Vegetative Mass Research Articles

Optimizing the nitrogen application rate and planting density to improve dry matter yield, water productivity and N-use efficiency of forage maize in a rainfed region

Appropriate nitrogen (N) fertilization and planting density management are critical for efficient production of grain maize (Zea mays L.) and for environmental protection. However, the optimal N fertilization and planting density is still not established for forage maize that is cultivated to promote its vegetative growth and utilized for the above-ground vegetative mass. A two-year field experiment was conducted in the rainfed semiarid region of the Chinese Loess Plateau during the 2021 and 2022 growing seasons. The effects of N application rates and planting densities on the dry matter yields and the water- and N-use efficiencies of forage maize were studied. The experiment includes four N application rates (0, 90, 180, and 270 kg ha−1) and three plant densities (70000, 90000, and 110000 plants ha−1), covering the conventional practices of local farmers. The treatments were organized in a randomized complete block design with four replications. Averaged over the three plant densities, N application rate of 180 kg ha−1 resulted in the maximum average aboveground dry matter yield (18.6 t ha−1), crop N accumulation (228.5 kg ha−1), dry matter water productivity (51.9 kg ha−1 mm−1), and dry matter precipitation productivity (62.9 kg ha−1 mm−1) over the two years. Moreover, increasing N application rates significantly increased the soil nitrate-N accumulation (0–200 cm) but reduced the partial factor productivity of applied N fertilizer. Across the three plant densities, the two-year average soil nitrate-N accumulation was 12.6, 32.1, and 75.7 % higher with 90, 180, and 270 kg N ha−1 compared to no N treatment, respectively. The highest soil nitrate accumulation under 270 kg ha−1 N application rate in 2021 (229.5 kg ha−1) and in 2022 (329.7 kg ha−1) may cause severe nitrate leaching loss and potential soil water contamination, driven by intensive rainfalls. Averaged over the four N rates, planting density of 110000 plants ha−1 increased the crop N accumulation and PFP by 21.2 % and 15.8 % in 2021, compared to 70000 plants ha−1, respectively. The interaction of N application and planting density significantly affected the aboveground dry matter yield, crop water consumption, dry matter precipitation productivity, and crop N accumulation in 2021, but the effect was non-significant in 2022. Based on these findings, application of 180 kg N ha−1 and planting density of 110000 plants ha−1 are suggested as an efficient management strategy for improving productivity of forage maize and soil water and N resources utilization in the arid region of the Loess Plateau and similar areas.

Enhanced fig tree production through endomycorrhizal fungi inoculation: A nursery study on tree cuttings derived from the Ifrane Region, Morocco

The mycorrhizal association represents a crucial symbiotic bond necessary for the vitality of the majority of plants. This report aims to investigate the impact of endomycorrhizal fungi on the production of fig trees from cuttings. The research took place in a nursery environment by inoculating fig cuttings sourced from three sites in Morocco with a composite inoculum of arbuscular mycorrhizal fungi (AMF). The mean root and vegetative masses of the inoculated plants after 140 days were 33.1 g and 35 g compared with 1.8 g and 6.4 g in the control. The mean shoot length and number of leaves developed from treated cutting were 98.5 cm and 17, respectively 29 cm and 4 leaves in control. Thus, the newly formed roots showed a well-established mycorrhizal colonization and contained different structures characteristic of arbuscular endomycorrhizae: arbuscules, vesicles, endophytes, hyphae and spores. The frequency and intensity of root mycorrhization were approximately 80% and 15.5%, respectively. The contents of arbuscules and vesicles were 2.5% and 5.5%. The study of formed spores showed a combination of 52 spores per 100 g of soil, belonging to 11 species and 3 genera: Glomus, Acaulospora and Rhizophagus with dominance of the genus Glomus (85%). Glomus macrocarpum and Glomus deserticola were the most abundant species, appearing at 30.77% and 19.23%, respectively. The results demonstrate a pronounced stimulating effect on both root formation and vegetative shoot development in the inoculated cuttings. Specifically, the early inoculation of fig cutting with the AMF inoculum significantly enhanced rhizogenesis end root system development. Consequently, the gradual establishment of mycorrhizal symbiosis at the root level of inoculated plants led to good development of the root mass and the vegetative mass. The inoculated plants showed good root and vegetative mass development due to the installation and the progressive development of mycorrhizal symbiosis at their roots.

Extraction and chemical constituents of the essential oils from Rosmarinus officinalis L. and Corymbia citriodora

The essential oils of Rosmarinus officinalis L. and Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson leaves have chemical constituents with fungicide potential. The objective of this work was to determine the yield and the main chemical compounds of the essential oils of these species. Plants of the two species were georeferenced and collected in municipalities of Rio Grande do Sul, and identified in the Botany Laboratory of UNIJUÍ. The essential oils were extracted by hydrodistillation and the yield was based on fresh vegetable mass. The analyses of the chemical constituents were determined by CG-MS. A yield of 0.49% was obtained for R. officinalis and of 1.54% for C. citriodora. Similar to other studies, the major constituents of rosemary essential oil were camphor, 1,8-cineol, canfene and α-pineno, and the ones of eucalyptus essential oil were citronelal, isopulegol and citronelol. It is concluded that the chemical constituents are similar to those reported in the literature and the essential oil yield of the species is low and dependent on external conditions.

LACTIC ACID BACTERIA CONTRIBUTING TO UPGRADE FODDER QUALITY

A solid nutrition stock lays the basis for contemporary animal husbandry. Application of lactic acid bacteria and their metabolites to raise the standards of feed rations as ingredients of pre- and probiotic additives, is an evolutionarily grounded basic microecological technique to uphold health status and realize genetic potential of superproductive farm animals. Throughout several decades the studies are under way at the Institute of Microbiology of the National Academy of Sciences of Belarus on isolation of lactic acid bacterial strains from various natural sources, investigation of their properties, characterization of produced bioactive agents and elaboration of the derived technologies of manufacturing diverse microbial preparations for various purposes. Specially selected lactic acid bacteria isolated from various plant sources in Belarus and adapted to local ecological environment are distinguished by intense growth, capacity to compete with other microbial species, active acidogenesis, rapid acidification of substrates down to pH 4.2 or even lower, acid resistance, a broad spectrum of fermented carbohydrates (ability to utilize hexoses, pentoses, oligo- and polysaccharides) and they served as appropriate constituents of liquid biocompositions (Lacsil, Lacsil-M), dry preparation Lacsil-MS designed to improve quality of ensiled vegetable materials. Lacsil-MS2 concentrate includes homo- and heterofermentative lactic acid bacteria consuming a wide range of carbohydrates: hexoses, pentoses, oligo- and polysaccharides, including major reserve polysaccharides of cereals and legume grasses (starch, polyfructosides). Supply of fastly growing coccoid forms of lactic acid bacteria enables to intensify the process of lactic acid fermentation at the earliest stages and swiftly reduce pH of vegetable mass. Addition of strains with elevated antagonistic activity ensures the suppression of growth of microorganisms responsible for spoilage of fodder. Upgrading consortium composition with heterofermentative lactic acid bacteria and propionic acid bacteria prevents spoilage of fodder caused by air access in the course of feeding procedure. Production by the selected microbial cultures of a set of enzymes (amylase, α-galactosidase, β-glucanase, pectinase, etc.) capable to hydrolyze hardly digestible oligosaccharides, starch-containing and non-starchy polysaccharides of plant substrates, promotes enhanced bioaccess, better assimilation, increased alimentary and energy value of feed rations. Evaluation of technology of producing feed additive based on lactic acid bacteria possessing high α-galactosidase activity acquired top relevance due to the need to eliminate deficit of fodder protein in farm rations by replenishing the share of legumes (alfalfa, lupine, soy, peas, etc.). Introduction of such feed additive incorporating lactic acid bacteria, fermenting recalcitrant oligo- and polysaccharides with α(1→6) glycoside bonds allows to raise digestibility and assimilation of proteins and carbohydrates, to increase the input ratio of legume components into composite fodder formulas, to rule out intestinal disorders (gut meteorism), contributing thereby to farm stock productivity. It was found that application of preparations comprising selected lactic acid bacteria resulted in economy of fodder expense up to 20% per each kilo of live weight increment, to augment average daily body gains by 9-12%, to increase productivity of lactating cows by 5-10%, and to diminish by 5.0% losses of digestible protein as compared with imported product analogues.

SPATIAL DISTRIBUTION AND ASSESSMENT OF PUBLIC GREEN SPACES IN AN URBAN SETTLEMENT

The article examines the current land use of green spaces as an integral part of the urban economy through the example of a city in central Ukraine, Kropyvnytskyi. It analyses the regulatory framework for the functioning of green spaces. The study also includes an analysis of the geospatial distribution of public green spaces and their structure by number and area in the regional centre. The authors estimate the green areas covered with tree plantations based on vegetative indicators using remote sensing data. The Normalised Difference Vegetation Index (NDVI) allowed for clarifying the boundaries of green areas, their area, and the density of green mass of vegetation. This index helps to identify the spatial-temporal trends of vegetation, which are necessary to support scientific-grounded management decisions for city governance. The results of determining the NDVI are presented in the example of the park-monument of landscape art ‘Dendropark’. For vegetation in good condition, its value exceeds 0.7, corresponding to 58 % of the area. The Shannon Diversity Index has been used to assess the distribution of land use types in the green areas of general use. We identified six types of green area land use in Kropyvnytskyi city and performed the index calculations according to these types of land use. The calculation of the provision of public green spaces for city residents confirmed its low value compared to the standards. The research’s results determined that Kropyvnytskyi city needs to create new green zones, preserve existing ones, inventory, and develop a database of all green areas. Planting areas of new residential buildings and applying the experience of other countries to increase green areas due to alternative landscaping types (vertical landscaping, green roofs, and others) will allow for an expansion in the green areas of settlements, especially in large cities. The practical importance of the research results is their potential use for creating a strategy to develop and preserve green plantings in the city of Kropyvnytskyi for future years. Keywords: vegetation index, land use, diversity index, green areas, parks.

Impact of planting density and shoot thinning on alstroemeria flowering, soil attributes and cost economics

A field experiment was conducted to assess the impact of various planting densities and levels of shoot thinning on cut flower yield, quality, soil chemical properties and cost economics in the commercially cultivated alstroemeria cultivar 'Capri'. The experiment involved three planting densities (4, 6 and 8 plants/m2) along with three shoot thinning levels (10 %, 20 % and 30 %). It was observed that higher planting density (4 plants/m2) promoted the length of cut stem, early bud formation, and flowering, optimal quality parameters, including maximum stem thickness, cut stem weight, floret quantity/stem, floret size, number of flowering stems/plant (yield) and vase life. Exclusive use of higher vegetative mass removal (30 % shoot thinning) was found to improve quality parameters such as the length of cut stem, number of flowering stems, stem thickness, weight of cut stem, floret quantity/stem, floret size, vase life, and early flowering. Soil samples were collected from each treatment and the consequent lab analysis revealed that the lower planting density and shoot thinning level resulted in maximum soil organic carbon, nitrogen, phosphorous and potassium content. In conclusion, planting density of 4 plants/m2 and 30 % shoot thinning emerged as the optimal combination for enhancing quantitative parameters in commercial alstroemeria cultivation. The study underscores the importance of strategic planting practices and vegetative mass management for maximizing yield and quality in alstroemeria production, along with ensuring higher economic returns.

Accumulation of Chemical Elements in the Vegetative Mass of Energy Cultures Grown on Gray Forest Soils in the Western Forest Steppe of Ukraine

Accumulation of Chemical Elements in the Vegetative Mass of Energy Cultures Grown on Gray Forest Soils in the Western Forest Steppe of Ukraine

Elicitation of potato plants to increase their resistance against Soft Rot Pectobacteriaceae bacteria

AbstractThe investigation aimed to assess three methods for inducing resistance in Solanum tuberosum L. (potato) plants against Soft Rot Pectobacteriaceae (SRP) bacteria. The approaches involved the incorporation of elicitors into the in vitro nutrient medium during plant cultivation, pre-planting of seeds soaked in water-containing elicitors, and irradiating in vitro cultivated potato plants with 21 kJ/m2 of ultraviolet C light (UVC). The research validated the authors’ hypothesis, that the use of specific elicitors and UV-C light could induce resistance in potato plants against SRP bacteria, identifying the most effective elicitation technique for potato plants under experimental conditions. Two elicitors, specifically 50 μM salicylic acid and 250 μg/mL proline, were determined to be the most potent under experimental conditions. Supplementation of the Murashige and Skoog medium (MS) with 50 μM salicylic acid resulted in 21% of infected plants exhibiting no symptoms of infection on the 14th-day post-inoculation, and all plants treated with 10, 30, 35, 40, 45, or 50 μM of salicylic acid displayed a diminishing rate of infection progression. Plants growing with 25 µM SA were visually characterized by faster growth rates and higher vegetative mass relative to both control and test variants. Similarly, the incorporation of 250 μg/mL proline into the MS medium caused a response with 37.5% of plants showing no disease symptoms on the 14th day post-inoculation.

Young dove trees tend to invest more biomass in vegetative and reproductive organs than old trees at the twig level

Research on the functional traits of twigs is of great significance to clarify the plant life-history strategies, especially for endangered plants. However, little attention has been given to the environmental adaptation strategy of different age twigs. The dove tree (Davidia involucrata Baill.), a relict and critically endangered Chinese species, was employed as a model species. Total lamina mass and area, stem mass and length, total bract mass and area, and total petiole mass were measured for 100 current-year terminal twigs (50 per age group) from old and young dove trees in Pingwu County, Sichuan, southwest China. Then, the scaling relationships within the twig were determined using the standardized major axis (SMA) regression method. Our results showed that the significantly positive correlations among traits of D. involucrata twigs, and scaling relationships between these traits are different between the two age groups. At the twig level, isometric scaling relationships exist between stem mass and lamina size (or bract size) and between total lamina mass and total lamina area (or total petiole mass). In contrast, allometric scaling relationships exist between lamina size (total mass and area) and stem length (with a common slope > 1), and between total lamina mass and total petiole mass (with a common slope < 1). For a given stem mass, stem length and bract area, young trees have larger total lamina mass and total bract mass, larger total lamina mass and area, and larger total bract mass than old trees, respectively. The results suggest that young trees tend to have more vegetative and reproductive organ mass per unit of supporting organ mass than old trees to meet their rapid growth needs.

Значение бактериальных удобрений в формировании урожая зерновых бобовых культур

Abstract. One of the directions of modern agricultural production is the biologization of agriculture, which provides for a wider use of biological preparations and bacterial fertilizers. The use of bacterial fertilizers restores the fertility of the soil, contributes to increasing the yield and quality of agricultural products. The purpose of the study is to establish the effectiveness of the use of bacterial fertilizers in the cultivation of grain legumes. Methods. The research was carried out for three years, observations and records were carried out according to the generally accepted methodology of field experience. Results. The effectiveness of the application of top dressing with bacterial fertilizers “Azotovit” and “Fosfatovit” in the cultivation of grain legumes (soybeans, lentils) on light gray forest soils has been established. The use of “Fosfatovit” accelerated the ripening of soybeans for 4 days, lentils for 5 days, “Azotovit” influenced the formation of vegetative mass, increasing the number of leaves and the weight of the plant. An increase in the microbiological activity of the soil was noted when applying top dressing with bacterial fertilizers, the maximum value was obtained in variants with joint top dressing with “Azotovit” and “Fosfatovit”, in the experiment with soy, it averaged 72.1 %, in the experiment with lentils 81.5 %. The maximum increase in soybean yield was provided by fertilizing with “Fosfatovit” for an average of 3.97 t/ha over three years. Fertilizing with “Azotovit” and “Fosfatovit” had the greatest effect on lentils, in this variant the yield increased by 0.59 t/ha, or 32.4 % compared to the control. Top dressing with bacterial fertilizers contributed to an increase in crude protein and crude fat in soy and lentil grains. The scientific novelty of the research is to establish the effectiveness of the application of top dressing with bacterial fertilizers in the cultivation of soybeans and lentils in the conditions of the Chuvash Republic.

Effect of fertilizers and meliorants on the value of soil acidity of sod-podzolic light loamy soil, yield and chemical composition of the green mass of spring rapeseed (according to laboratory and vegetation experience)

Under controlled conditions of laboratory vegetation experience based on very strongly acidic sod-podzolic sandy loam soil, a comparative study of the fertilizing value and reclamation properties of complex mineral fertilizers (azofoska andAPAVIVA) and meliorants of a carbonate nature was carried out: conversion chalk (CC), gravel screening (GS), dolomite (DM) and dolomitized (DIM) limestone flour, as well as silicate nature–blast furnace slag (BFS) and hydroxide nature–Mg(OH)2.Culture–spring rape of theLexus variety.It was shown that the reclamation effect obtained as a result of the use ofBFSand meliorants of a carbonate nature differed little from each other and after 45 days of plant cultivation were insignificant.Magnesium hydroxide did not have a reclamation effect.The yield data of the vegetative mass of rapeseed after harvesting are given.It is shown that the chemical composition of meliorants had a significant effect on the formation of the elemental composition of plants.

Influence of Selenium on the Yield and Content of the Amino Acid Composition of Spring Wheat Grain under Optimal Conditions of Water Supply and during Drought

In model experiments in soil culture, the effect of various methods of applying sodium selenite on the formation of yield and amino acid composition of grain varieties of spring wheat Zlata and Ester, depending on water supply conditions, was studied. Sodium selenite was introduced by pre-sowing seed treatment and leaf treatment of vegetative plants. The study simulated optimal water supply conditions and soil moisture deficiency during the critical period of plant growth. The role of selenium in the regulation of the production process and the formation of the amino acid composition of spring wheat grain was studied. It was found that the production process of wheat plants, both under optimal water supply and in drought conditions, depended on the method of application of selenium and the varietal characteristics of spring wheat. The results allowed us to assume that selenium activated the attenuating ability of the ear by enhancing its acceptor properties. Under these conditions, the grains were better provided with assimilates. this made it possible to form the maximum possible yield of wheat grain. In conditions of drought, during leaf treatment of plants with sodium selenite, favorable conditions were created for the formation of reproductive organs of wheat, which stimulated the restoration of the processes of assimilate outflow from the vegetative mass into the forming grains. This made it possible to influence production processes and reduce the depression of wheat crop formation. The use of selenium revealed an increase in the total content of key amino acids, which had a significant effect on the antioxidant status of plants and contributed to the realization of their adaptive potential. The positive effect of selenium on the content of a number of amino acids, including on the assimilation of methionine, was revealed, which was probably due to the synthesis of selenomethionine, since the ways of their formation are similar and it is not possible to separate them. The greatest effect of selenium was observed in the cultivation of wheat of the Zlata variety compared with wheat of the Ester variety, which was determined by varietal differences inherent genetically and the unequal protein content in the grain.

Приемы увеличения продуктивности горчицы сарептской яровой – культуры многоцелевого назначения

In 2021–2023, we studied influence of compound fertilizers on seed productivity, yield of green and dry biomass, oil content in seeds and oil yield of spring brown mustard on fields of the V.S. Pustovoit All-Russian Research Institute of Oil Crops (Krasnodar), on leached black soil of Western Ciscaucasia. Foliar fertilizing with microfertilizers had a positive effect. Comparing to the variant without fertilizer application, these traits increased: seed yield – by 0.29–0.58 t/hа, green mass – by 8.8–10.2, dry biomass – by 1.4–1.8, oil yield – by 0.15–0.26 t/hа, oil content in seeds – by 0.8–1.6 %. However, efficiency of foliar fertilization was controversial. Thus, to obtain the highest seed yield (2.03 t/hа) and oil yield (0.86 t/hа) of spring brown mustard, it is necessary to conduct foliar fertilizing with a complex fertilizer Brassica in a dose of 2 l/hа in a phase of stem growth. The highest vegetative mass of mustard (33.6 t/hа) is formed at foliar fertilization with a fertilizer Vegetative in a dose of 2 l/hа in a phase of crop seedlings. The subsequent application of the complex fertilizer Vegetative in a dose of 2 l/ha in a phase of seedlings and the complex fertilizer Brassica in a dose of 2 l/ha in a phase of stem growth allowed obtaining yield of dry bi-mass of spring brown mustard by 0.4 t/hа higher comparing to other foliar fertilizations.

Damage to potato tubers by cut worms in grain-grass root-crop rotation in the north-west of the Russian Federation

The paper presents the results of long-term monitoring of potato tuber damage by caterpillars of cut worms and study of the factors determining it. The research was carried out in grain-grass root-crop rotation in the north-west of the Russian Federation. In recent years in the domestic and world scientific literature an increase in the pest rate of cut worms on potato plantings has been observed, therefore, it is relevant to identify the factors contributing to a significant limitation of damage to potato tubers by the caterpillars of cut worms. According to the results of the studies conducted in the period 2012–2022, it was determined that the damage to potato tubers by caterpillars of cut worms varies widely – from 0.5 to 15.9%. Weather conditions have the strongest influence on tuber damage by cut worms (influence share – 24.3%). The period from planting to flowering of potatoes is determinant, which is confirmed by statistical treatment (r = 0.65, p &lt; 0.05). Increase of tuber damage by cut worms is promoted by hydrothermal conditions during this period, corresponding to the HTC 2.1–2.3, as well as weeding of plantings with perennial dicotyledonous species and some small perennial species. The influence of vegetative mass of the whole set of growing weed vegetation was expressed by a correlation coefficient equal to 0.14 (p &lt; 0.05), including density and mass of perennial dicotyledonous species – 0.11 (p &lt; 0.05) and 0.13 (p &lt; 0.05). One of the factors that significantly reduce damage to potatoes by this pest is preplanting treatment of tubers with insectofungicides. In combination with the use of herbicides, it provided a 56.8% reduction in the proportion of tubers damaged by cut worm caterpillars in the harvested crop. At the same time, application of mineral fertilizers, change of the forecrop in crop rotation and cultivation of potato varieties with different resistance did not lead to a reliable decrease in damage of tubers by caterpillars of cut worms.

Influence of humic preparations on the development of honeysuckle in the forest steppe of Western Siberia

Blue honeysuckle is a winter-hardy and unpretentious crop; in folk medicine, its berries and juice are used for hypertension, anemia, and intestinal disorders. The environmental situation and the general rise in prices of pesticides and mineral fertilizers stimulate the choice of alternative technologies and the use of biological plant protection products, growth stimulants, and bacterial fertilizers. In this regard, our research aimed to study the effect of various humic preparations on the growth and development of green cuttings of blue honeysuckle variety Berel. This variety has a medium ripening period, gives a high yield, is slightly crumbling, and is highly winter-hardy. The research was carried out in the Novosibirsk region on the territory of the Agro Seed Company in 2019 - 2021. The average annual growth and general condition of blue honeysuckle plants of the Berel variety were determined according to generally accepted methods. Data analysis showed that all studied indicators of honeysuckle plants are greatly influenced by the year’s conditions when the difference between years reaches 25 - 30%. In addition, it was found that all the studied drugs positively affect the growth and development of plants and, in particular, the survival rate and overwintering of green honeysuckle cuttings (up to 45%). Thus, the ZhT “Ekozhizn” preparation provided better survival and overwintering of plants. Cytohumate had a better effect on the development of vegetative mass, but in terms of survival and overwintering, it was inferior to using the ZhT “Ecozhizn” preparation.

Spatial variation in grassland vegetation and herbage mass in the Ejina oasis along the Heihe River in the southern Gobi Desert, China

AbstractOur study area, Ejina, is located in the southern Gobi Desert, Inner Mongolia, China, where the annual precipitation is &lt;50 mm and the annual potential evaporation is &gt;3,600 mm. The Heihe River flows from the Qilian Range through the study area, and the desert landscape along the river includes oases formed by forests and grasslands. We established a survey area of approximately 1.5 ha in grassland facing a seasonal swamp, a branch of the Heihe River. We posed the following questions in this desert grassland: (1) how do soil water content (SWC) and salinity change with distance from the riverbank? (2) How do vegetation, aboveground biomass, and species richness change with distance from the riverbank? (3) How much can be supplied to grazing animals, and how many animals can be grazed? Our results indicated that (1) the SWC is high within 20 m of the riverbank and low beyond 20 m, the standing biomass is positively correlated with SWC, but there was no evidence of a correlation between salinity and distance to water; the electrical conductivity was high both inland and adjacent to the riparian swamp. (2) Vegetation could be classified to six classes, following a gradient from the riverbank (swamp margin) to the dry inland area beyond 20 m from the riverbank. Species richness and aboveground biomass were highly correlated. Classification result led us to recommend that generalist species tolerant of the distinct moisture gradient in the site be used in restoration efforts. (3) Per‐hectare aboveground biomass was 478.93 dry weight (dw) kg, 321.2 ha of equivalent grassland would be required to graze 100 goats annually.

Phenological evolution in annual plants under light competition, changes in the growth season and mass loss.

Flowering time is an important phenological trait in plants and a critical determinant of the success of pollination and fruit or seed development, with immense significance for agriculture as it directly affects crop yield and overall food production. Shifts in the growth season, changes in the growth season duration and changes in the production rate are environmental processes (potentially linked to climate change) that can lead to changes in flowering time in the long-term due to selection. In contrast, biomass loss (due to, for example, herbivory or diseases) can have profound consequences for plant mass production and food security. We model the effects of these environmental processes on the flowering time evolutionarily stable strategy (ESS) of annual plants and the potential consequences for reproductive output. Our model recapitulates previous theoretical results linked to climate change and light competition and makes novel predictions about the effects of biomass loss on the evolution of flowering time. Our analysis elucidates how both the magnitude and direction of the evolutionary response can depend on whether biomass loss occurs during the earlier vegetative phase or during the later reproductive phase and on whether or not plants are adapted to grow in dense, competitive environments. Specifically, light competition generates an asymetric effect of mass loss on flowering time even when loss is indiscriminate (equal rates), with vegetative mass loss having a stronger effect on flowering time (resulting in greater ESS change) and final reproductive output.

The influence of metal nanocarboxylates on the nitrogen-fixing activity of symbiotic soybean systems grown under field conditions

Background. Numerous scientific and industrial studies have proven the high effectiveness of using micronutrients in nanoscale form in agricultural crop cultivation technologies. Among them, special attention is drawn to soybeans, which hold a leading position in terms of sown areas among other leguminous crops in the country. They can provide up to 70 % of their own nitrogen needs through the fixation of its molecular form from the atmosphere in symbiosis with Bradyrhizobium japonicum nodulating bacteria. New methods of molecular biology, biotechnology, and genetic engineering, along with classical methods of microbiology, plant physiology, genetics, and agrochemistry, allow for addressing both fundamental questions regarding the characteristics of formation and functioning of legume-rhizobial systems, and practical approaches to correcting the interactions between symbiotic partners with the aim of creating highly effective symbioses. Therefore, research aimed at significant increasing the current level of biological nitrogen fixation and adapting symbiotic systems to negative environmental factors is currently relevant. The use of nanotechnology, in particular, the study of the effect of iron, germanium, and cobalt nanocarboxylates on the formation and functioning of the soybean-rhizobial symbiosis under field conditions in combination with seed inoculation with rhizobial bacteria may be promising. Materials and Methods. The objects of the investigation were symbiotic systems created with the participation of the Almaz variety of soybean and the Bradyrhizobium japonicum B1-20 rhizobacteria, and with the introduction of nanocarboxylates of iron (Fe), germanium (Ge) and cobalt (Co) into their cultivation medium. Physiological, microbiological, biochemical, and statistical research methods were used. Results. It was found that under field conditions, before the pod formation stage, the vegetative mass of soybean plants inoculated with rhizobial bacteria with the introduction of nanoparticles of carboxylates of iron, germanium, or cobalt into their cultivation medium was at the level of control plants or slightly exceeded them. It has been shown that under the effects of chelated micronutrients, the number of root nodules increased compared to control plants during the flowering and pod formation stages, and their mass was greater from the three trifoliate leaf stage, which ensured efficient functioning of the legume-rhizobial symbiosis. It has been noted that the used metal nanocarboxylates promote active functioning of the symbiotic apparatus in soybean plants, as an increase in nitrogen-fixing activity was observed at the stages of three trifoliate leaf development and flowering, ranging from 26–70 % depending on the microelement used. Conclusions. During field cultivation of soybeans, the effectiveness of pre-sowing seed inoculation with Bradyrhizobium japonicum B1-20 rhizobia was demonstrated through the introduction of iron, germanium, or cobalt nanocarboxylates into their cultivation medium. This opens up opportunities for increasing the efficiency of symbiotic systems of soybeans.

EFFECTS OF MINERAL FERTILIZERS ON WINTER GARLIC PHYSIOLOGICAL AND BIOCHEMICAL PARAMETERS AND PERFORMANCE

Purpose. To improve elements of winter garlic cultivation technology in the Right-Bank Forest-Steppe of Ukraine. The study was intended to locally apply mineral fertilizers at different doses and to assess their effect on the winter garlic yield. Methods. Field, statistical, computational, analytical, laboratory. Results. The study demonstrated that local application of mineral fertilizers influenced quantitative and qualitative characteristics and increased the yield of winter garlic cv. 'Prometei'. The largest vegetative mass of winter garlic was formed at mineral fertilizer doses of N10P10K40 and N13P40K13; in these experimental variants, plants were 38.6–38.0% taller than the control ones; the leaf area increased by 110.7–115.2 cm2/plant. At mineral fertilizer doses of N30P10K10 and N20N20N20, the parameters were slightly lower; however, plants were 37.3 and 36.5% taller than in the control, respectively, and the leaf area increased by 40.5–42.7 cm2/plant. The application of fertilizers during the winter garlic cultivation helped to increase the yield. The best results were obtained with local fertilization at N10P10K40 and N13P40K13: 7.7–5.9 t/ha more was harvested than in the control. Mineral fertilizer doses of N30P10K10 and N20N20N20 raised the yield by 5.1 and 3.1 t/ha, respectively. Conclusions. Thus, in the study of the effects of different doses of mineral fertilizers on the winter garlic performance, it was shown that the largest vegetative mass was produced at N10P10K40 and N13P40K13: in these experimental variants, plants were 6.9 and 7.9 cm taller than control ones, respectively, and the assimilation surface increased by 110.7–115.2 cm2/plant. Positive changes were observed in the N30P10K10 and N20N20N20 experiments: plants were 5.7 and 4.3 cm taller, respectively, and the leaf area increased by 40.5–42.7 cm2/plant. The application of fertilizers during the winter garlic cultivation helped to increase the crop yield. The best results were recorded when mineral fertilizers were applied at doses of N10P10K40 and N13P40K13: the crop yield was 7.1 and 9.4 t/ha, respectively. The mineral fertilizer doses of N30P10K10 and N20N20N20 significantly increased the yield (by 5.8–4.6 t/ha).

Identification of Vegetation Surfaces and Volumes by Height Levels in Reservoir Deltas Using UAS Techniques—Case Study at Gilău Reservoir, Transylvania, Romania

The hydrophilic vegetation from reservoir deltas sustains rapid expansions in surface and important increases in vegetal mass against a background of a significant influx of alluvium and nutrients from watercourses. It contributes to reservoir water quality degradation and reservoir silting due to organic residues. In this paper, we propose an evaluation method of two-dimensional and three-dimensional parameters (surfaces and volumes of vegetation), using the combined photogrammetric techniques from the UAS category. Raster and vector data—high-resolution orthophotoplan (2D), point cloud (pseudo-LIDAR) (3D), points that defined the topographic surface (DTM—Digital Terrain Model (3D) and DSM—Digital Surface Model (3D))—were the basis for the realization of grid products (a DTM and DSM, respectively). After the successive completion of the operations within the adopted workflow (data acquisition, processing, post-processing, and their integration into GIS), after the grid analysis, the two proposed variables (topics) of this research, respectively, the surface of vegetation and its volume, resulted. The data acquisition area (deriving grids with a centimeter resolution) under the conditions of some areas being inaccessible using classical topometric or bathymetric means (low depth, the presence of organic mud and aquatic vegetation, etc.) has an important role in the reservoirs’ depth dynamics and reservoir usage. After performing the calculations in the abovementioned direction, we arrived at results of practical and scientific interest: Cut Volume = 196,000.3 m3, Cut 2D Surface Area = 63,549 m2, Fill Volume = 16.59998 m3, Fill 2D Surface Area = 879.43 m2, Total Volume Between Surfaces = 196,016.9 m3. We specify that this approach does not aim to study the vegetation’s diversity but to determine its dimensional components (surface and volume), whose organic residues participate in mitigating the reservoir functions (water supply, hydropower production, flash flood attenuation capacity, etc.).