Winter Rapeseed Research Articles

Estimation of the Leaf Area Index of Winter Rapeseed Based on Hyperspectral and Machine Learning

Leaf area index (LAI) is essential for evaluating crop growth and development. Destructive manual measurement methods mainly achieve traditional crop LAI acquisition. Due to the advantages of being fast and non-destructive, spectroscopy technology provides a feasible method for obtaining crop LAI. In order to achieve efficient acquisition of winter oilseed rape LAI, this study collected hyperspectral data and LAI data at the full-bloom stage of winter oilseed rape. It calculated the spectral indexes related to the LAI of the original spectrum and the first-order differential spectrum, respectively. The index with the highest correlation with the LAI of winter oilseed rape at the flowering stage was selected as the optimal spectral index for input. Subsequently, three machine learning methods, Back Propagation Neural Network (BPNN), Support Vector Machine (SVM), and Random Forest (RF), were used to construct the LAI model of winter oilseed rape, and the model was tested. The results show that the correlation coefficient between the spectral index calculated by the first-order differential processing of the original spectral data and the LAI of winter rapeseed is significantly improved compared with the original data. Among them, the spectral index NDVI with the best correlation coefficient with LAI can be obtained under the first-order differential: the correlation coefficient is 0.734, and the wavelength combination is 716 nm and 724 nm. At the same time, we found that when the input variables are the same, the RF model has higher estimation accuracy than the other models. The best estimation accuracy is obtained when the input variable is the first-order differential spectral index. The R2 of the model validation set is 0.810, RMSE is 0.455 cm2/cm2, MRE is 10.465%, and the model accuracy is high. The results of this study can provide a theoretical basis for crop monitoring based on spectral technology and provide a theoretical basis for crop growth.

Genome-Wide Identification of GSTs Gene Family and Functional Analysis of BraGSTF2 of Winter Rapeseed (Brassica rapa L.) under Cold Stress.

The largest gene families in plants were found to be Glutathione transferases (GSTs), which played significant roles in regulating plant growth, development, and stress response. Within the GSTs gene family, members were found to play a crucial role in the low-temperature response process of plants. A comprehensive study identified a total of 70 BraGSTs genes. Cluster analysis results demonstrated that the BraGSTs in Brassica rapa (B. rapa) could be categorized into eight sub-families and were unevenly distributed across ten chromosomes. The 39 BraGSTs genes were found to be organized into 15 tandem gene clusters, with the promoters containing multiple cis-elements associated with low-temperature response. Cold stress was observed to stimulate the expression of 15 genes, with the BraGSTF2 gene exhibiting the highest level of expression, suggesting its significant involvement in winter B. rapa's response to low-temperature stress. Subcellular localization analysis of the BraGSTF2 protein indicated its potential expression in both the cell membrane and nucleus. The analysis of stress resistance in BraGSTF2 transgenic Arabidopsis thaliana lines demonstrated that the over-expression of this gene resulted in significantly elevated levels of SOD, POD activity, and SP content compared to the wild type following exposure to low temperatures. These levels reached their peak after 24 h of treatment. Conversely, the MDA content was lower in the transgenic plants compared to the wild-type (WT) Arabidopsis (Arabidopsis thaliana L.). Additionally, the survival rate of BraGSTF2 transgenic Arabidopsis was higher than that of the WT Arabidopsis thaliana, suggesting that the BraGSTF2 gene may play a crucial role in enhancing the cold stress tolerance of winter B. rapa. This study lays a foundation for further research on the role of the BraGSTs gene in the molecular regulation of cold resistance in winter B. rapa.

Prediction of Seedling Oilseed Rape Crop Phenotype by Drone-Derived Multimodal Data

In recent years, unmanned aerial vehicle (UAV) remote sensing systems have advanced rapidly, enabling the effective assessment of crop growth through the processing and integration of multimodal data from diverse sensors mounted on UAVs. UAV-derived multimodal data encompass both multi-source remote sensing data and multi-source non-remote sensing data. This study employs Image Guided Filtering Fusion (GFF) to obtain high-resolution multispectral images (HR-MSs) and selects three vegetation indices (VIs) based on correlation analysis and feature reduction in HR-MS for multi-source sensing data. As a supplement to remote sensing data, multi-source non-remote sensing data incorporate two meteorological conditions: temperature and precipitation. This research aims to establish remote sensing quantitative monitoring models for four crucial growth-physiological indicators during rapeseed (Brassica napus L.) seedling stages, namely, leaf area index (LAI), above ground biomass (AGB), leaf nitrogen content (LNC), and chlorophyll content (SPAD). To validate the monitoring effectiveness of multimodal data, the study constructs four model frameworks based on multimodal data input and employs Support Vector Regression (SVR), Partial Least Squares (PLS), Backpropagation Neural Network (BPNN), and Nonlinear Model Regression (NMR) machine learning models to create winter rapeseed quantitative monitoring models. The findings reveal that the model framework, which integrates multi-source remote sensing data and non-remote sensing data, exhibits the highest average precision (R2 = 0.7454), which is 28%, 14.6%, and 3.7% higher than that of the other three model frameworks, enhancing the model’s robustness by incorporating meteorological data. Furthermore, SVR consistently performs well across various multimodal model frameworks, effectively evaluating the vigor of rapeseed seedlings and providing a valuable reference for rapid, non-destructive monitoring of winter rapeseed.

The effectiveness of various doses of magnesium-containing fertilizers in the cultivation of winter rapeseed

The effect of various doses and forms of magnesium-containing fertilizers on the production process of winter rapeseed plants was studied in field experiments. It was found that the combined use of Agromag magnesium-containing fertilizers contributed to an increase in the yield of winter rapeseed plants. An increase in the dose of magnesium-containing fertilizers did not lead to an increase in the efficiency of applied fertilizers. The use of magnesium-containing fertilizers containing sulfur has led to an increase in the efficiency of fertilizers due to an increase in the mass of seeds per 1 plant.

Comprehensive Evaluation of the Efficient and Safe Utilization of Two Varieties of Winter Rapeseed Grown on Cadmium- and Lead-Contaminated Farmland under Atmospheric Deposition

To determine the feasibility of planting rapeseed to safely utilize heavy metals (HMs)-contaminated farmlands surrounding working smelters under atmospheric deposition, a field trial was conducted to analyze the yields, cadmium (Cd) and lead (Pb) concentrations, health risks, and economic benefits of 15 rapeseed cultivars (13 Brassica napus L. and two Brassica campestris L.) in Jiyuan City, Henan Province, China. The results show that the seeds’ Cd concentration was 0.12–0.64 mg·kg−1 and the seeds’ Pb concentration was higher than Cd at 0.49–1.22 mg·kg−1. The Cd bioconcentration factor of B. campestris (0.702–0.822) was higher than that of B. napus (0.246–0.502). Additionally, Cd and Pb transfer factors from the stems to the pods and seeds were 0.34–1.20 and 0.54–4.53, respectively. Combined with a comprehensive analysis of the annual deposition data of Cd and Pb, 16.40 and 345.79 kg·hm−2, respectively, HMs in the seeds were not only derived from those in the soil, but were also derived from the atmosphere. Furthermore, the Cd and Pb levels in rapeseed oil, meal, and straw met the requirements stipulated in the standards for food safety, feeds hygiene, and organic fertilizer in China. Rapeseed–maize rotation yielded a profit of 15,550 CNY·a−1·hm−2, thereby increasing the economic output by 133.8%. A cluster analysis revealed that B. campestris SYH and ZS100 and B. napus ZY-821 showed the greatest comprehensive benefits. In conclusion, rapeseed cultivation is a viable and extendable approach that can achieve the safe utilization of typical HMs-contaminated farmland caused by atmospheric deposition in Northern China.

Analysis and Prediction of the Impact of Socio-Economic and Meteorological Factors on Rapeseed Yield Based on Machine Learning

Rapeseed is one of China’s major oil crops, and accurate yield forecasting is crucial to the growth of the rapeseed industry and the country’s food security. In this study, the data on natural and socio-economic factors from 2001 to 2020 and the yield of rapeseed in China were used as the data basis. The Pearson correlation coefficient was used to analyze the relationship between the influencing factors and the yield of rapeseed, and the prediction effect of four machine learning models (linear regression (LR), decision tree (DTR), random forest (RF), and support vector machine (SVM)) on the yield of rapeseed was compared in China’s main rapeseed-producing area. The results demonstrate that the yield of rapeseed in China showed an increasing trend, but fluctuated greatly. Rural electricity consumption, gross agricultural production, the net amount of agricultural fertilizer application, effective irrigation area, total power of agricultural machinery, and consumption of agricultural plastic film had a positive effect on the increase in rapeseed yield. However, due to the impact of climate change and disasters, the yield of rapeseed has had significant fluctuations. A Pearson correlation analysis showed that socio-economic factors (rural electricity consumption, gross agricultural production, effective irrigation area, total power of agricultural machinery, consumption of agricultural plastic film, etc.) played a dominant role in rapeseed yield changes. The RF model had a good prediction effect on rapeseed yield, and natural factors and socio-economic factors had different effects on spring rapeseed and winter rapeseed. Winter rapeseed yield was mainly affected by socio-economic factors, accounting for as high as 89% of the importance. Among them, the sown area of rapeseed and the effective irrigation area had the greatest impact. The effects of natural factors and socio-economic factors on spring rapeseed yield were similar, accounting for 47% and 53%, respectively, and the mean annual precipitation, sunshine duration, and sown area of rapeseed were the most influential variables.

Manure application followed by biochar application increases plant production regardless of soil dehydrogenase activity

AbstractBiochar is obtained by the pyrolysis of biomass, and contains abundant carbon and minerals. Biochar supplementation of soils can greatly improve soil health and quality, but these beneficial effects typically develop slowly over time. Depending on the quality of the biochar and the soil to which it is applied, it may take years before positive effects are apparent. This is because organic substances are slowly sorbed onto the biochar over time, and the biochar eventually becomes part of the sorption complex of the soil. It is therefore advisable to apply biochar together with some organic material. We examined the effect of co‐application of different doses of biochar with manure on soil dehydrogenase activity (DHA), soil oxidizable carbon (COX), cumulative soil respiration, soil buffering capacity, the soil exchange reaction (pH/KCl) and the production yield of winter rape seeds. We also determined seed production when artificial granular fertilizers were added to biochar and manure. The results showed that the application of biochar and manure significantly increased grain yield, DHA, the soil exchange reaction and cumulative respiration. Thus, application of biochar with organic material can increase seed yield and some properties of agricultural soils. However, the positive effect of biochar on seed yield was not directly proportional to biochar dose, in that the seed yield was lower for a biochar dose of 45 t/ha than 30 t/ha.

Responses of differentially expressed proteins and endogenous hormones in winter rapeseed (Brassica rapa L.) roots under water deficit stress

AbstractWinter rapeseed (Brassica rapa L.) can well‐adapt to environmental conditions such as barrenness, water deficit and low temperature in arid and semi‐arid planting regions and is the preferred rapeseed type. In this study, we analysed changes of root system morphology, antioxidant enzyme activity, endogenous hormone contents and differentially expressed proteins (DEPs) under control (CK), slight water deficit (SWD, 50–55% of maximum field water capacity), moderate water deficit (MWD, 40–45% of maximum field water capacity) and high water deficit (HWD, 30–35% of maximum field water capacity) conditions. Winter rapeseed experienced taproot elongation, decreased taproot diameter and increased lateral root number, under water deficit stress. The accumulation of reactive oxygen species (ROS) can cause membrane system peroxidation, and antioxidant enzyme activity increases to remove ROS. Changes in jasmonic acid (JA), salicylic acid (SA), cytokinin (CTK), auxin (IAA) and gibberellin (GA) levels promote the absorption of water and minerals by driving changes in the root system architecture to resist water deficit stress. A proteomic analysis has shown that DEPs are involved in energy metabolism, antioxidation response, osmotic regulation, hormone signal transduction, protein metabolism and the stress response, and these proteins are located in the peroxisome, chloroplast, mitochondrion, cell wall, vacuole, cytoplasm, extracellular space and cell membrane. In this study, multiple DEPs (malate dehydrogenase cytoplasmic 1 OS, 14‐3‐3‐like protein GF14 Psi, GA 3‐beta‐dioxygenase, glutathione reductase and jasmonate‐inducible protein) were involved in the root system architecture, revealing the complexity of the root response to water deficit. Significant/extremely significant synergistic relationships were observed between antioxidant enzyme activity and endogenous hormone contents. In conclusion, ROS, endogenous hormones and stress‐related proteins work synergistically to control the root system architecture of winter rapeseed roots in response to water deficit stress.

Определение содержания масла и основных жирных кислот семян рапса озимого с помощью ИК-спекрометрии

Near-infrared spectroscopy (NIRS) was used to estimate biochemical traits in winter rapeseed seeds. The purpose of the research was to develop graduating models for an IR-analyzer MATRIX-I to determine oil content and contents of oleic, linoleic, and linolenic fatty acids in oil in seeds. The research was conducted in the biochemistry laboratory of V.S. Pustovoit All-Russian Research Institute of Oil Crops, Krasnodar. An object of the research was the seeds of winter rapeseed cultivated in 2015–2022 in the central zone of the Krasnodar region. Oil content was determined on a NMR-analyzer AMV 1006М (Russia). Contents of oleic, linoleic, and linolenic fatty acids in oil were calculated by a chromatographic method on a gas chromatograph “Chromatek-Kristall 5000” on a capillary column SolGelWax 30 m × 0.25 mm × 1.0 µM with automatic dripper of liquid samples DAZh2M. We obtained the best results on quality of the graduating models (root mean square error of prediction, R determination, and a meaning of a residual deviation of prediction for a rank reflected on a diagram) on determination of oil content (RMSEP = 0.36%, R2 = 98.0, and RPD = 7.0); contents of oleic (RMSEP = 0.70%, R2 = 98.6, and RPD = 8.4), linoleic (RMSEP = 0.74%, R2 = 97.3, and RPD = 6.1), and linolenic (RMSEP = 0.28%, R2 = 97.2, and RPD = 6.0) fatty acids. The methodic “Rapeseed 51” for mass studying based on the developed graduating models for determination of oil content, contents of oleic, linoleic, and linolenic fatty acids in oil in unbroken seeds of winter rapeseed for IR-spectrometry in a middle sample (9–20 g) in cuvette with diameter 51 mm was obtained in a program OPUS LAB. This method allows conducting express-estimation of more than 100 samples of winter rapeseed seeds per an operating shift.

Жизнеспособность и оплодотворяющая способность пыльцы различного срока хранения у линий-восстановителей фертильности рапса озимого в тепличных условиях

To fasten breeding process of winter rapeseed hybrids, in V.S. Pustovoit All-Russian Research Institute of Oil Crops, a phytotron-greenhouse complex is used to obtain additional generations of plants. We studied the viability and fertilizing ability of pollen of nine lines-restorers of fertility and four maternal CMS-lines with purpose to determine optimal conditions for the hybridization in a greenhouse, which provide maximal amount of seeds. It was stated pollen of only open flowers of lines-restorers of fertility possesses the high viability – about 80–98%. When storing in a darkness at a room air temperature of 22–24 °C during 24 hour, pollen loses the viability by 2.0–2.5 times depending on a genotype. However, such important lowering of the pollen viability does not influence significantly on setting of seeds and seedpods. The seed formation in hybrids obtained after crossing with paternal lines having the viability of a day pollen from 15 to 52% did not distinguished significantly. The acceptable level of seed formation in hybrids was observed when using pollen with a storage period until five days. When using pollen storing for ten days at a temperature of 22–24 °C, seeds were not formed at hybrid combinations. There were detected the significant differences by the fertilizing ability between studied lines-restorers of fertility. So it is necessary to pay attention to this trait when developing commercial hybrids. The lowered fertilizing ability of pollen of the concrete restorer of fertility will influence the yield of hybrid seeds on the hybridization plots.

Наследование признака высокого содержания олеиновой кислоты в масле семян F2 и поколения BC1 рапса озимого (Brassica napus L.)

The aim of the work was to study the patterns of inheritance of the trait of high oleic content in the F2 and generation BC1 of winter rapeseed in order to obtain new knowledge about the genetic mechanisms of the high oleic acid contents in seed oil and scientifically based approaches to the development of the breeding germplasm with a high content of oleic acid. The studies were carried out in 2021– 2022 in the field. The material was reciprocal F1 hybrids from crossings of the high-oleic line VN-1848 (79.3%) and two lines from the cultivars Sarmat and Selegor of VNIIMK breeding with the traditional content of oleic acid in seed oil – 62.1 and 60.5%, respectively. Hybrids F1 were used to produce BC1 seeds. F2 and BC1 generations were obtained in 2022. In F2 hybrids, splitting into two phenotypic classes was observed in a ratio of 15 : 1. The first one included lines with oleic acid content in seed oil less than 79%, the second one – lines with high rates of this trait at the level or higher than the parental high-oleic component (18 : 1 > 79%). This proposes the control of a trait by two pairs of non-allelic genes with an additive effect. As a result of backcrosses using the high-oleic lines VN-1848 as the maternal component, 55 genotypes with a low content of oleic acid (18 : 1 < 79%) and 11 genotypes with high levels of this trait (18 : 1 > 79%) were obtained. This corresponded to a splitting ratio of 3 : 1. All χ2 values turned out to be less than 3.8, p > 0.05.The results of the studies confirm our assumption that the oleic acid content in seed oil is controlled by two pairs of non-allelic genes; the manifestation of this trait in plants is observed only when all alleles are in a homozygous recessive state.

Influence of weather conditions on wintering of winter rape depending on intensification factors

Purpose and objectives of the study. The aim of the study was to investigate the peculiarities of wintering of winter rape depending on the factors of intensification in the Right-Bank Forest-Steppe of Ukraine. Methods. General scientific and special research methods were used in the course of the work. Results. Weather conditions have made their adjustments over the years of research, especially significant impact on wintering of winter rape had the amount of precipitation over the years of research and varied greatly. Pre-sowing treatment and foliar fertilization of plants were of great importance, these measures had a positive effect on the studied aspects. It also contributed to the accumulation of high sugar content in the root collar of plants, the formation of a greater accumulation of absolutely dry plant mass, which accordingly provided a higher percentage of winter hardiness of winter rape plants by 8.0-10.3%. Analyzing the research, we indicate that the use of growth regulators in foliar feeding of winter rape plants against the background of pre-sowing seed treatment had a significant effect on the wintering of rape. Treatment of winter rape seeds with Vitavax 200 FF, 34 % w.c.c., before sowing, with growth regulator Vympel-K significantly increased field germination, and their joint use provided a more positive effect. Conclusions. The use of the growth regulator Vympel-K (500 g/t) indicated that the wintering of plants was better compared to the control (untreated seeds) and almost 5.8% higher than in the variants with seed treatment with Vitavax 200 FF, 34% w.c.k. (2.5 l/t). The use of the growth regulator Vympel foliarly in the fall in the rosette phase of 5-6 leaves against the background of pre-sowing seed treatment with Vitavax 200 FF, 34 % w.c. + growth regulator Vympel-K provided better growth and development of plants.

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.

Results of studies on the sealing of crop residues of leguminous crops with ploughshares

The article presents the results of experimental studies of the sealing of crop residues and their distribution over the depth of the cultivated soil layer by known general-purpose ploughshares without ploughshares. The research was carried out in fields with agrophones of winter wheat, chickpeas and winter rapeseed. The plowing of dark chestnut soils located in the steppe soil-climatic zone of the Left-Bank district of the Saratov region was carried out by aggregates K-701+PNL-8-40, K-701+PSK-8 and T-150K+PLN-5-35. As a result of field experiments, it was found out that straw, pollen and stubble are embedded in the soil in accordance with established agrotechnical requirements, more than 80%. Crop and plant residues are located in the bulk in the deep layers of the cultivated soil. Part of the stubble in an inclined position is located in the places where the layers of adjacent passages of the plow hulls meet. The design of the ploughshare-dump surface of the housing does not allow managing the upper organic-enriched soil layer.

Formation of winter rapeseed productivity in the Central Non- Chernozem region depending on seeding rates and the use of growth stimulants

Recently, rapeseed has become a popular crop in many countries of the world and the acreage is being expanded annually for its production. The demand for this crop is also explained by the fact that it is cultivated for oil seeds in many regions. Winter rapeseed seeds are in demand for feed purposes, because they produce high-quality presscake and meal for farm animals and poultry. The purpose of the research was to study the infl uence of diff erent seeding rates of winter rapeseed varieties Elvis, Loris and Sarmat and the use of growth stimulants Restart and Moddus to increase productivity, product quality and plant resistance to adverse environmental factors under the conditions of the Central Non–Chernozem region. The infl uence of optimized seed seeding rates, the use of modern growth stimulants on the productivity of adaptive varieties of winter rapeseed was determined, an optimized method of using growth stimulants on various varieties of winter rapeseed was used, which allows to improve plant growth and development, photosynthetic activity, and as a result to increase yields. The lowest prime-cost of gross production of Sarmat variety was formed in the variant with a seeding rate of 1,0 million seeds/ha when using the drug Moddus and was equal to 11,6 thousand rubles/ha or 2,6 thousand rubles/ha was less than Elvis variety and 0,9 thousand rubles/ha less than Loris variety. Thus, the expediency of reducing the seeding rates of winter rapeseed varieties Sarmat, Elvis and Loris from the recommended 2,0 to 1,0 million seeds/ha of germinating grains was confi rmed and the optimal use of growth stimulants in the cultivation of winter rapeseed was revealed.

Effects of a range of phosphorus levels on yield, phosphorus efficiency, and canopy sunlight interception in direct‐seeded winter rapeseed

AbstractPhosphorus (P) fertilization is a crucial practice for winter rapeseed (Brassica napus L.) production. With the shift to a direct seeding cropping system, the P fertilizer supply should be re‐evaluated for the requirement of direct‐seeded winter rapeseed in southwest China. A two‐factor field experiment was conducted in 2017–18 and 2018–19 in the region. The experiment aimed to investigate the responses of a wide range of P levels (0, 45, 90, 135, and 180 kg P ha−1) on yield, P‐efficiency, and canopy sunlight interception of direct‐seeded winter rapeseed. The results demonstrated that winter rapeseed yield was enhanced as the P fertilizer rate increased from 0 to 90 kg P ha−1, and excessive P fertilizer supply did not significantly contribute to higher grain yield at high P levels. Rapeseed produced 7.1–10.1 kg seed ha−1 to supply 1 kg P ha−1 average across different five P levels from 0 to 180 kg P ha−1. Phosphorus efficiency significantly firstly increased (0–90 kg P ha−1) and then progressively decreased with the rise of P levels (around 120 kg P ha−1). Greater P fertilizer rates were absorbed by the stem and pericarp while playing a negligible role in boosting winter rapeseed yield. When the target yield of 3000 kg ha−1 was set, the corresponding winter rapeseed canopy area index should be 1.42–2.71 to facilitate yield formation depending on the growth stages. Meanwhile, it intercepted 30.8%–88.7% of sunlight by the rapeseed canopy. A reduced P‐fertilizer level of 90–120 kg P ha−1 was recommended to obtain target yield with less environmental risks in direct‐seeded winter rapeseed planting regions.

Determination of winter rapeseed (Brassica napus L.) polymorphism based on SSR markers and morphological characters

The study presents the results of the genetic diversity estimation of winter rapeseed by molecular genetic analysis and the determination of polymorphism with morphological traits. The study aims to determine winter rapeseed hybrids polymorphism by SSR markers and the marker morphological characteristics. Twelve winter rapeseed hybrids which were examined within DUS testing and their 24 hereditary components were studied in 2021–2022. The study of rapeseed genotypes genetic diversity was carried out in 2021. It was determined that the majority of studied hybrids and their hereditary components by studied SSR markers are characterized with alleles of the same sizes and are homozygotic by these markers. Besides, it was found that the presence of only on one allele was identifed in hereditary components which was found in hybrids. This distribution allows to check the hybrid formula and to identify them. It was determined that the most polymorphic marker was Na12-A02, PIC is 0.77. The lowest value of PIC was obtained for Na12-E02 marker (0.47). On the average, for studied markers PIC is 0.66 which indicates the evenness of identifed alleles distribution by SSR markers among studied winter rapeseed genotypes. As results of cluster analysis, we obtained fve clusters of the studied hybrids by 8 SSR markers. The hybrids with genetic distances of 2.45 were the most similar hybrids. It was found that the hybrids with genetic distances of 5.83 and 5.74 were the most distinct. Three clusters were obtained as results of the cluster analysis based on morphological traits. It was determined that the most similar hybrids were the ones with genetic distances of 3.46. It was found that the most distinct hybrids had the genetic distances of 5.299.38. Thus, taking into account the various distribution of the studied genotypes by the SSR markers and morphological characteristics, SSR markers can be used as additional tool for the distinctness determination. Key words: genetic distances, winter rapeseed, allele frequencies, РІС, genetic diversity, SSR markers.

The effect of the method of preservation of bee honey on the development of the pharyngeal gland in honey bees Apis mellifera L

Modern agricultural systems involve the use of large monocultures, which significantly limits the variety of flowers for bees. The article presents data on the biochemical composition of monofloral bee pollen and its influence on the development of pharyngeal glands in honey bees. The conducted studies give reason to believe that the protein content in bee pollen depends on the species origin and the preservation method. The studied samples for protein content show that its amount ranges from 11.9 to 24.9 %. The maximum amount of protein was found in fresh rapeseed and apple bee pollen. To study the influence of monofloral diets on the growth and development of the pharyngeal gland, 9 groups of analogous bee families were formed, 3 in each, which were fed three types of feed. The first type is fresh bee pollen from the following plants: apple tree, dandelion, winter rapeseed, buckwheat, clover, chestnut, raspberry. The second type is a similar bee pollen, only after a year of deep freezing storage. The ration of the third species consisted of the indicated bee pollen only in the process of harvesting it was dried. Along with this, the formed group of bee families was divided into two more subgroups. Some consumed mixed feed in equal proportions, others did not have any protein feed. The duration of the experiment was 15 days. On the 10th day, the development of acini of the pharyngeal gland was determined. The morphometry of the acini and the dynamics of vesicle filling indicate that the best indicators were found in the group of bees that consumed mixed bee pollen. A highly beneficial increase in the length and width of the acini of the pharyngeal gland was revealed by 36.4 and 34.7 % compared to bees that did not consume pollen at all. A group of bees that received fresh rapeseed and apple seed in their diet fully demonstrated their potential for royal jelly production. The worst development of the pharyngeal gland was found in the group of bees that consumed dried dandelion nectar. In this group of bees, the area of the acini ranged from 15.5 to 16.4 thousand μm2. The relationship between the protein content in the diet and the degree of development of the pharyngeal gland was revealed. Of the researched methods of its preservation, the conditions of deep freezing turned out to be the best. The use of experimental monofloral diets has a negative effect on the internal indicators of the body of honey bees. Key words: Apis mellifera L., pharyngeal gland, nutrition, protein, bee pollen, pollen storage.

Agroecological assessment of short crop rotation on sod-podzolic soil

In the conditions of drained lands with unsatisfactory work of reclamation systems, in the Polissia zone it became possible to grow commercially attractive crops, in particular, such as winter rapeseed and corn for grain. A short-rotation crop rotation was analyzed: lupine — winter rapeseed — winter rye — corn, on the basis of which various variants of the fertilization system were studied, including by replacing litter manure with siderate and by-products of all crops in combination with the recommended for the zone and increased (intensive) mineral norms fertilizers. The goal of the task was to determine the optimal agrochemical support for grain crop rotation to obtain stable crop productivity and preserve soil fertility. It was noted that during the 2016–2020 research, during the growing season of agricultural crops, the reserves of productive moisture in the meter-long layer of drained sod-podzolic sandy soil decreased to 60–80 mm, that is, to a critical level. It was established that the overall productivity of the crop rotation depended on its saturation with corn, the grain yield of which was 6.01–7.13 t/ha on average over 5 years at different levels of organic and mineral nutrition. The highest yield of grain and fodder units from 1 ha of crop rotation area (4.23 and 4.52 tons, respectively) was obtained when by-products were applied together with an increased rate of mineral fertilizers (N67P84K91). It was established that the replacement of litter manure with the by-products of grain, leguminous and oilseed crops as an organic fertilizer, together with the use of the recommended (N45P56K61) and increased (N67P84K91) mineral fertilizer rates, does not reduce the productivity of crop rotation, ensures a deficit-free nitrogen balance and the annual accumulation of humus in the amount of 320 and 440 kg, respectively, which guarantees extended reproduction and increased soil fertility.

Assessment of the state and prospects of rapeseed production in Ukraine and in the world

The article analyses the statistical data of the United States Department of Agriculture on the main producers, exporters, importers and consumers of rapeseed, oil and meal and establishes that the EU, Canada and China are the leaders in terms of rapeseed production in the world. According to the forecasts, in 23/24 MY almost half of all imported seeds will be from the EU (5.1 mln tonnes) and China (3.0 mln tonnes). Canada is the world’s largest exporter of rapeseed and rapeseed products, and it is forecast that about 8.6 mln tonnes of the seeds will be sold to other countries, including the EU and China. Canada has been the largest exporter of rapeseed for many years. According to analysts’ forecasts, 8.6 mln tonnes of seeds, which is 48.6% of the total world exports, will be sold to other countries. Canada will export 3.1 mln tonnes of oil and 5.25 mln tonnes of rapeseed meal. In 23/24 MY, the EU countries are forecast to use 25.4 mln tonnes of rapeseed and its products for domestic consumption, while China — 18.4 mln tonnes. According to the State Statistics Service of Ukraine, in 2013, 0.95 mln ha of winter rapeseed were harvested, the gross harvest amounted to 2.28 mln tonnes, and the average yield was 2.40 t/ha. In 2022, the gross harvest of winter rapeseed was 3.25 million tonnes. At the same time, the harvested area was 1.13 mln ha, and the average yield in the country increased to 2.87 t/ha. Thus, over the past 10 years, the sown area in Ukraine has increased by 19%, and the gross seed harvest by 42.4%. The increase in sown areas, gross seed harvest and average yields was driven by improvements in certain elements of winter rape growing technology and the introduction of new varieties and hybrids. The State Register of Plant Varieties Suitable for Distribution in Ukraine includes 350 varieties and hybrids of winter rape. Over the past 10 years, 306 varieties and hybrids of winter rape have been included in the Register, which is 87.4% of the total. At the same time, 20 varieties and 6 hybrids of winter rape of Ukrainian breeding and 16 varieties and 264 hybrids of foreign breeding were registered.