Row Spacing Research Articles

Formation of biometric parameters of sowings of soybean variety ‘Sirelia’ on typical chernozems depending on the nutrition area

Purpose. To determine the effect of row width and seeding rate on the biometric parameters of sowings of the early-ripening soybean variety 'Sirelia'. Methods. The research was carried out in 2021–2023 in the stationary crop rotation of the Plant Breeding Department in the fields of the Agronomic Research Station of the National University of Life and Environmental Sciences of Ukraine (Pshenychne, Vasylkiv district, Kyiv region). Scheme of the experiment: factor A – sowing method: ordinary row with a row spacing of 19 cm; strip with a row spacing of 19 × 38 × 12 cm; wide-row with a row spacing of 38 cm; factor B – seeding rate: 450, 600 and 750 thousand seeds/ha. Recordings were carried out in the main phases of crop development: budding, flowering and grain filling. Results. The thickening of crops with an increase in the seeding rate from 450 to 750 thousand seeds/ha contributed to a significant increase in the height of soybean plants: by 3.5 cm for row spacings of 19 cm and by 5.9 cm for row spacing of 38 cm. Seeding rate of 450,000 seeds/ha led to a decrease in plant height by 4.1 cm, or 5.2%. Thus, from the given data it can be concluded that the height of soybean plants increased with an increase in the seeding rate. The influence of the sowing rate on the growth of plants at a row width of 38 cm was particularly significant. The absolute dry mass of plants in the budding phase was within the range of 2.87–4.00 g, in the flowering stage 4.81–6.93 g, and in the seed filling stage 11.6–21.5 g. During the last period, the mass of plants in the case of increasing the seeding rate from 450 to 750 thousand seeds/ha decreased by 8.9 g, for a row spacing of 19 cm, and for a row spacing 38 cm by 7.3 g. The highest mass of plants was for the row width of 38 cm and the sowing rate of 450,000 seeds/ha. Conclusions. The height of soybean plants increases with an increase in the seeding rate. This is explained by the fact that the thickening of crops causes shading and elongation of plants. Soybean plants were the highest (81.9 cm) at a row spacing of 38 cm and a seeding rate of 750,000 seeds/ha. The highest absolute dry weight of one soybean plant was formed at a seeding rate of 450,000 seeds/ha, and significantly decreases in case of its increase to 750 thousand seeds/ha for all methods of sowing. That is, the thickening of crops with an increase in the seeding rate from 450 to 750 thousand units/ha led to a significant decrease in the dry weight of plants, which is explained by the deterioration of the conditions for their growth and development, primarily due to high competition for life factors.

Photosynthetic activity of safflower under the effect of the elements of cultivation technology

Purpose. To establish the peculiarities of the formation of photosynthetic indicators of safflower varieties as affected by the elements of cultivation technology, specifically row width, row spacing, and sowing rate, in the Right Bank Forest Steppe of Ukraine. Methods. The research was carried out in 2021–2023 at the Agronomic Research Station of National University of Life and Environmental Sciences of Ukraine. The soil type was typical low-humus chernozem. The design of the field experiment provided for the study of the influence of the following factors: factor A – varieties: ‘Dobrynia’ and ‘Soniachnyi’; factor B – row width: 19, 38 and 57 cm; factor C – sowing rate: 100, 200 and 300 thousand seeds/ha. Results. The leaf area of safflower increased as the row width and sowing rate increased, which emphasizes the importance of optimizing the location of plants in the field for reaching effective photosynthesis and subsequent crop formation. In particular, at the time of flowering, in the ‘Dobrynia’ variety, the leaf area was 32.7, and in ‘Soniachnyi’ 31.2 thousand m2/ha; the varieties in general differed by 1.5 thousand m2/ha, which exceeded the value of the smallest significant differences by experience. At the same time, it was determined that the average leaf area for a row spacing of 19 cm was 30.7 thousand m2/ha. Increasing the row width to 38 cm contributed to the leaf area formation of 31.4 thousand m2/ha, which is 0.6 thousand m2/ha more than in the previous treatment. At a row spacing of 57 cm, the crops had a leaf area of 33.8 thousand m2/ha, which was 3.1 thousand m2/ha more than at a row spacing of 19 cm. Sowing rate of 100 seeds/ha resulted in leaf area of 31.0 thousand m2/ha, while sowing rates 200 and 300 thousand seeds/ha ensured a leaf area increase of 1.50 and 1.53 thousand m2/ha, respectively. In the budding stage, the highest content of the chlorophylls a and b in safflower plants was noted for row width of 38 cm and sowing rates of 200 and 300 thousand seeds/ha. The content of chlorophylls was 5.21 and 5.24 5.19 and 5.22 mg/g of dry matter, respectively, in ‘Dobrynia’, and 5.19 and 5.22 mg/g of dry matter in ‘Soniachnyi’. Conclusions. The highest parameters of the photosynthetic potential were obtained for row width of 57 cm and sowing rates of 200 and 300 thousand units/ha: in ‘Dobrynia’, 0.89–90 million m2 × day/ha in the period of budding – flowering, and 1.21–1.23 million m2 × day/ha in the period flowering – full maturity; in ‘Soniachnyi’ 0.93–0.94 million m2 × day/ha and 1.35–1.36 million m2 × day/ha, respectively. The parameters of net photosynthetic productivity (NPF) of crops in the period from flowering to full maturity in ‘Dobrynia’ was 1.59 g/m2 per day, and 1.47 g/m2 per day in ‘Soniachnyi’. At the same time, for a row width of 19 cm, the NPP was 1.73, and at 38 cm 1.76 g/m2 per day, and for a row spacing of 57 cm it was 1.11 g/m2 per day, which is 0.6 g/m2 per day less than for a row spacing of 19 cm. At the sowing rates of 100, 200 and 300 thousand seeds/ha, the NPP was, respectively, 1.29, 1.65, and 1.65 g/m2 per day. In ‘Soniachnyi’, the highest NPP indicators were obtained for a row spacing of 38 cm and a sowing rate of 300,000 plants/ha: 2.02 g/m2 per day; in ‘Soniachnyi’ for a row spacing of 19 and 38 cm and a seeding rate of 300,000 seeds/ha: 1.86 g/m2 per day for both options.

An image quality assessment method based on edge extraction and singular value for blurriness

The automatic assessment of perceived image quality is crucial in the field of image processing. To achieve this idea, we propose an image quality assessment (IQA) method for blurriness. The features of gradient and singular value were extracted in this method instead of the single feature in the traditional IQA algorithms. According to the insufficient size of existing public image quality assessment datasets to support deep learning, machine learning was introduced to fuse the features of multiple domains, and a new no-reference (NR) IQA method for blurriness denoted Feature fusion IQA(Ffu-IQA) was proposed. The Ffu-IQA uses a probabilistic model to estimate the probability of each edge detection blur in the image, and then uses machine learning to aggregate the probability information to obtain the edge quality score. After that uses the singular value obtained by singular value decomposition of the image matrix to calculate the singular value score. Finally, machine learning pooling is used to obtain the true quality score. Ffu-IQA achieves PLCC scores of 0.9570 and 0.9616 on CSIQ and TID2013, respectively, and SROCC scores of 0.9380 and 0.9531, which are better than most traditional image quality assessment methods for blurriness.

Growth and Productivity of Maize (Zea mays L.) as Influenced by Precision Nutrient Management and Intercropping Cowpea (Vigna unguiculata L.) under Hot and Sub-humid Region of Odisha

Background: Cereal-legume intercropping is an age-old practice in most of the countries. Among the major cereals, maize is a better choice to include in legume intercropping due to its morphology and wider row spacing. Therefore, legume intercropping in consort with proper nutrient management can enhance overall productivity of the system, further improving crop diversification, nutritional security and agriculture sustainability. Considering these aspects, the present study was performed to examine the growth and productivity of maize as influenced by precision nutrient management and cowpea intercropping. Methods: The present study was carried out during rabi season of 2022-23 at P. G. Research Farm of M.S. Swaminathan School of Agriculture, Odisha, India. The experiment was laid out in split-plot design with five intercropping combinations and five nutrient management treatments. All the treatments were replicated thrice. The plot size maintained was 5.0 m x 4.8 m. In case of maize and cowpea, high yielding hybrid ‘JKMH 4510’ and ‘KBC 9’ variety were taken for the study, respectively. Result: The results revealed that the growth parameters were significantly affected by intercropping ratios and nutrient management treatments. Although the yield attributes of maize were differed non significantly among the intercropping treatments but were significantly influenced by the nutrient treatments. In case of grain yield of maize, the Green Seeker-based nutrient management gave highest value with cowpea intercropping ratio of 1:1 and 2:2. LER and ATER were greater than unity, which indicated that the intercropping was advantageous. However, the maximum LER and Area Time Equivalent Ratio (ATER) were obtained from C3 (M+C 1:2) with 140:70:70 kg N, P2O5, K2O/ha, respectively. The study concluded that intercropping of maize + cowpea in 1:2 row ratio with Green Seeker-based nutrient management were advantageous over pure stand of maize fertilised with conventional nutrient management.

Effect of Organic and Inorganic Sources of Nutrients on Growth and Yield of Timely Sown Wheat (Triticum aestivum L.)

A comprehensive study examining the effects of organic and inorganic nutrient sources on the growth and yield of wheat was carried out during the Rabi season of 2020-21 at the Student's Instructional Farm, C.S. Azad University of Agriculture and Technology, Kanpur. The experimental design was a Randomized Block Design, with each treatment replicated three times across eight different treatments: Control (T1), 100% Recommended Dose of Fertilizers (RDF) (120:60:40 NPK kg/ha) (T2), RDF + Azotobacter (T3), RDF + Azotobacter + Farmyard Manure (FYM) @ 2.0 tons/ha + Phosphate Solubilizing Bacteria (PSB) @ 6.0 kg/ha + Trichoderma @ 5.0 kg/ha (T4), RDF + Vermicompost @ 2.5 tons/ha (T5), RDF + FYM @ 2.0 tons/ha + Vermicompost @ 1.0 ton/ha + Trichoderma @ 5.0 kg/ha (T6), RDF + FYM @ 2.0 tons/ha + Vermicompost @ 1.0 ton/ha + PSB @ 6.0 kg/ha + Azotobacter (T7), and RDF + FYM @ 2.0 tons/ha + Vermicompost @ 1.0 ton/ha + Azotobacter + PSB @ 6.0 kg/ha + Zinc @ 5.0 kg/ha + Sulphur @ 25 kg/ha (T8). The soil type was sandy loam with a pH of 8.13. The wheat variety Shekhar (K-1006) was planted on November 30, 2020, with a seed rate of 100 kg/ha and row spacing of 20 cm. The results indicated that the T8 treatment, which combined RDF, FYM, Vermicompost, Azotobacter, PSB, Zinc, and Sulphur, significantly improved plant growth characteristics such as height, fresh weight, dry weight, and number of tillers per plant, as well as yield-contributing factors including spike length, number of grains per spike, and test weight, compared to all other treatments. Specifically, the T8 treatment produced the highest grain yield, straw yield, and biological yield, recording 52.77, 67.55, and 120.32 quintals per hectare, respectively, which was significantly higher than the yields in treatments T1, T2, T3, and T4, and comparable to those in treatments T5, T6, and T7. Moreover, the T8 treatment achieved the highest gross income (Rs. 143,076.00), net income (Rs. 86,300.00), and benefit-cost ratio (2.52) when compared to all other treatments.

Low-altitude remote sensing-based global 3D path planning for precision navigation of agriculture vehicles - beyond crop row detection

Field path planning provides the basis for the autonomous navigation of agricultural vehicles. Existing path planning approaches are constrained to a 2D plane, disregarding the impact of terrain factors on navigation tasks. Furthermore, these methods generate non-global paths, as evidenced by their inability to accommodate the headland turning area while performing path planning based on the actual crop growth in the farmland. Low-altitude remote sensing technology, characterized by its high spatial resolution, timely data acquisition, and strong terrain perception, holds great potential for application in autonomous navigation. This study aims to integrate low-altitude remote sensing technology with path-planning tasks for agricultural vehicles by constructing oblique photography models of fields. The objective is to achieve global 3D path planning leveraging advanced methodologies rooted in deep learning and image processing. Four main steps were included in the proposed method. Low-altitude remote sensing models of field blocks were constructed first. Secondly, the models were converted to image patches for dataset establishment. Thirdly, primary crop row identification was conducted by semantic segmentation. Finally, global 3D paths covering the farmland and headland areas were generated. Tea fields in hilly areas were used to test the algorithm. Experiments revealed that the proposed method could be adapted to different field shapes, row numbers, row spacing, and vehicle turning radii. The proposed method uses deep learning and image processing as the primary technical tools but goes beyond traditional crop row detection to form a global path-planning strategy. In addition, the elevation information enabled by the 3D detection manner allows agricultural vehicles to gain a comprehensive understanding of both their own position and that of their destination. The dataset and the code are available at: https://github.com/ZeroHeading/Global-3D-path-generation.git.

Effect of Row Spacing on Brown Planthopper Incidence in Basmati Rice under Punjab Conditions

Effect of Row Spacing on Brown Planthopper Incidence in Basmati Rice under Punjab Conditions

Influence of High-Sugar Early and Mid-Late Genotypes on Yield and Quality of Sugarcane (Saccharum spp. Hybrid Complex) at Wider Row Spacing

A field experiment was conducted in Pusa during spring season of 2016-17, to evaluate 7 sugarcane genotypes (‘CoP 11436’, ‘CoP 11437’, ‘CoP 11438’, ‘CoSe 11451’, ‘BO 130’, ‘CoSe 95422’ and ‘BO 153’) in early maturing group and 7 sugarcane genotypes viz., ‘BO 155’, ‘CoSe 11453’, ‘CoSe 11454’, ‘CoSe 11455’, ‘BO 91’, ‘CoP 9301’ and ‘CoSe 92423’ in mid late maturing group at 120 cm row spacing. In early group, genotype ‘CoP 11436’ produced the higher tillers (1, 38000/ha), millable canes (1, 04800/ ha), cane (88.2 t/ha) and sugar yield (11.1 t/ ha). Genotype, ‘CoP 11438’ showed the higher brix (20.6) and pol (18.39%) per cent juice among test genotype, followed by standard check ‘BO 153’. Under mid late maturing group, higher germination count (46.2%), tillers (1, 52, 100/ha) and millable canes (1, 07800/ ha) was noticed due to the genotype ‘BO 155’ which was followed by the standard check ‘CoSe 92423’. However, ‘CoSe 11455’ recorded the highest cane (103.7 t/ha) and sugar yield (13.18 t/ha), followed by ‘BO 155’ in case of cane yield and CoSe 11453 in sugar yield. Among mid late genotype ‘CoSe 11453’, ‘CoSe 11454’ and standard check ‘CoP 9301’ obtained similar brix values of 20.7%. However, standard check ‘CoP 9301’ was found significantly superior to ‘BO 155’ with respect to pol and commercial cane sugar percent.

Effects of Varying Nitrogen Levels and Row Spacing on Fennel (Foeniculum vulgare mill.) Growth and Seed Yield

Effects of Varying Nitrogen Levels and Row Spacing on Fennel (Foeniculum vulgare mill.) Growth and Seed Yield

Simplification of selective imaging of dislocation loops: diffraction-selected on-zone STEM

ABSTRACT Contrary to the conventional belief that, in transmission electron microscopy (TEM), selective and sharp imaging of dislocation loops can be realized only by accurate tilting of a specimen from the condition that the symmetrical axis of incident electron beam distribution is parallel to a zone axis of the TEM specimen (on-zone condition), we demonstrate that selective dark-field (DF) imaging of dislocation loops at on-zone condition is possible with a scanning TEM (STEM) mode that uses an objective lens aperture to select a diffraction disk of interest. Diffraction-selected on-zone STEM (DsoZ-STEM) has been applied to selective DF imaging of dislocation loops with a short axis length of <2 nm in a single-crystal aluminum irradiated by argon ions and an electron beam at room temperature. It was found that a Kikuchi line enhances the contrast among the dislocation loops and the matrix of DsoZ-STEM images. DsoZ-STEM obeyed g·b invisibility criterion and showed good agreement with a typical visibility change of a dislocation line and a loop in conventional DF images with a specific pair of ± g. In addition, dislocation loops always showed much higher brightness in the inner side compared to the outer side in DsoZ-STEM images, simplifying the distinction of dislocation loops with apparently the same long-axis direction but different b. Thus, DsoZ-STEM can simplify the selective DF imaging for the determination of the number and the character of dislocation loops.

Effect of intercropping with legumes at different rates on the yield and soil physicochemical properties of Cyperus esculentus L. in arid land.

Intercropping has the potential to enhance yields and nutrient availability in resource-limited agricultural systems. However, the effects on crop yield nutrients and soil properties can vary considerably depending on the specific plant combinations and intercropping ratios used. In this study, the advantages and impacts of intercropping C. esculentus with legumes were investigated by measuring their biomass, nutrient content, and soil properties. The experiment included five intercropping treatments: monoculture of C. esculentus (MC), intercropping of C. esculentus with Medicago sativa L. (alfalfa) at row spacing ratios of 4:4 (4:4CM) and 8:4 (8:4CM), and intercropping of C. esculentus with Glycine max (L.) Merr. (soybean), also at row spacing ratios of 4:4 (4:4CG) and 8:4 (8:4CG). Our results demonstrated that all four intercropping treatments (4:4CM, 4:4CG, 8:4CM, and 8:4CG) significantly increased the biomass of C. esculentus by approximately 41.05%, 41.73%, 16.08%, and 18.43%, respectively, compared with monoculture cultivation alone, among which the 4:4CG treatment was optimum. However, no significant differences were observed in alfalfa or soybean biomass across different intercropping ratios. A notable increase was found in the total nitrogen (TN) and total phosphorus (TP) contents in the leaves, roots, and tubers of C. esculentus under intercropping, along with increased soil organic carbon (SOC), alkaline-hydrolyzed nitrogen (AN), available phosphorus (AP), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), and soil water content (SWC), and significantly reduced the soil pH. Among the intercropping treatments, the 4:4CG treatment also exhibited the most favorable soil properties. In particular, compared with MC, the 4:4CG treatment resulted in significant increases of 163.8%, 394.6%, and 716.8% in SOC, AN, and AP contents, respectively. The same treatment also led to significant increases of 48.34%, 46.40%, and 208.65% in MBC, MBN, and SWC, respectively. Overall, the findings suggest that the use of 4:4CG intercropping is an effective approach for sustainable farming management in Xinjiang.

Numerical study on stability of geosynthetic-encased stone column-supported embankments based on equivalent method

The application of geosynthetic-encased stone column-supported embankments (GESC-supported embankments) has garnered significant attention in geotechnical engineering, with limited investigations into their slope stability. In this paper, an equivalent method was proposed to establish GESC-supported embankment models through three-dimensional finite difference method (3D-FDM). Responses of factor of safety (FS) to arrangement tightness of GESCs (e.g., various column diameters, spacings, and quantities under constant area replacement ratio) and hoop effect of geosynthetic encasements (e.g., various geogrid strengths under different shear strengths of soft soil) were studied. For a given area replacement ratio, FS increased non-linearly with the increasing column quantity or the decreasing ratio of column spacing to diameter at high area replacement ratios. GESCs with smaller diameter and spacing proved to be more effective in improving slope stability, and an optimum ratio of column spacing to diameter was observed for practical use. Besides, FS increased linearly with geogrid strength at low geogrid strength levels, but an extremely lack of the shear strength of soft soils or the column quantity was unfavorable for the application of GESCs. Bending failure was the primary failure feature of GESCs under embankment loading, and the geogrid strength influenced slope stability through the bending capacity of GESCs.

Numerical investigation and parameter optimization on a rib-grooved liquid-cooled plate for lithium battery thermal management system

To increase the effectiveness of liquid-cooled battery thermal management systems (BTMS) in electric vehicles, a unique liquid-cooled plate with a discrete, inclined, and alternating arrangement of ribs and grooves inside the plate was invented during this study. A numerical study was carried on to analyze the thermal performance between this rib-grooved liquid-cooled plate and a conventional straight-channel one. Firstly, a battery module's 1D/3D electrochemical-thermal coupled model was constructed to analyze the thermal performance in the case of actual electrochemical heat production. Then numerical results were obtained by solving this coupled model with different plates. The results indicated that ribs effectively equalize the flows between different channels and multiple longitudinal swirl flows are formed due to grooves, which improves the liquid-cooled system's temperature control performance with a small increase in pressure drop. The maximum battery temperature is 0.74 °C lower, the temperature standard deviation of the contact surface is 0.18 °C lower, and the pressure drop is 55.37 Pa higher in the BTMS with the rib-grooved liquid-cooled plate than it is in the conventional one. After that, an orthogonal design of experiments was used to investigate the effect of four features, including rib-groove tilt angle, column spacing, row spacing, and rib-groove length, on the thermal performance and energy consumption of the battery module. The optimum structure of the rib-grooved liquid-cooled plate is obtained through range analysis: the rib-groove inclination angle is 45°, the row spacing is 13.5 mm, the column spacing is 11.5 mm, and the rib-groove length is 9 mm. This research on the rib-grooved liquid-cooled plate offers a fresh concept that considerably enhances its capacity to regulate the temperature of the liquid-cooled BTMS.

Evaluation of multi-camera images in different SfM-MVS based photogrammetric software and comparison of digital products in generating 3D city models

High-resolution 3D city modeling is generated using the oblique and vertical (nadir) imaging features of multi-camera systems. There are several SfM-MVS based photogrammetric software available. They enable high-resolution image processing and matching and acquire successful outcomes. The orientation of large photogrammetric blocks consisting of multiple sets of images and the accuracy of the 3D city models to be obtained vary according to the ability of the software using these approaches to solve large image matrix problems. In this study, a 3D city model was produced with vertical and oblique images obtained with UltraCam Osprey Mark 3 Premium camera in a selected application area in Kütahya city center. The main purpose of the study is to evaluate the point cloud, textured mesh model, digital elevation model, true orthophoto products and vectorial roof detail drawings via utilizing the vertical + oblique images with different SfM-MVS based photogrammetric software and to compare the results.

Effect of Water Conservation and Nitrogen Reduction on Root Growth and Yield in Spring Maize in Typical Sand Interlayered Soil

Given the low water and fertiliser use efficiency and the extensive distribution of sand interlayered soil in the Hetao irrigation district (HID), this study aimed to investigate the effects of different irrigation and fertilisation regimes on root parameters and yield in spring maize grown in sand interlayered soil. A two-year field plot experiment was conducted using the spring maize “Ximeng 3358” under three irrigation and nitrogen levels. Root length (RL), surface area (RS), diameter (RD), volume (RV), and length density (RLD), grain yield, and water use efficiency (WUE) were examined. Root growth was inhibited at the sand layer, with approximately 72.46–87.37% of the roots concentrated in the 0–40 cm soil layer. Notably, the proportion of roots in the bottom layer was 24.61–87.37% higher than that in the sub-bottom layer. Moreover, RL, RS, RD, and RV peaked in the medium irrigation and nitrogen fertilisation (I2F2) treatment. Furthermore, correlation analysis showed that the root parameters were significantly positively correlated with yield and WUE, with RS being most correlated to yield and WUE. Roots at a narrow row spacing of 20 cm (NR20) and at a depth of 10–20 cm were strongly correlated with yield and WUE. Conclusively, the I2F2 treatment can be used as the optimal combination of water and nitrogen for sand interlayered soil farmlands.

Error Analysis and Condition Estimation of the Pyramidal Form of the Lucas-Kanade Method in Optical Flow

Optical flow is the apparent motion of the brightness patterns in an image. The pyramidal form of the Lucas-Kanade (LK) method is frequently used for its computation but experiments have shown that the method has deficiencies. Problems arise because of numerical issues in the least squares (LS) problem minAx−b22, A∈Rm×2 and m≫2, which must be solved many times. Numerical properties of the solution x0=A†b = (ATA)−1ATb of the LS problem are considered and it is shown that the property m≫2 has implications for the error and stability of x0. In particular, it can be assumed that b has components that lie in the column space (range) R(A) of A, and the space that is orthogonal to R(A), from which it follows that the upper bound of the condition number of x0 is inversely proportional to cosθ, where θ is the angle between b and its component that lies in R(A). It is shown that the maximum values of this condition number, other condition numbers and the errors in the solutions of the LS problems increase as the pyramid is descended from the top level (coarsest image) to the base (finest image), such that the optical flow computed at the base of the pyramid may be computationally unreliable. The extension of these results to the problem of total least squares is addressed by considering the stability of the optical flow vectors when there are errors in A and b. Examples of the computation of the optical flow demonstrate the theoretical results, and the implications of these results for extended forms of the LK method are discussed.

Evaluation of rice collection samples &lt;i&gt;Oryza sativa&lt;/i&gt; L. in the Russian Far East

Relevance. Early-ripening varieties breeding is a constant task in the selection of rice in the Russian Far Eastern rice-growing zone, since the duration of the vegetation period is the main limiting factor in the region. Mediumand late-ripening forms, although more productive, often do not reach the full maturity phase. Early ripening varieties, as a rule, are less productive. Despite a certain negative relationship between productivity and precocity, it is necessary to select precisely these properties of rice plants.Methods. In the work, 157 samples of the updated rice collection Oryza sativa L. from 22 countries were studied. Varieties Primorsky 29 and Dolinny were used as control. Rice was sown in 2022 in a growing area in 1.54 m2 pots filled with soil. Each sample was placed in rows with row spacing of 15 cm, 10–12 plants in a row (randomized) in double repetition. Standard biometric measurements were taken. The sample size of each sample was 5–10 plants in replication. A total of 2194 plants were analyzed in the work.Results. Based on the first year results studying of the rice collection in the Primorsky Krai conditions, 39 accessions were identified that exceeded the standards in terms of main panicle grain mass and/or plant grain mass. Four of them exceed both standards in productivity (UkrNIS 9706, UkrNIS 3455, DON 7790, Nika Zulanzon). Nine early maturing accessions were identified with a vegetation period of 101–106 days, which is 2–8 days lower than the standards, which retained the productivity of panicles and plants at the control level (Zeravshanika, Onne Mochi, Mu 07-980, Mu-07-1055, Ussur, Uzros 24-24, No. 24, Kascade, Long Jing 15). Samples No. 24 are superior in main panicle grain mass, Mu 07-980 in grain mass of both control plants.

On the distance to low-rank matrices in the maximum norm

Every sufficiently big matrix with small spectral norm has a nearby low-rank matrix if the distance is measured in the maximum norm (Udell and Townsend, 2019 [7]). We use the Hanson–Wright inequality to improve the estimate of the distance for matrices with incoherent column and row spaces. In numerical experiments with several classes of matrices we study how well the theoretical upper bound describes the approximation errors achieved with the method of alternating projections.

Phantom study and clinical application of total-body 18F-FDG PET/CT imaging: How to use small voxel imaging better?

BackgroundConventional PET/CT imaging reconstruction is typically performed using voxel size of 3.0–4.0 mm in three axes. It is hypothesized that a smaller voxel sizes could improve the accuracy of small lesion detection. This study aims to explore the advantages and conditions of small voxel imaging on clinical application.MethodsBoth NEMA IQ phantom and 30 patients with an injected dose of 3.7 MBq/kg were scanned using a total-body PET/CT (uEXPLORER). Images were reconstructed using matrices of 192 × 192, 512 × 512, and 1024 × 1024 with scanning duration of 3 min, 5 min, 8 min, and 10 min, respectively.ResultsIn the phantom study, the contrast recovery coefficient reached the maximum in matrix group of 512 × 512, and background variability increased as voxel size decreased. In the clinical study, SUVmax, SD, and TLR increased, while SNR decreased as the voxel size decreased. When the scanning duration increased, SNR increased, while SUVmax, SD, and TLR decreased. The SUVmean was more reluctant to the changes in imaging matrix and scanning duration. The mean subjective scores for all 512 × 512 groups and 1024 × 1024 groups (scanning duration ≥ 8 min) were over three points. One false-positive lesion was found in groups of 512 × 512 with scanning duration of 3 min, 1024 × 1024 with 3 min and 5 min, respectively. Meanwhile, the false-negative lesions found in group of 192 × 192 with duration of 3 min and 5 min, 512 × 512 with 3 min and 1024 × 1024 with 3 min and 5 min were 5, 4, 1, 4, and 1, respectively. The reconstruction time and storage space occupation were significantly increased as the imaging matrix increased.ConclusionsPET/CT imaging with smaller voxel can improve SUVmax and TLR of lesions, which is advantageous for the diagnosis of small or hypometabolic lesions if with sufficient counts. With an 18F-FDG injection dose of 3.7 MBq/kg, uEXPLORER PET/CT imaging using matrix of 512 × 512 with 5 min or 1024 × 1024 with 8 min can meet the image requirements for clinical use.

Long-term detection of Hartmannibacter diazotrophicus on winter wheat and spring barley roots under field conditions revealed positive correlations on yield parameters with the bacterium abundance.

Monitoring of bioinoculants once released into the field remains largely unexplored; thus, more information is required about their survival and interactions after root colonization. Therefore, specific primers were used to perform a long-term tracking to elucidate the effect of Hartmannibacter diazotrophicus on wheat and barley production at two experimental organic agriculture field stations. Three factors were evaluated: organic fertilizer application (with and without), row spacing (15 and 50 cm), and bacterial inoculation (H. diazotrophicus and control without bacteria). Hartmannibacter diazotrophicus was detected by quantitative polymerase chain reaction on the roots (up to 5× 105 copies g-1 dry weight) until advanced developmental stages under field conditions during two seasons, and mostly in one farm. Correlation analysis showed a significant effect of H. diazotrophicus copy numbers on the yield parameters straw yield (increase of 453 kg ha-1 in wheat compared to the mean) and crude grain protein concentration (increase of 0.30% in wheat and 0.80% in barley compared to the mean). Our findings showed an apparently constant presence of H. diazotrophicus on both wheat and barley roots until 273 and 119 days after seeding, respectively, and its addition and concentration in the roots are associated with higher yields in one crop.