wood flaws of pine trunks were also noted and natural regeneration was recorded. Based on the research materials, the possibility of successful restoration of pine trees on felling sites in the north of the European part of Russia is shown using regional intensive technologies for the production of various planting stock and the creation of forest crops. This will reduce the period of transfer of young trees to natural conditions and increase the productivity of plantations. Comparison of average diameters and heights for all accounting periods indicates the influence of the type of planting stock and density of planting on the growth and development of trees. During the observation period, plantlets lead in all respects. Their height and diameter is 20–44 % higher than that of yearling seedlings, and in terms of stem volume the difference with other types of planting stock reaches 1.9–2.9 times.

Prosopis velutina (velvet mesquite).

P. velutina was widely introduced around the world intentionally, due to its value as a fuel/fodder species and also an ornamental in some regions. It was widely used by native Amerindians as a source of poles and fuels, and the pods were a valuable source of human and animal nutrition. The month of the year when pods were harvested was commonly named after the tree, indicating its importance. However, its has also spread, both in its native range and where introduced, and its infamy as an invasive species has lead to several governments banning further importation of planting stock, and the risk of introduction is perceived as low. P. velutina is a declared noxious weed in Australia and South Africa, and the genus as a whole is regulated in several other countries. Losses to the livestock industry from P. velutina invasion in its native range, although much less than that caused by the invasion of P. glandulosa, are still considerable. The thorns can also cause injury to livestock, and consumption of the pods, when they may up the bulk of the animal's diet, can lead to ill health and even death. A similar situation to that of the south-western USA exists in Australia and South Africa, where P. velutina is a major weed of rangelands.

Psidium cattleianum (strawberry guava).

Stand establishment using: natural regeneration, planting stock. Vegetative propagation by: cuttings, grafting.

Regulation of water regime of sod-podzolic soil in fruit tree nursery and water distribution pattern in the soil profile under different irrigation regimes

Based on the results of field experiments carried out in the nursery of Michurin garden of Russian State Agrarian University named after K.A. Timiryazev, rational irrigation schedules for apple-tree seedlings of different age (1-, 2- and 3-year-old) were developed and scientifically substantiated. Excess water was diverted from the experimental plot by underground drainage system, and the drip irrigation system was used for watering plants. With its characteristic low rate of water usage and highly frequent irrigation applications it allows the moisture content to be maintained within a narrow range. The effectiveness of irrigation schedules was evaluated by the response of seedling – their biometric characteristics, determining the productivity of apple trees in orchard in future, such as average plant height, stem diameter at 20 cm height, leaf surface area, which were measured. The amount of high-quality planting stock was recorded in each variant as well. In order to btain 1-year-old apple seedlings it is recommended to maintain soil moisture within the range of 70–90% of field capacity (FC). This irrigation schedule results in the maximum amount of standard planting stock (1-st and 2-nd category) – 25.9 thousand seedlings per ha, with the average leaf surface area of 1 468 cm2, trunk diameter – 1.8 cm, plant height – 140 cm. For 2- and 3-year-old seedlings the differentiated irrigation schedule was developed, whereby the moisture content and depth of the wetted layer varies as the root system grows. In the first year of growth soil moisture should be maintained within the range of 70–90% FC in 0–30 cm layer because of the poorly developed root system; for 2- and 3-year-old nurslings soil moisture can be reduced to 60–80% FC in 0–40 cm and 0–50 cm layer respectively. The height of 2-year-old seedlings was on average 174 cm, leaf surface area – 3 715 cm2, stem diameter at 20 cm height was 2.3 cm, the amount of standard planting stock was 25 thousand seedlings per ha. The 3-year-old seedlings reached the height of 214 cm, were characterized by leaf surface area of 5 973 cm2, stem diameter at 20 cm of 2.8 cm, the yield of standard seedlings was also 25 thousand seedlings per ha. Moreover, for two variants of irrigation (60–80% FC and 70–90% FC) moisture distribution contours immediately after irrigation, 24 hours after irrigation and before the next irrigation application were designed. The areas of segments with different moisture content in vertical section of contours were calculated, thus, revealing the character of moisture distribution down the soil profile and allowing performance of comparative characteristic of irrigation schedules. The obtained wetting contours indicate the absence of unproductive losses of irrigation water for infiltration into the underlying horizons when the considered drip irrigation schedules were applied.