Entire Vegetation Period Research Articles

Effectiveness of Bradyrhizobium japonicum inoculation on nodulation dynamics in Glycine max (L.) roots

Bradyrhizobium japonicum bacteria on the intensity of nodulation during nine phenophases (R1-R7) in relation to the isoflavone content in soybean seeds. Nine domestic soybean varieties were sown in three replicates, with Bradyrhizobium japonicum inoculated and non-inoculated seeds. The different morphological characteristics of nodules, the number and mass of nodules were studied during plants’ ontogenesis. The content of individual isoflavones in the sowing seed material was determined using high performance liquid chromatography mass spectrometry (HPLC-MS). The most abundant isoflavone was acetylgenistin in the variety Galeb (2741.4 μg/g), and the highest content of all isoflavones was recorded in the variety Gorštak (8117.7 μg/g). The variety Sava of the inoculated treatment exhibited the highest average values of the nodule mass (21.1 mg) and the highest number of nodules (23.3) in the phenophase, in which 10% of pods reached full length (R4). The average values of mass and number of nodules were calculated for the entire vegetation period, being higher in the inoculated treatment. There was no positive correlation between the content of isoflavones in seeds and the number and mass of nodules. The impact of quantity of isoflavone on nodulation intensity in soybeans was not significant,, which could be related to already saturated soil with nitrogen-fixing bacteria.

Effectiveness of sod and humus soil maintenance and biologized protection in intensive apple orchards (Malus domestica Borkh.) in the south of Russia

Application of intensive technologies in horticulture with a high mechanical and chemical load on soils and fruit plants leads to deterioration of soil properties, environmental pollution, and development of resistance among pathogens and phytophages. In this study, we aim to developing a biologized technology for apple tree cultivation using a sod and humus system of inter-row maintenance and biopreparations based on active strains of microorganisms, entomoacariphages, and pheromones. The research was conducted in 2019-2023 in intensive apple orchards of the central plain-steppe region of Crimea by the methods conventionally used in soil science, agrochemistry, horticulture, and plant protection. The use of a mixture of cereal-legume grasses in combination with microbiological fertilizers based on nitrogen-fixing microorganisms was found to increase apple yields by 11–12 t/ha, or 64 % compared to the control, by increasing the number of fruits and the average weight of one fruit. A positive balance of nutrition elements in soil with an intensity of 135-270 % was established. The efficiency of controlling the number of phytophages and pathogen harmfulness through the integrated use of biological and biotechnical methods was shown. Thus, the “attract-and-kill” method for Cydia pomonella L. pheromones demonstrated a 98 % efficiency along with a reduction in pesticide load to 7.7 kg/ha season by the preparation. Release of phitoseiid mites for control of tetranychus mites by the method of seasonal colonization provides for a reduction and retention of phytophagous population at the economic threshold of harmfulness during the entire vegetation period. The use of fungicides based on pathogenic bacteria of the Bacillus genus and antagonist fungi of the Trichoderma genus against scab is eff ective only in the years unfavorable for the development of the disease. The results obtained form the basis for a biologized resource-saving technology for exploitation of intensive apple orchards. This technology contributes to increased soil fertility, reduced chemical and pesticide load, and increased productivity of horticultural agrocenosis under the conditions of the Crimea and southern Russia.

Influence of preparations on photosynthetic activity of brewing barley (Hordeum vulgare L.) plants and quality indicators of grain

Plant growth regulators and microfertilizers stimulate the accumulation of chlorophyll by plants, increase the photosynthetic activity of chloroplasts and the net productivity of photosynthesis, and contribute to increasing the resistance of crops to diseases and adverse environmental factors. The aim of the work was to study the effect of preparations on the photosynthetic activity the plants of spring barley varieties in order to achieve the proper quality of the grown products. In the research, barley plants of the spring brewing direction of the varieties Sebastian (Seyet Planteforedling I/S, Denmark) and Salomi (SAATEN Union, France) were used, which were treated with plant growth stimulator Vimpel 2, complex microfertilizer ORACUL multicomplex, a mixture of Vimpel 2 + ORACUL multi-complex and control area — water treatment. The article presents the results that show that the content of the sum of chlorophylls a and b in spring barley leaves under the influence of preparations Vimpel 2 and ORACUL multicomplex plays a major role in increasing the productivity of the crop. Accumulation of protein and starch in spring barley grains is one of the most important indicators for growing varieties of brewing value. In all variants of the study, the accumulation of protein in the grain turned out to be within acceptable limits for malting barley (8.75–10.02%), only in the control variant it remained too low. The use of preparations Vimpel 2 and ORACUL multicomplex in a mixture contributes to the accumulation of starch in spring barley grains of both studied varieties. At the same time, treatment with only growth promoter or only micro-fertilizer stimulates the accumulation of starch in the grain compared to the control, but remains at a low level for the brewing industry. The most active growth of the assimilation surface of spring barley plants in all phases of growth was observed after treatment with Vimpel 2 mixture in combination with ORACUL multicomplex. The conducted studies established a significant influence of microfertilizers and growth stimulants on the photosynthetic potential of spring barley crops. During the entire vegetation period of spring barley, the highest photosynthetic potential of crops (FPP) — 859.2 m2/ha×day was determined in the Sebastian variety with the addition of microfertilizer and growth stimulator. The high-quality work of the leaf apparatus of plants is determined by the net productivity of photosynthesis (NPP). The highest PPF index was observed on the Sebastian variety in the variant treated with a mixture of microfertilizer and growth stimulator, which is 27% higher than in the control variant. Therefore, spring barley grain of the required quality can be obtained only under the conditions of optimal combination of the use of preparations of different spectrum of action.

ПОЖИВНИЙ РЕЖИМ І ЗАБУР’ЯНЕНІСТЬ ПОСІВІВ СОРГО ЗЕРНОВОГО ЗА РІЗНИХ СПОСОБІВ ОСНОВНОГО ОБРОБІТКУ ҐРУНТУ ТА УДОБРЕННЯ

The article presents the results of experimental studies on the influence of different methods and depths of primary tillage, as well as nitrogen fertilizer rates, on the nutrient regime and weed infestation of grain sorghum crops. The research aims to scientifically substantiate and improve existing technological methods to increase the yield of grain sorghum plants, taking into account their morphobiological characteristics and reaction to the application of mineral fertilizers under various methods and depths of primary soil tillage. During the experiment, field, quantitative-weight, visual, laboratory, comparative-computational, and mathematical-statistical methods were used, employing widely recognized techniques and methodological recommendations. Results. The highest amounts of nitrates, mobile phosphorus compounds, and exchangeable potassium in the soil layer of 0-40 cm under grain sorghum crops during the years of the study were recorded against the background of the N60 nitrogen fertilizer dose applied during plowing to a depth of 28-30 cm. The lowest content of mobile phosphorus forms over the average of 3 years was observed in the disk tillage variant to a depth of 8-10 cm. The potassium content in the soil layer of 0-40 cm under grain sorghum crops over the average of 3 years of experimental research was characterized by a medium level. No significant difference was found in the utilization of available potassium by grain sorghum plants throughout the entire vegetation period, depending on the study factors. With an N30 dose, weed quantity increased by 1.4 and 2.2 times compared to the unfertilized background, depending on the soil tillage variant, and with an N60 dose, it increased by 1.3 and 2.1 times. The average yield of grain sorghum for plowing to a depth of 28-30 cm with the application of nitrogen fertilizers at a dose of N60 was 5.44 t/ha over the years of the study. For chisel tillage to the same depth, a yield of 3.89 t/ha was obtained, and for disk tillage, it was 2.54 t/ha. Conclusions. When growing grain sorghum in the conditions of the Southern Steppe of Ukraine, it is advisable to apply plowing to a depth of 28-30 cm against the background of nitrogen fertilizer application at a dose of N60, which creates favorable nutrient conditions and forms grain yield at the level of 5.44 t/ha. Keywords: grain sorghum, method and depth of tillage, nitrogen fertilizers, nutrient regime, weed infestation, yield.

Peculiarities in accummulation of radionuclides by fruit and berry trees and shrubs

The paper provides results of a long-term natural experiment with fruit and berry crops, grown in conditions of radioactive contamination at the territory of the former Semipalatinsk Test Site. The aim of the research is to study peculiarities in accumulation of artificial radionuclides by different species of trees and shrubs. The paper considers only one pathway of the radionuclide's intake, i.e. absorption of the elements by roots from soil. As the result quantitative parameters of 241Am, 137Cs, 90Sr, 239+240Pu transfer and distribution in different parts of the fruit and berry crops were found. At that radionuclides are not uniformly distributed in plants' organs and in most cases, it obeys the following regularity: leaves > branches > fruits. The difference in accumulation of 137Cs, 90Sr, 241Am and 239+240Pu for various organs can be range as follows 1.8–77, 1.6–750, 1.9–76 and 3–182 times respectively. The maximum concentrations of 137Cs in leaves of the researched plants more often were registered at the initial stages of vegetation period. Unlike 137Cs concentration of 241Am and 90Sr in leaves of the researched plants grows usually from the very beginning till the end of the entire vegetation period. The character of transuranium radionuclides accumulation during several years was determined for researched plants. Data obtained can become input parameters for models used to describe the behavior of radioactive substances and assess the risk of contaminated fruit and berry crops for territories having unfavorable radiological situation.

Development of flower meadows in an urbanized environment

Abstract With increasing urbanization, it is necessary to create green infrastructure in cities and urban areas to improve not only the quality of life for residents, but also the health and sustainability of local ecosystems. One effective way to create green spaces is by establishing meadows filled with diverse plant species. These meadows can provide numerous benefits, such as aiding pollinator conservation, improving air and water quality, and increasing biodiversity. Therefore, creating these meadows is an important component of urban ecology. Seven types of flower meadow mixtures from a Czech company were sown in 12 plots within the Hliník Urban Park in Nové Zámky, Slovak Republic. The development of the vegetation and the impact of maintenance management and climatic factors were monitored during the vegetation period of 2021‒2022, and the plots are still being monitored. The results of the flower meadow research in 2021 showed that improper maintenance and insufficient precipitation negatively influenced the vegetation’s development. Grasses were most prevalent during the summer months, while legumes were more common in the spring months. The analysis of the plots revealed that four out of 12 plots were dominated by annuals and grasses, which were the most abundant throughout the entire vegetation period. In 2022, it was observed that grasses were most prevalent in May, legumes in June and July, and annuals occurred sporadically in all plots. Insufficient precipitation and high temperatures in 2022 created unfavorable conditions for the thriving of the flower meadow vegetation, resulting in a high proportion of opportunistic species. Due to the impact of stress factors, the vegetation in the plots dried up.

MONARDA FISTULOSA L. FROM THE FOREST-STEPPE ZONE OF WESTERN SIBERIA: ANTI-INFLUENZA ACTIVITY OF PLANT COMPONENTS DURING THE VEGETATION PERIOD

This is a study on antiviral activity of various extracts from the plant Monarda fistulosa L. cultivated in the forest-steppe zone of Western Siberia during the vegetation period. The activity of aqueous and aqueous-ethanolic extracts of M. fistulosa during the whole vegetation period and two polyphenolic fractions from this plant at the flowering stage was investigated against human influenza virus A/Aichi/2/68 (H3N2) and avian influenza virus A/chicken/Kurgan/05/2005 (H5N1). The anti-influenza activity was compared among the extracts and the polyphenolic fractions from M. fistulosa at the flowering stage. It was shown that antiviral activity against each subtype of the influenza A virus differed throughout the entire vegetation period, depending on the developmental stage of M. fistulosa and the type of extraction. Influenza virus A/Aichi/2/68 (H3N2) infectivity was most strongly inhibited by aqueous-ethanolic extracts from M. fistulosa raw material collected at the growth stage and by the aqueous extract from the fruiting initiation stage. Inhibition of the infectivity of influenza virus A/chicken/Kurgan/05/2005 (H5N1) was achieved by one or another M. fistulosa extract almost throughout the whole vegetation period. It is found that Polyphenolic Fractions 1 and 2 are more active against influenza virus A/Aichi/2/68 (H3N2), but aqueous and aqueous-ethanolic extracts are more active against influenza virus A/chicken/Kurgan/05/2005 (H5N1). On the condition of further in-depth studies, our experimental data suggest that M. fistulosa plant components can be recommended as medicinal (antiviral) substances against influenza viruses A/Aichi/2/68 (H3N2) and A/chicken/Kurgan/05/2005 (H5N1).

MONARDA FISTULOSA L. FROM THE FOREST-STEPPE ZONE OF WESTERN SIBERIA: ANTI-INFLUENZA ACTIVITY OF PLANT COMPONENTS DURING THE VEGETATION PERIOD

This is a study on antiviral activity of various extracts from the plant Monarda fistulosa L. cultivated in the forest-steppe zone of Western Siberia during the vegetation period. The activity of aqueous and aqueous-ethanolic extracts of M. fistulosa during the whole vegetation period and two polyphenolic fractions from this plant at the flowering stage was investigated against human influenza virus A/Aichi/2/68 (H3N2) and avian influenza virus A/chicken/Kurgan/05/2005 (H5N1). The anti-influenza activity was compared among the extracts and the polyphenolic fractions from M. fistulosa at the flowering stage. It was shown that antiviral activity against each subtype of the influenza A virus differed throughout the entire vegetation period, depending on the developmental stage of M. fistulosa and the type of extraction. Influenza virus A/Aichi/2/68 (H3N2) infectivity was most strongly inhibited by aqueous-ethanolic extracts from M. fistulosa raw material collected at the growth stage and by the aqueous extract from the fruiting initiation stage. Inhibition of the infectivity of influenza virus A/chicken/Kurgan/05/2005 (H5N1) was achieved by one or another M. fistulosa extract almost throughout the whole vegetation period. It is found that Polyphenolic Fractions 1 and 2 are more active against influenza virus A/Aichi/2/68 (H3N2), but aqueous and aqueous-ethanolic extracts are more active against influenza virus A/chicken/Kurgan/05/2005 (H5N1). On the condition of further in-depth studies, our experimental data suggest that M. fistulosa plant components can be recommended as medicinal (antiviral) substances against influenza viruses A/Aichi/2/68 (H3N2) and A/chicken/Kurgan/05/2005 (H5N1).

The influence of weather and climate parameters on the winter rapeseed productivity

Purpose. To study the influence of hydrothermal resources on the productivity of winter rapeseed. Methods. Field (conducting phenological observations and records), measuring and weighting (for recording productivity and yield), mathematical, statistical and correlational analysis (objective assessment of the obtained experimental data). Results. Varieties of winter rapeseed of different ecological and geographical origin were taken as research material. For the analysis, the conditions of the full vegetation period, “seedlings-termination of vegetation”, “restoration of vegetation-beginning of ripening” and “flowering-beginning of ripening” were chosen as the most critical ones. The importance of using the hydrothermal coefficient as an integral indicator in determining the cumulative effect of climatic factors on the yield characteristics of winter rapeseed plants has been proven. It has been established that the following factors have the greatest influence on the formation of rapeseed productivity: duration of the growing season, the sum of active temperatures and the sum of precipitation under a above +10°C temperature regime, especially during the “flowering-beginning of ripening” period. Conclusions. Hydrothermal conditions affect the productivity of winter rapeseed plants. During the entire vegetation period, the following factors had the greatest positive influence: the length of the vegetation period (in particular, when tfact >0o to +5oC and >+10oC), the sum of temperatures tfact >0o to +5oC, the amount of precipitation. From the beginning of germination to the entry into a state of rest and after the resumption of vegetation in the spring, the following factors have the strongest effect on plants: duration of the vegetation period at tfact >0o to +5oC and >+10oC, the availability of moisture at temperatures from 0o to +10oC. During the flowering-ripening period, the length of the growing season had a positive effect, in particular at air temperature >+10°C against the background of a fairly high sum of active temperatures. The yield of winter rapeseed depends on many abiotic factors, which always provide optimal conditions for the sufficient plant development in autumn and spring, but can negatively affect the flowering of plants, and, accordingly, reduce their productivity.

The results of the application of growth-stimulating preparations of a new generation in the cultivation of a number of green cabbage varieties

Field studies on the cultivation of green cabbage varieties and hybrids using various growth stimulants against the background N120P60K60 were carried out on an irrigated area located at a distance of 1.5 km northwest of the village Solenoe Zaimishche (Astrakhan region) on an irrigated land use area of FSBNU "Pre-Caspian Agrarian Federal Scientific Center of the Russian Academy of Sciences." As a result of the obtained study, the positive effect of leaf treatments during the entire vegetation period was established. Especially the best effect was after joint application of Novosil + N120P60K60 in the hybrid Aggressor F1. At the same time, the yield was 57.5 tons/ha with an increase to the control variant of 15.7 tons/ha.

Influence of agroclimatic conditions of the spring-summer vegetation on the formation of winter wheat yield under the needs of the forest-steppe of Western Siberia

Air temperature and moisture availability are the main environmental factors that have a significant impact on the development of plants during the growing season. The aim of this study is to study the relationship of yield and its constituent elements with climatic factors and to show their role in the formation of productivity of winter wheat. The research was carried out in 2009-2022 in the fields of the Siberian Research Institute of Plant Growing and Breeding, a branch of the Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences. The research material was varieties and breeding lines of winter soft wheat of competitive variety testing. A positive dependence of the amount of precipitation and the hydrothermal coefficient in the interphase period “resumption of vegetation - trumpeting” with the duration of the growing season (r = 0.78; r = 0.73), productive tillering (r = 0.59; r = 0.64) was revealed, plant height (r = 0.60; r = 0.58), number of grains per plant (r = 0.66; r = 0.67). The correlation coefficient of productivity with the HTC and the amount of precipitation was r = 0.66 and r = 0.67, respectively, in the period of “booting - earing”. There is a significant negative correlation of resistance to lodging with both HTC and precipitation (r = -0.63; r = -0.56). The correlation coefficient of the HTC and the amount of rainfall with resistance to lodging in the interphase period “heading - wax ripeness” was significant (r = 0.55). HTC in the period “heading - wax ripeness” was directly proportional to the grain size index r = 0.60 and the amount of precipitation with a mass of 1000 grains r = 0.58. For the entire period of spring-summer vegetation, the correlation coefficient of the HTC and the amount of rainfall with the duration of the growing season was r = 0.63 and r = 0.65, respectively, with a height of r = 0.71 and r = 0.72, resistance to lodging r = -0.68 and r = -0.64 and overall bakery score r = -0.62 and r = -0.63. The amount of precipitation throughout the entire spring-summer vegetation has a positive effect on the grain weight per plant (r = 0.57). The sum of effective temperatures has a positive relationship with the nature of the grain in the period of “booting - heading” (r = 0.65). The correlation coefficient of the sum of effective temperatures with the amount of gluten in the period “heading - wax ripeness” r = 0.74 for the entire spring-summer vegetation r = 0.67.

Rain-fed agriculture in the steppe and forest-steppe zone of the Ural River basin and the adaptation of agricultural technologies to changing moisture availability as a way to preserve surface water resources

Aim. The aim of the research was to determine the relationship of winter wheat grain yields with meteorological parameters, the determination of the dynamics and current level and the selection and scientific justification of adaptive agricultural technologies.Material and Methods. Retrospective analysis was undertaken of meteorological conditions and gross winter wheat harvests by standard methods of correlation and regression analysis. The strength of the connection between the data of individual arrays was determined, as well as the identification of joint variation of productive and factorial features by pairwise comparison of their time series.Results. Six joint variations of time series of productive (gross grain harvest) and factorial features (hydrothermal conditions of vegetation periods and structural indicators of crops) with medium and high closeness of correlation, expressed in the form of multiple regression equations, were revealed.Conclusion. The results of the studies indicate a close direct relationship between gross grain harvest and yield from the harvesting area (r = 0.79), which in turn is inversely dependent (to an average degree) on the sum of the active air temperatures of the entire period from sowing to harvesting (r = 0.64). Из осадков различных периодов вегетации преимущественное прямое влияние на урожайность зерна оказывают осадки холодного периода года (r = 0.49) и всего активного периода вегетации от начала парования до уборки (r = 0.39). Of the precipitation of different periods of vegetation, the predominant direct effect on grain yield is exerted by precipitation during the cold period of the year (r = 0.49) and the entire active period of vegetation from the beginning of fallow to harvest (r = 0.39). The effect of amounts of precipitation for certain short periods of vegetation is much lower. Under current conditions, the stability of winter wheat grain production will be determined by the adaptability of agricultural technologies to the increasing aridity of the climate, which significantly worsens the moisture supply of plants.

Assessment of NDVI Dynamics of Maize (Zea mays L.) and Its Relation to Grain Yield in a Polyfactorial Experiment Based on Remote Sensing

Remote sensing is an efficient tool to detect vegetation heterogeneity and dynamics of crop development in real-time. In this study, the performance of three maize hybrids (Fornad FAO-420, Merida FAO-380, and Corasano FAO-490-510) was monitored as a function of nitrogen dose (0, 80 and 160 kg N ha−1), soil tillage technologies (winter ploughing, strip-tillage, and ripping), and irrigation (rainfed and 3 × 25 mm) in a warm temperature dry region of East-Central Europe. Dynamics of the Normalized Difference Vegetation Index (NDVI) were followed in the vegetation period of 2021, a year of drought, by using sensors mounted on an unmanned aerial vehicle. N-fertilization resulted in significantly higher NDVI throughout the entire vegetation period (p < 0.001) in each experimental combination. A significant positive effect of irrigation was observed on the NDVI during the drought period (77–141 days after sowing). For both the tillage technologies and hybrids, NDVI was found to be significantly different between treatments, but showing different dynamics. Grain yield was in strong positive correlation with the NDVI between the late vegetative and the early generative stages (r = 0.80–0.84). The findings suggest that the NDVI dynamics is an adequate indicator for evaluating the impact of different treatments on plant development and yield prediction.

Temporal Dynamics of CO2 Fluxes Measured with Eddy Covariance System in Maize, Winter Oilseed Rape and Winter Wheat Fields

The full understanding of variation and temporal changes in carbon dioxide (CO2) fluxes in cropland may contribute to a reduction in CO2 emissions from agriculture. The aim of this study was to determine the CO2 exchange intensity in the three most popular crops in Poland. The CO2 fluxes in summer maize, winter oilseed rape and winter wheat fields were measured using the eddy covariance system. The seasonal dynamics of CO2 fluxes for all studied crops varied from each other due to individual dynamics in atmospheric CO2 assimilation of each species through the growing season. The weighted average values of CO2 fluxes calculated for the entire vegetation period were −22.22 µmol CO2 m−2 s−1, −14.27 µmol CO2 m−2 s−1 and −11.95 µmol CO2 m−2 s−1 for maize, oilseed rape and wheat, respectively. All the studied agro-ecosystems were carbon sinks during the growing season. The highest negative values of CO2 fluxes (−36.31 µmol CO2 m−2 s−1 and −33.56 µmol CO2 m−2 s−1) were observed in the maize field due to the high production of biomass. However, the maize field was also the most significant carbon source due to slow growth of plants at the beginning of the growing season, and due to leaving the field fallow after harvest until the next sowing. In these two periods, the CO2 fluxes ranged from 0.59 µmol CO2 m−2 s−1 to 3.72 µmol CO2 m−2 s−1. CO2 exchange over wheat and oilseed rape fields was less intense, but more even throughout the growing season. In the wheat field, the CO2 fluxes ranged from −1.70 µmol CO2 m−2 s−1 to −23.49 µmol CO2 m−2 s−1 and in the oilseed rape field they ranged from −1.40 µmol CO2 m−2 s−1 to −22.08 µmol CO2 m−2 s−1. In addition, the catch crop in the oilseed rape field contributed to the intensive absorption of CO2 after harvesting the main crop.

Assessment of physicochemical characteristics of biofertilizers and their role in the rooting capacity of plants

The concentration of supplied mineral nutrients is one of the most important and limiting factors for enhancing the efficiency of plant nutrition. Optimal concentration of nutrient solutions (NS) provide plants with the necessary amount of nutrients. From this point of view, research on several physicochemical parameters that characterize concentrations of NS and uptake of nutrients by the plants remains an actual problem. The changes of electrical conductivity (EC) and total dissolved solids (TDS) depending on the concentration of biofertilizer as well as the role of biofertilizer solutions on the rooting capacity of cuttings (lateral sprouts) of Callisia fragrans are presented here. The EC and TDS of the biofertilizer-water mixture changed gradually according to the biofertilizer concentration. The biofertilizer solution was a good medium for the rooting of C. fragrans cuttings. The results could help to provide the crops with the necessary amount of mineral nutrients and regulate the suitability of irrigation during the entire vegetation period.

Microelement composition of spring rape plants depending on the specified experimental conditions

The aim of the study was to study the effect of various doses of chicken manure (CP), zeolite (C), their mixtures and mineral fertilizers on the accumulation of microelements in the vegetative organs of spring rape plants at different stages of development. The results of the experiment showed that the introduction of the zeolite-containing rock of the Terbunskoye deposit promoted a decrease in such trace elements as Cu, Zn and Mn in the vegetative mass of rapeseed throughout the entire period of plant development. On experimental plots using organic-mineral mixtures (CP 2.5 t / ha + C 3 t / ha, CP 5 t / ha + C 3 t / ha, CP 10 t / ha + C 3 t / ha) the active adsorption of the zeolite-containing rock of the Terbunskoye deposit in relation to Zn was revealed, which contributed to a decrease in the element in the vegetative mass of rape in the variants of the experiment throughout the entire vegetation period of plants. Consequently, the studies carried out make it possible to recommend the cultivation of spring rapeseed using organic waste as fertilizers together with natural zeolite in the forest-steppe conditions CHR.

FEATURES OF THE MANIFESTATION OF CALENDULA OFFICINALIS POWDERY MILDEW

Calendula officinalis are an annual light-loving, moisture-loving herbaceous plant, the inflorescences of which are raw materials for the pharmaceutical, food, and perfumery and cosmetic industries. The species composition of pathogens, their features of manifestation and development on medicinal plants are insufficiently studied. Powdery mildew is one of the most common and dangerous diseases of medicinal plants. The appearance of powdery mildew usually coincides with the flowering phase of medicinal plants (the month of June). With strong development, the causative agent of the disease leads to the drying of leaves and stems and the death of plants. Diseased plants lag behind in growth, generative organs recover later after three collections of raw materials. During the research period (2019-2021), the prevalence and development of powdery mildew of medicinal plants was monitored, its harmfulness and development features were determined, and the resistance of various varieties was assessed. When accounting for powdery mildew, the following indicators were evaluated: the number of affected plants - in percent; degree of damage - in points visually. Generally accepted methods in medicinal plant breeding were used for the research. The total size of the plots is 20-25 m2, accounting 20-30 m2, with four repetitions. The field evaluation of the resistance of varieties of medicinal plants for resistance to diseases was carried out on a natural infectious background during the period of maximum development of diseases (2-3 times during the entire vegetation period - June-August). High resistance to the powdery mildew pathogen during the research period was observed in the varieties Tangerine Twist, Dejavu, Indian Prince, Orange King, Silk Kiss, Dejavu, Indian Prince, Red Doctor Citrongelb, Red Buff and Sherbet. Cremebrule, Citron, Fiesta and Princess varieties had a weak susceptibility to the pathogen of powdery mildew. Varieties Monarch, Pink Surprise, Orange Heart, Magic Heart and Touch of Red were susceptible to powdery mildew.

The effect of crop rotation on the soil biological activity

The current paper has presented the results of long-term experiments on the study of the biological activity of sod-podzolic soil by the application method in field crop rotations. The experimental part of the work was carried out on the experimental plots of the Mari Research Institute of Agriculture, a branch of the FSBSI FARC of the North-East in 1996–2020. The trials were laid down in 1996 and 1998. The trial was laid down in two factors. Factor A included such types of crop rotations as grain-grasses crop rotations (oats + clover, clover of 1 year of use, winter crops, vetch-oat mixture for grain, spring wheat, barley as a control grain crop); the first rotation of crops (annual leguminous grasses, winter crops, barley, potatoes, vetch-oat mixture for grain, spring wheat); the second rotation of crops (vetch-oat mix[1]ture for grain, spring wheat, potatoes fertilized with manure (80 t/ha), barley + clover, clover of 1 year of use, winter crops); the third rotation of crops (barley + clover, clover of 1 year of use, clover of 2 years of use, winter crops, pota[1]toes, oats). Factor B included application of mineral fertilizers: control grain crop (without fertilizers); N60P60K60. There has been established that the activity of soil microflora mainly depended on the presence of organic matter in the soil. The largest activity of cellulose-destroying microorganisms against a natural background of fertility was identified in the second rotation of crops, with the introduction 23.9% of manure for potatoes in the first period (45 days) and 54.7% in the second period (90 days) of exposure. The slightest biological activity of the soil was identified in the grain-grasses crop rotation (with 83% of grain crops); it was 17.7% in the first 45 days and 43.4% in the second period of exposure. That was caused by the deficit of organic matter. The introduction of mineral fertilizers in a dose of N60P60K60 under pre-sowing tillage significantly increased the soil biological activity in comparison to the unfertilized background, and a fairly high intensity of flax decomposition was observed in the second rotation of crops with 24.9% in 45 days and 56.8% in 90 days. Correlation analysis (1998-2019) between the mean flax decomposition under crops for the entire vegetation period and the value of the hydrothermal coefficient (HThC) showed a close direct correlation, which in the first and second periods of exposure was 0.87–0.90 and 0.86–0.89, respectively.

Evaluation of RGB and Multispectral Unmanned Aerial Vehicle (UAV) Imagery for High-Throughput Phenotyping and Yield Prediction in Barley Breeding

With advances in plant genomics, plant phenotyping has become a new bottleneck in plant breeding and the need for reliable high-throughput plant phenotyping techniques has emerged. In the face of future climatic challenges, it does not seem appropriate to continue to solely select for grain yield and a few agronomically important traits. Therefore, new sensor-based high-throughput phenotyping has been increasingly used in plant breeding research, with the potential to provide non-destructive, objective and continuous plant characterization that reveals the formation of the final grain yield and provides insights into the physiology of the plant during the growth phase. In this context, we present the comparison of two sensor systems, Red-Green-Blue (RGB) and multispectral cameras, attached to unmanned aerial vehicles (UAV), and investigate their suitability for yield prediction using different modelling approaches in a segregating barley introgression population at three environments with weekly data collection during the entire vegetation period. In addition to vegetation indices, morphological traits such as canopy height, vegetation cover and growth dynamics traits were used for yield prediction. Repeatability analyses and genotype association studies of sensor-based traits were compared with reference values from ground-based phenotyping to test the use of conventional and new traits for barley breeding. The relative height estimation of the canopy by UAV achieved high precision (up to r = 0.93) and repeatability (up to R2 = 0.98). In addition, we found a great overlap of detected significant genotypes between the reference heights and sensor-based heights. The yield prediction accuracy of both sensor systems was at the same level and reached a maximum prediction accuracy of r2 = 0.82 with a continuous increase in precision throughout the entire vegetation period. Due to the lower costs and the consumer-friendly handling of image acquisition and processing, the RGB imagery seems to be more suitable for yield prediction in this study.

Winter wheat crop water consumption and its effect on yields in southern Romania, in the very dry 2019-2020 agricultural year

Researches on winter wheat in the south part of Romanian Plain during the dry years 2019 and 2020 have been focused on the crop water consumption issue in excessive conditions of air and soil drought. The wheat crop water consumption in the research sites (Calarasi and Teleorman counties), for the entire vegetation period, autumn – spring – summer, is between 1000 and 1050 m3 of water for each ton of wheat produced. Only in the spring-summer period, the wheat extracts a quantity of about 5960 m3 ha-1, i.e. 851 m3 t-1. The useful water reserve is normally located at about 1500 m3/ha-1, at a soil depth of 0-150 cm. In the spring of 2020, it has been below 400 m3 ha-1, so that at the beginning of May the soil moisture had almost reached the wilting coefficient (WC). Wheat plants have been able to survive the thermal and water shock of late spring - early summer, due to enhanced thermal alternation between air and soil. For a period of about 34 days, this alternation brought the plants 1-1.5 mm water, i.e. approximately 442 m3 ha-1, which allowed the prolongation of the plant’s agony until the rains of the second half of May. Yields have been, depending on the variety, between 1500 and 3000 kg ha-1, in average, covering only 60% of the crop costs. Other measures to save water in the soil have also been proposed in the paper.