Insertion Height Research Articles

Genome-Wide Association for Morphological and Agronomic Traits in Phaseolus vulgaris L. Accessions.

Exploring genetic resources through genomic analyses has emerged as a powerful strategy to develop common bean (Phaseolus vulgaris L.) cultivars that are both productive and well-adapted to various environments. This study aimed to identify genomic regions linked to morpho-agronomic traits in Mesoamerican and Andean common bean accessions and to elucidate the proteins potentially involved in these traits. We evaluated 109 common bean accessions over three agricultural years, focusing on traits including the grain yield (YDSD), 100-seed weight (SW), number of seeds per pod (SDPD), number of pods per plant (PDPL), first pod insertion height (FPIH), plant height (PLHT), days to flowering (DF), and days to maturity (DPM). Using multilocus methods such as mrMLM, FASTmrMLM, FASTmrEMMA, ISIS EM-BLASSO, and pLARmEB, we identified 36 significant SNPs across all chromosomes (Pv01 to Pv11). Validating these SNPs and candidate genes in segregating populations is crucial for developing more productive common bean cultivars through marker-assisted selection.

Experimental unbalance: reflections on genetic parameters and corn selection gain

Genetic progress depends on the components of variance and genetic parameters. In this context, the objective of this work was to identify the maximum allowed percentage of experimental imbalance in the estimation of variance components, genetic parameters and selection gain in intervarietal corn hybrids. The experimental design used was randomized blocks, with 60 corn hybrids with three replications. Random subsets of data were created in order to express unbalance scenarios of the phenotypic matrix, we obtained 9 scenarios (0, 10, 20, 30, 40, 50, 60, 70 and 80% unbalance).Thus, the genetic variance of the paternal genitor, the genetic variance of the maternal genitor, additive variance, individual phenotypic variance, narrow-sense heritability of intervarietal additive effects for the paternal genitor were estimated, narrow-sense heritability of intervarietal additive effects for the maternal genitor, narrow-sense heritability, broad-sense heritability, genotypic variation coefficient between progenies and variation coefficient residual. Narrow sense heritability reveals high magnitude for the characters cob mass and hundred grain mass. Maternal effect is expressed through ear insertion height, ear grain mass, cob mass and diameter, number of rows, ear mass and length, and grain yield. The imbalance inflates the variance components and genetic parameters for the highlighted characters. It supports 10% imbalance in the data matrix without compromising the reliability of the estimates. Pronounceable selection gains are obtained for grain yield based on pressures of 1 and 5%. An unbalance of 10% is supported in the selection gain for cob mass, ear length and hundred grain mass.

Assessment of Bone Thickness at the Infra Zygomatic Crest Region for Various Orthodontic Miniscrew Implant (OMSI) Insertion Angles: A Cone-Beam Computed Tomographic Study.

To evaluate the infrazygomatic crest (IZC) bone and develop guidelines for the optimum placement of orthodontic miniscrew implants (OMSIs) along the distobuccal root of the permanent maxillary first molar. Bone thickness of the IZC region of 50 young adults (25 males and 25 females) aged 18-30 years were evaluated using cone-beam computed tomography images. The infrazygomatic bone thickness along the distobuccal root of the permanent maxillary first molar was assessed at various insertion angles (40° to 75° i.r.t the maxillary occlusal plane) with an increment of 5°. Student's t-test was used to compare the IZC bone thickness and height at the orthodontic miniscrew insertion site for males and females on the right and left sides. The bone thickness of the IZC region above the distobuccal root of the permanent maxillary first molar was estimated between 4.39±0.25 mm and 9.03±0.45 mm for insertion angles from 40° to 75° to the maxillary occlusal plane. The corresponding OMSI insertion heights were 17.71±0.61 mm to 13.69±0.75 mm, respectively, above the maxillary occlusal plane. There were statistically significant gender and side-wise variations in bone thickness at the IZC area and insertion height. The safe position for OMSI placement at the IZC was 13.69-16 mm from the maxillary occlusal plane with an insertion angle between 55° and 75°. These parameters provide the optimum placement of OMSIs along the distobuccal root of the permanent maxillary first molar.

AGRONOMIC EFFICIENCY OF HUMIC AND FULVIC ACIDS, FUNGI, BACTERIA, USED IN THE CULTURE OF THE SECOND SAFRA

The implementation of the research took place in the period corresponding to the second harvest of the 2022/2023 agricultural year, by the company Pesquisa e Consultoria Agronômica, in geographic coordinates located at 28°18'18'' south latitude, 38°15' 21'' longitude west. The research aimed to evaluate, through the application of biological products, whether it would be possible to obtain more vigorous and productive plants, in order to quantify their agronomic efficiency, thus validating the use of new technological alternatives in nutritional management in corn cultivation. The P3707 hybrid was used and the composition of the treatments is T1: Control treatment with Azospirillum brasilense bacteria (AbV5) (0.100 L ha-1) (planting juice); T2: Azospirillum brasilense (AbV5) (0.100 L ha-1) + Trichoderma asperellum BV10 (0.100 L ha-1) + Bacillus amyloliquefaciens (0.200 L ha-1) (planting juice); T3: Azospirillum baldaniorum, Bacillus amyloliquefaciens; Bacillus proteolyticus and Pseudomonas aeruginosa (0.200 kg ha-1) (planting juice); T4: Azospirillum brasilense (AbV5) (0.100 L ha-1) + Humic and fulvic acids, Azospirillum baldaniorum, Bacillus amyloliquefaciens; Bacillus proteolyticus and Pseudomonas aeruginosa (0.200 kg ha-1) (TS); T5: Humic and fulvic acids, Azospirillum brasilense (AbV5) (0.400 L ha-1) + Azospirillum baldaniorum, Bacillus amyloliquefaciens; Bacillus proteolyticus and Pseudomonas aeruginosa (0.400 kg ha-1) (planting juice); T6: Humic and fulvic acids, Azospirillum brasilense (AbV5) (0.100 L ha-1) + Azospirillum baldaniorum, Bacillus amyloliquefaciens; Bacillus proteolyticus and Pseudomonas aeruginosa (0.400 kg ha-1) (TS). The technological variables evaluated include plant population at the phenological stage (R5), plant height (V3 and R1), root diameter (V3 and R1), insertion height of the first ear, number of ears per plant, root volume (V3 and R1 ), fresh mass of roots (V3 and R1), dry mass of roots (V3 and R1), thousand grain weight, kilogram productivity per hectare. The data obtained were subjected to analysis of variance and the means of the treatments compared using the Tukey method of separation of means, using R Core Team (2019) with a significance of 5%. The application of humic acid, fulvic acid, fungi, bacteria in seed treatment provided gains in fresh aerial part mass, grain weight and greater productivity of the corn crop.

Competitive response of maize against glyphosate-resistant Digitaria insularis and Eleusine indica

To optimize integrated weed management, it is essential to understand the competitive ability of maize hybrids with new traits when coexisting with the weed community. Thus, the aim of this study was to evaluate the competitive ability of the maize against E. indica and D. insularis weeds under greenhouse (controlled conditions) and in the field by additive and replacement series designs, with different densities for each condition. In greenhouse experiments, maize coexisting with E. indica resulted in negative relative growth for leaf area and shoot dry mass, indicating damage to both species. However, maize with D. insularis did not exhibit negative relative growth, suggesting a different interaction. The analysis of relative competitiveness and aggressiveness revealed significant values for maize with D. insularis, indicating a competitive relationship. In contrast, maize with E. indica showed non-significant values, suggesting a less competitive interaction. In field experiments, the full model and reduced models showed good fit to the data, with non-significant differences between them, indicating that the interference of these weed species on maize yield were similar. The Principal Component Analysis identified four principal components. For PCs 1 and 2, chlorophyll-related variables exhibited a high relative contribution, showing a positive correlation with cases involving high density of D. insularis. Variables related to ear insertion height, plant height, stem diameter, and stand of plants had greater relative importance for PC 1, especially for cases with higher density of E. indica. This highlights the resilience of maize to competitive conditions and suggests that its capacity for rapid growth in height makes this crop effective in competition for light, even against other C4 species.

Effect of different doses of nitrogen and inoculation with Azospirillum brasilense on the productive characteristics of maize

This study assessed the effects of different nitrogen doses on maize crops, with and without the inoculation of Azospirillum brasilense. The experiment was carried out during the 2020/2021 harvest season in the administrative department of Concepción, district of Horqueta, Paraguay, at the coordinates of 23°14'31.7" S and 56°53'05.9" W. The experiment followed a randomized complete block design (RCBD) arranged in a factorial design (4 X 2). Factor A included nitrogen doses (0, 40, 80, and 120 kg ha-1), while factor B corresponded to the bacterial inoculation (with and without A. brasilense). The experiment was performed in three replications; each experimental unit (EU) was 22.5 m2. The study evaluated the following characteristics: plant height, cob insertion height, cob length and diameter, weight of 1000 kernels, and kernel yield. The data were analyzed using analysis of variance (ANOVA), and the averages were compared using Tukey's test at a 5% probability of error. Regression analysis was also carried out during the study. The experiment results demonstrated that increased nitrogen levels positively affected the measured characteristics, fitting a quadratic model, except for cob insertion height. Inoculation with A. brasilense significantly increased corn growth and productivity. The interaction of both factors produced a significant increase in cob length. Based on the experiment results, applying 104.30 kg ha-1 of N in combination with A. brasilense inoculation is recommended for improved maize production.

Evaluation of Optimal Insertion Sites and Angles for Orthodontic Mini-Implants at the Anterior Nasal Spine Region Based on Cone-Beam Computed Tomography

Background: To infer the optimal angulation and height level of mini-implant insertion in the anterior nasal spine (ANS) region from alveolar bone depth (BD) and labial cortical bone thickness (CBT) through cone-beam computed tomography (CBCT), the influences of sex, age, and growth pattern on BD, CBT, and the starting point of the ANS were examined. Material and methods: BD and CBT were measured on CBCT median sagittal images at specific angles (0, 15, 30, 45, and 60 degrees) to simulate the angulation of insertion. The height level of the first axial image with obvious bone ridge was recorded as the start of ANS. Results: The average height of ANS start was 9.42 mm from the alveolar bone crest between the central incisors. The variations in height level and insertion angle combined, or either of them individually, significantly influenced BD and CBT, demonstrating overall decreasing trends (p < 0.001). BD was not influenced by sex, age, or growth pattern (p > 0.05). However, CBT was found to be correlated with sex and growth pattern, while the height level of ANS start was associated only with growth pattern, particularly in hypodivergent patients (p < 0.05). Conclusion: The recommended insertion height level is 14–16 mm from the alveolar bone crest and the recommended angulation is 30–45°. An innovative inequity in the relationship between a certain height level and the insertion angulation is proposed.

Variations in the cystic duct: frequency and the relationship among insertion sides and heights on the bile duct.

Evaluation of the cystic duct anatomy prior to bile duct or gallbladder surgery is important, to decrease the risk of bile duct injury. This study aimed to clarify the frequency of cystic duct variations and the relationship between them. Data of 205 patients who underwent cholecystectomy after imaging at Sada Hospital, Japan, were analyzed. The Chi-square test was used to analyze the relationships among variations. The lateral and posterior sides of the bile duct were the two most common insertion points (92 patients, 44.9%), and the middle height was the most common insertion height (135 patients, 65.9%). Clinically important variations (spiral courses, parallel courses, low insertions, and right hepatic duct draining) relating to the risk of bile duct injury were observed in 24 patients (11.7%). Regarding the relationship between the insertion sides and heights, we noticed that the posterior insertion frequently existed in low insertions (75.0%, P<0.001) and did not exist in high insertions. In contrast, the anterior insertion coexisted with high and never low insertions. Spiral courses have two courses: anterior and posterior, and anterior ones were only found in high insertion cases. The insertion point of the cystic duct and the spiral courses tended to be anterior or lateral superiorly and posterior inferiorly. Clinically significant variations in cystic duct insertions are common and surgeons should be cautious about these variations to avoid complications.

Inoculação com fungo micorrízico arbuscular Rhizophagus clarus em tomateiro proporciona aumento de produtividade em cultivo orgânico

ABSTRACT: Organic agriculture comprises farming practices that discard synthetic pesticides and fertilizers. Tomato production demands huge amounts of fertilizers and pesticides. Improving efficiency of the inputs allowed for organic tomato production is a challenge to upgrade yields. Thereby, we studied the effects of the inoculation of the arbuscular mycorrhizal fungus (AMF) Rhizophagus clarus, supplying rock thermophosphate and bioactivator, alone or associated, on tomato development and yield. The experiment was achieved in a greenhouse using undetermined tomato cv. BRS-Nagai sown in polystyrene trays and afterwards transplanted to pots. Treatments included R. clarus; thermophosphate (TH) (130 g/pot); bioactivator (PenergeticK® + Penergetic®) (BI); R. clarus + TH; R. clarus + BI; R. clarus + TH+ BI and TH + BI and control (CO). From the flowering onset, plant height, height of insertion of first truss, trusses space, length, and also the diameter and fresh weight of ripe fruits of the three first trusses were assessed. AMF colonization in the roots and macronutrients in leaves and petioles were also measured. Trusses spacing variable was affected by mycorrhiza and thermophosphate. R. clarus inoculation incremented 10 and 31.85% of fresh mass of ripe fruits and mass of ripe fruits per plant, respectively. Soluble solids contents in fruits and N, P and K in the leaves and petioles were similar among treatments. AMF colonization decreased on thermophosphate fertilized plants and increased in bioactivator treatment. Results showed that root inoculation with R. clarus promoted better plant development and yield and may be used as biological inoculant mostly on organic tomato production.

Boron Fertilization Improves the Agronomic Performance of Soybean Genotypes in the Brazilian Cerrado

Currently, Brazil is the largest producer and exporter of soybeans in the world. Most of this cultivation is concentrated in the Cerrado region, which has soils with low boron levels. Boron performs functions that are directly linked to plant performance. The objective of this study was to evaluate the agronomic performance of soybean cultivars with and without boron fertilization. Two field experiments were carried out in the agricultural years 2018/2019 and 2019/2020. Each experiment was carried out in a randomized block design with four replications and 10 soybean cultivars (Desafio, Foco, Bonus, Maracaí, 7067, 7110, 7739, 8372, 7100, and Population). Boron fertilization was carried out at the V3 stage of the crop using ulexite (10% of boron) at a rate of 3194 kg ha−1 and 0.0 kg ha−1 of B. The application of boron to the soil increased plant height, pod insertion height, number of branches, main stem diameter, and number of pods per plant, in addition to increasing the cycle of these cultivars. The cultivars 7110, 7739 and Desafio did not statistically differ in terms of grain yield in response to boron fertilization. The cultivars Foco, Bonus, Maracaí, 7067, 8372, 7100, and Population responded favorably to this fertilization. Furthermore, genetic breeding programs incorporate advanced strategies, such as the use of boron fertilization, in order to improve the performance of the selected genotypes. Implementing boron fertilization as an integral part of breeding programs helps not only to achieve high-yielding cultivars but also to optimize key agronomic traits. This integrated approach not only boosts breeding research but also provides a solid basis for sustainable and efficient agricultural practices.

INOCULAÇÃO E APLICAÇÃO DE DIFERENTES DOSES DE Azospirillum brasilense E SUA INFLUÊNCIA NO DESENVOLVIMENTO DA CULTURA DO MILHO

Benefits in grain productivity, with low economic cost, ease of application, without causing toxic damage to the environment and with high potential for crop response, are target points in research involving the cultivation of corn. In this context, the present study aimed to evaluate the effect of inoculation of Azospirillum brasilense on the vegetative structures of the corn crop, envisioning an increase in the development of the plant. The experimental design used was completely randomized, with six treatments and four replications, totaling 24 experiments. Seeds were inoculated with A. brasilense in different doses of the commercial product (0 - 1000 mL), where the plant height (AP), ear insertion height (AIE), stem diameter (DC), total number of leaves (NTF) and number of leaves below the first ear (NFAE), were evaluated. The inoculation of corn seeds based on A. brasilense strain Ab-V5 promoted influence on some biometric variables, with an increase in the total number of leaves (NTF), plant height (AP) and height of ear insertion (AIE) for the evaluated hybrid, resulting in increments in its vegetative development. The dosage of 549 mL per hectare was considered as favorable to result in greater amounts of total leaves (NTF) in the plant, according to the adjustment of the proposed model. The results emphasized that inoculation with this strain is a valid technique and is increasingly used by farmers, and its study is a contributing factor for improvements in agronomic parameters.

Soybean Population Management Seeking Greater Grain Productivity

Objective: The objective of this research was to evaluate plant growth, soybean grain yield and production cost depending on the use of different populations. Theoretical reference: Among management practices, plant population is an extremely important stage for the establishment of soybean crops. In many cases, just changing the plant population is enough to result in high gains in crop grain productivity. Methodology: A randomized block design was used, with four treatments and four replications. The treatments consisted of densities of 200, 250, 300 and 350 thousand seeds ha-1. Plant height, insertion height of the first pod, number of pods per plant, number of grains per pod, mass of one thousand grains and grain productivity were evaluated. Results and conclusion: Populations influenced grain productivity, with the highest productivity being achieved in the population of 250 thousand, 5905 kg ha-1. It was concluded that sowing density affects the number of pods per plant and soybean grain productivity. The density of 250 thousand seeds ha-1 was the one that provided the highest productivity of soybeans and the lowest sowing cost. Research implications: Determining the best population of soybean plants in different locations is essential to reduce producer costs. Originality/value: Most research works focus on the use of inputs, disregarding that the plant population can affect crop performance and production costs.

Mechanical performance of concrete canvas reinforced with insert-bar structures under quasi-static and impact loading

Concrete canvas (CC) is a promising composite based on a combination of three-dimensional fabric and cement-based powder, with the comprehensive advantages of easy storage and transport, convenient construction, rapid strength development, and low dust pollution. In civil and military engineering, interest and exploration work within the field of CC have been ongoing for many years. While external measures exist to enhance the mechanical properties of CC, substantial internal measures are still lacking. In this paper, an internal stiffening strategy was proposed by coupling warp-knitted spacer structure with a series of insert-bar structures, attempting to improve the mechanical performance of CC. The reinforcing effect of flexible bar stiffeners were investigated through quasi-static bursting test and impact test. Damage morphology analysis was then performed to reveal the progressive failure mechanism. The obtained results demonstrated that flexible bar stiffeners with low modulus were highly beneficial reinforcements for CC due to their favorable synergy and great stress dissipation capacity. The load-bearing capacity and toughness of CC were increased with the insertion height and groups of bar combination. The vertical combination could further enhance the penetration resistance by altering stress transfer.

Performance of white corn hybrids intended for grits in different production environments

The Brazilian market has few hybrids intended for grits production, in particular, due to companies' lack of interest in developing new white corn hybrids due to the low proportion of cultivation in yellow corn hybrids. Another complicating factor is the genotype × environment interaction for recommending superior genetic materials. For this reason, this work aimed to evaluate agronomic characteristics and grits yield of commercial white corn hybrids IPR 127 and Dow 120009HW in different production environments. The assays were carried out in the municipalities of Rolândia-PR (Brazil), Campo Novo do Parecis-MT (Brazil), and Naranjal-PY (Paraguay), in a randomized block design, with four replications in a 2 × 3 factorial scheme (white corn hybrids × production environments). The analyzed variables were plant height, main cob insertion height, lodging and breakage, grain yield, and grits yield. Data were submitted to variance analysis by F test (p&lt;0.05) and means compared by Tukey's test, 5% probability of error, and principal component analysis (PCA). The production environments influence the performance of white corn hybrids intended for grits, IPR 127, and Dow 12B0009WH. The variables plant height, main cob insertion height, lodging and breakage, and grits yield were favored in cultivation in the municipality of Naranjal. The grain yield variable was higher in cultivation in Rolândia, and Campo Novo do Parecis municipalities. The white corn hybrid IPR 127 has a higher grits yield than the hybrid Dow 12B0009WH, in addition to greater stability of this variable depending on the production environments.

Diversidade genética e fenotípica de uma população de plântulas de moringa a partir de descritores morfológicos

Moringa (Moringa oleifera Lam. - Moringaceae) is a plant originating in India, which has been widely cultivated in different regions of the world, especially due to the nutritional properties of its leaves, which are of high economic, medicinal and industrial interest. However, there are no reports on the genotypic and phenotypic diversity of moringa seedlings cultivated in the Central-West region of Brazil. This study aimed to characterize a population of moringa seedlings using different qualitative morphological descriptors. A population consisting of 1,263 28-day-old moringa plants was initially classified and separated into four distinct phenotypic groups based on hypocotyl color [seedlings with hypocotyls colored green (100% green), ¾ green (75% green and 25% purple ), ¾ purple (25% green and 75% purple), and purple hypocotyl (100% purple)]. Initially, the seedling emergence rate and the frequency of occurrence of the different hypocotyl color classes in the total population were evaluated. Subsequently, 10 morphological descriptors were evaluated in each group of plants with different hypocotyl color. The plant emergence rate was 74%, indicating the adequate physiological quality of the seeds. The separation of the population into four phenotypic groups based on the color of the hypocotyl allowed us to separate 432 plants (34.2%) with a green hypocotyl, 480 plants (38.0%) with a ¾ green color, 336 plants (26.6% ) ¾ purple in color and 15 plants (1.2%) with purple hypocotyls. The results reported that of the ten morphological descriptors evaluated, only the type of insertion of the first pair of leaves (TI_1F) and the height of insertion of the first leaf (AI_1F) have significant differences (P &lt; 0.05) between the different phenotypic groups of seedlings. moringa. Seedlings from the phenotypic group with purple or ¾ purple hypocotyls have the entire insertion of the first pair of daughters of the opposite type, while seedlings with green and ¾ green hypocotyls have, respectively, 25% and 42% of the plants with the insertion of the first pair of alternating leaves. Seedlings with purple hypocotyls have a higher insertion height of the first leaf (AI_1F) when compared to green and ¾ green seedlings. Highly significant and negative correlations were obtained between TI_1F and DC (–0.99, P &lt; 0.05) and VR (–0.96; P &lt; 0.05). Highly significant and positive correlations were obtained between AI_1F and DC (0.96; P &lt; 0.05). It can be stated that there is genetic and phenotypic variability within a population of moringa seedlings, and the distinct phenotypic groups separated based on hypocotyl color have some characteristics or morphological descriptors typical of their group.

ASSESSMENT OF THE USE OF AN INDIVIDUAL TOOL FOR KNEE ARTHROPLASTY

Objective. On the basis of comparative radiometric analysis, before and after surgery, to assess the accuracy of the knee arthroplasty with an individual instrument. Methods. The analysis of knee arthroplasty of 26 patients operated with a special instrument was performed. Age: 50–59 years — 6, 0–69 — 12, 70–79 — 5, 80 and older — 3 patients. Men — 3, women — 18. Before the operation performed a computed tomography of the lower extremities, and after operation radiography of the lower extremities completely with the vertical positions of the feet. Patient specific instrument made according to the original method. The results of the analysis were performed by comparing X-ray parameters before and after operations: 1) position of the mechanical axis in the frontal plane on the plateau of the tibia in percent; 2) medial tibial resection angle to the mechanical axis; 3) the size of the components of the endoprosthesis (femoral, tibial and liner height). Results. Deviations in the values of the medial tibial and of the lateral femoral angles between the planned and actually obtained value was an average of 0.7 %, which can be considered a high indicator of the accuracy of the implant position. The position of the mechanical axis of the limb after the operation differed from the planned by a little more than 0.9 %. The dimensions of the endoprosthesis components and the height of the tibial insert fitted to the patients matched the planning results in 100 % of the cases, with the tibial insert height being 9 mm in all cases. The use of an individual tool made it possible to reduce the time of the operation, not to open the bone marrow canal of the thigh Conclusions. The use of the original individual tool for knee arthroplasty provided a high precision to install the components of the arthroplasty.

Correlations of agronomic characteristics of soybean cultivated with the use of organomineral fertilizers

The use of correlations can identify the traits correlated with soybean grain yield. Therefore, the objective of this study is to use path analysis to examine how agronomic traits influence grain yield in soybeans, taking into account different doses and sources of organominerals used in cultivation. The experimental design used was randomized blocks arranged in a sub-subdivided plot with three replications. In the plots, the treatments consisted of two soybean cultivars (BMX Bônus IPRO and BMX Olimpo IPRO), and in the subplot, the treatments consisted of three phosphate fertilizers [two organomineral fertilizers manufactured and a phosphate fertilizer (simple superphosphate)]. The subplot used doses of 0 (control), 50, and 100 kg ha-1 of P2O5. At full flowering, the relative chlorophyll index was evaluated. At physiological maturity, plant height, first pod insertion height, number of stems, pod number, number of grains per pod, thousand-grain mass, and grain yield were evaluated. The plant height variable presented the greatest positive direct effect on the soybean yield cultivated using organomineral fertilizers.

Optimum sowing density arrangement to maximize linseed agronomic performance

The objective of this work was to verify if it is possible to identify the optimum sowing density arrangement to maximize the productive performance of linseed. The experiment took place in the years 2020, 2021 and 2022 in the municipality of Augusto Pestana. The experimental design used was randomized blocks organized in a three-factor scheme, with six sowing densities (30, 60, 90, 120, 150 and 180 seeds per linear meter), two spacing between rows (Arrangement I: 0.18 m and Arrangement II: 0.54 m) and three seasons (2020, 2021 and 2022), with treatments arranged in four replications. The following variables were measured: plant height (PH, cm), height of insertion of the first capsule (HIFC, cm), stem diameter (SD, mm) and thousand grain weight (TGW, g). Grain yield (GY, kg ha-1) was evaluated by harvesting the four central rows of each experimental unit. Then, analysis of variance was performed at 5% significance by the F test. Tukey's test was applied to compare the means of qualitative treatments, at 5% probability. To verify the effects of sowing density, regressions were used. The spacing of 18 cm between rows promoted the highest yield performance of the row, regardless of the seed density used. The diameter of the stem responded positively to the sowing density up to the limit of 90 seeds per linear meter.

Doses and application timing of boron on the agronomic characteristics of corn

Corn cultivation holds great economic importance in Brazil, as it is grown throughout the country, covering approximately 21.5 million hectares annually, with a production of 113 million tons in the 2021/2022 harvest. However, crop production is directly linked to plant nutrition, and boron (B) is one of the essential micronutrients for plant development. Its deficiency imposes limitations on Brazilian agricultural crops. Therefore, the objective of this study was to evaluate the vegetative and productive characteristics of corn in response to the application of different doses of boron at different application timings. The experimental design used was completely randomized, in a 3x5 factorial scheme, with 4 replications, consisting of the combination of 5 doses of B (0, 0.5, 1, 2, and 4 kg ha-1) applied in the sowing furrow and at the V4 and V7 phenological stages. Plant height, first ear insertion height, stem diameter, number of rows per ear, number of grains per row, number of grains per ear, ear weight, grain weight per plant, and 100-grain weight were evaluated. No significant differences were observed between the doses and/or timing of boron application in the hybrid corn used in this study.

Agronomic performance of green corn at different sowing times and nitrogen doses

The present study aimed to identify the best sowing time and the best nitrogen dose in topdressing of the corn crop for "green ear" consumption. The experiment was conducted between October 2018 and June 2019 in a commercial crop, in Ipameri, Goiás, Brazil. The soil in the experimental area is classified as dystrophic Red-Yellow Latosol with clayey texture. The experimental design used was the randomized blocks, in a 5 x 5 factorial scheme, with five sowing times [1st (10/19/2018); 2nd (11/29/2018); 3rd (01/08/2019); 4th (02/18/2019) and 5th (03/28/2019)], implemented with 40 days intervals, after the first sowing, and five nitrogen doses (0, 50, 100, 150, and 200 kg ha-1), with four replicates. The following factors were evaluated for each sowing time: relative chlorophyll index, leaf dry mass, leaf nitrogen content, plant height, first ear insertion height, ears diameter and length, the total yield of ears with husks, the yield of commercial ears without husks and grain yield. The data were submitted to the analysis of variance (F-test). The sowing times and nitrogen doses in topdressing influenced the leaf nitrogen content, relative chlorophyll index, leaf dry mass, yield, and most of its components. Thus, it can be indicated that the best time for sowing corn for fresh consumption is in October (1st sowing time), and the estimated nitrogen dose in topdressing to obtain the maximum yield is 160 kg ha-1 of nitrogen.