Abstract The objective of this work was to identify the resistance behavior of soybean (Glycine max) F1 populations with pyramided Rps genes, when subjected to inoculation with pathotypes of Phytophthora sojae. In 2020 and 2021, hybridizations were performed considering the presence of Rps genes from different loci in the parents. To characterize the F1 generation, pathotypes PS2.4, PS14.4, PS34.1, PS36.1, and CMES1608 were inoculated into the lateral branches of adult plants. The reaction to the pathotypes was evaluated in a greenhouse experiment, through the percentage of infected, dead, and healthy lateral branches. The study allowed identifying the virulent reaction of parents and their inoculated progenies. Progenies from virulent combinations of the same pathotype did not present new resistances. Resistance is increased by the complementarity of different Rps genes from the genotypes used to obtain the F1 progenies. Soybean F1 populations with pyramided Rps genes are an efficient genetic tool to help control Phytophthora sojae.

Abstract The objective of this work was to investigate genetic inheritance, selection gain, and simultaneous selection for multiple traits of interest in segregating wheat populations. Crosses were performed between genotypes 'Frontana', 'CD 1440', 'CD 105', and 'BRS Sabiá' and the F1 and F2 generations; the parents were sown in a field in 2020. From each plant, traits were obtained for germination in the spike, days from emergence to heading, plant height, number of tillers per plant, spike mass, number of spikelets per spike, grain mass per spike, number of grains per spike, and plant grain mass. In addition to the means, the following parameters were obtained: phenotypic, genetic, and environmental variances; broad-sense heritability; and selection gain. All traits showed quantitative inheritance controlled by many genes and influenced by the environment. In most traits, the segregated F2 populations closely resembled the parents, notably for sprouting in the ear, influenced by the environment. Days from emergence to heading and plant height showed a high heritability and good selection gains, while yield components showed variability for advancements in selection. Simultaneous selection reduced the number of superior individuals, reinforcing the importance of using multivariate methodologies. Thus, the genetic progress depends on strategies that consider quantitative inheritance and adopt multivariate approaches to maximize gains.

The objective of this study was the characterization of commercial cultivars, differentiating lines/cultivars of Phytophthora sojae carrying Rps (resistance Phytophthora Sojae) genes, inoculated with different pathotypes. Thirty-one differentiating soybeans (Glycine max (L.) Merrill) lines/cultivars carrying Rps genes and six commercial cultivars were evaluated for virulence pattern to PS2.4, PS14.4, PS36.1, PS34.1, and CMES1608 pathotypes. Inoculations were performed using the toothpick technique, with reaction evaluation about 15 days after infection, where the number of healthy, infected, and dead seedlings was quantified. There was a difference in resistance for the pathotypes, and the most virulent were PS34.1 and PS36.1. The Rps1k, Rps11, and Rp12 genes deserve to be highlighted by resistance to the PS34.1 pathotype and the Rps1k, Rps11, Rp12, and Rps8 genes to the PS36.1 pathotype. The line L77-1863 (Rps1b) showed resistance to the PS2.4 and PS14.4 pathotypes. The characterization of the genotypes allowed the updating of information about them and the identification of new possibilities of resistance sources.

ABSTRACT: The objective was to evaluate the effect of foliar application of commercial products based on extracts of Ascophyllum nodosum algae in two applications in phenological stages V4 and R1 and three in V4, R1 and R4 of soybean. The experiment was installed on 11/16/2022. Products based on A. nodosum algae (Acadian®, Phosamco Bio®, Bioalgas® and Phylgreen®) were applied at a dose of 1 L ha-1, in two and three applications at phenological stages V4 and R1 and V4, R1 and R4, respectively, organized into nine treatments. In the first application (12/19/2022), the weekly collection of two plants per plot began, obtained the plant height and green mass of the plant. At harvest, plant height, number of productive nodes per plant, plant mass, number of pods per plant, grain mass per plant and number of grains per plant were obtained from 10 random plants. The two central rows of each experimental unit were harvested and threshed, and together with the grain mass of the 10 plants, the thousand grain mass and grain yield were obtained. The data were subjected to analysis of variance and grouping of means. Applications of A. nodosum extracts provide greater height and mass in plants. Acadian®, Phosamco Bio®, Bioalgas® and Phylgreene® applied to the aerial part increase grain yield. Two applications of Phosamco Bio® provided superiority for all characteristics evaluated.

The lack and deterioration of the quality of water resources have made governments take educational measures and required society to rethink habits concerning the preservation and conservation of water quality. Thus, the present study aims to present the importance of spring preservation for water quality conservation as well as to develop a macroscopic environmental analysis of springs located in the state of Rio Grande do Sul, Brazil. Twenty springs were observed in two different periods of the year (May and November 2019), which had different economic activities: native forest – public domain; soybean, tobacco, and pig farming – private domain, in their surroundings. The study adopted five replications (different municipalities), and a macroscopic environmental analysis was carried out in each spring to classify them according to the extent of preservation. It was observed that most of the springs show “Good” and “Very good” preservation. However, it can be concluded that the economic activities developed in the surroundings do not interfere with spring preservation, and the methodology adopted is not recommended for the macroscopic environmental analysis in areas of native forest due to the characteristics considered.

- The objective of this work was to identify the most adapted and stable genotypes for dry mass and seed yield using the genotype plus environment interaction (GGE) biplot technique. The experiment was conducted in the municipality of Frederico Westphalen, in the state of Rio Grande do Sul, Brazil, in 2018, 2019, 2020, and 2021, using five lines and two cultivars of black oat, in a randomized complete block experimental design, with three replicates. The adaptability and stability of the genotypes, as well as their behavior in the environments, were evaluated using the GGE biplot. The seed yield of black oat genotypes is highly influenced by the environmental conditions over the four studied cultivation years. The UFSMFW 2-07 genotype stands out, but shows instability. The UFSMFW 2-07 and 'UPFA 21-Moreninha' genotypes show adaptability in specific years. Mega environments are formed for the dry mass trait in 2018 and 2021 and seed yield in 2018, 2020, and 2021, whereas, 2019 is considered the year for genotype discrimination.

The aim of this research was to study the genotype-environment interaction with a focus on decomposing the simple and complex parts of the interaction of black oat genotypes and clustering similar environments. The experiment was conducted at the Federal University of Santa Maria, Campus de Frederico Westphalen/RS (Brazil), in 2018, 2019, 2020, and 2021, using five lines and two cultivars of black oat in a randomized block experimental design. The traits evaluated were total dry mass and seed productivity. After verifying the presence of interaction between genotypes and environments, the interaction was decomposed into simple and complex parts. The UFSMFW 2-07 line stood out in terms of total dry mass and seed productivity. The total dry mass and seed productivity of black oat genotypes were highly influenced by environmental conditions over the four years of cultivation, highlighting the complexity of studying the genotype-environment interaction for more than one trait of interest at the same time.

ABSTRACT: This research evaluated the agronomic performance through mixed models, and determined the genetic divergence between black oat genotypes. The experiment was carried out at Federal University of Santa Maria, Frederico Westphalen/RS. Fourteen black oat genotypes were evaluated, being 11 lines developed by Breeding Program of University, and three commercial cultivars (IAPAR 61, UPFA 21 - Moreninha and, IPR Cabocla). We evaluated quantitative traits associated to plant height, cycle, dry mass yield and seeds yield; and 19 qualitative traits, being these morphological descriptors. The results showed that lines UFSMFW 2-05 and UFSMFW 2-07 stand out with characteristics such as early cycle, higher dry mass and grain yield. Divergence analysis revealed the formation of three distinct groups, indicating the presence of variability. These results suggested the potential for the development of new cultivars of black oat, presenting early cycle and good grain yield.

ABSTRACT The use of corn hybrids adapted to the soil and climate conditions of the cultivation region under adequate optimum plant density is a determining factor for the maximization of grain yield. In this sense, the objective was to evaluate the productivity of corn hybrids under two sowing densities during the 2020/21 crop season in the medium-high Uruguay region of the state of Rio Grande do Sul. The corn hybrids AS1555 PRO3, B2401 PWU, B2418 VYHR, B2612 PWU, BG7061 YHR, DKB235 PRO3, NS45 VIP3, NS73 VIP3, NS80 VIP3, P2501, P3016 VYHR, P3565 PWU and 30F53 VYHR were submitted to densities of 66,667 and 88,889 plants ha-1, in a randomized block design with ten replications. Corn hybrids showed superior grain yield when subjected to the density of 88,889 plants ha-1 in the medium-high Uruguay region of Rio Grande do Sul, surpassing in most cases the state and national average yield of harvest 2020/21. Most of the corn hybrids used present potential for cultivation at higher sowing density than their respective recommendations. Considering the superior productivity of hybrids NS80 VIP3, B2401 PWU and NS73 VIP3, their cultivation under conditions similar to those of the study is recommended.

AbstractWe conducted a study in a cemetery area covering 2608.53 m2 in the municipality of Nova Hartz, Metropolitan Region of the State of Rio Grande do Sul. Soil samples were collected to determine the physicochemical parameters of the local soil at nine points within the study area and at three different depths (0 cm, 50 cm, and 120 cm). Granulometry and saturated hydraulic conductivity of the soil were assessed, and chemical analyses for Cadmium, Cobalt, Copper, and Chromium were performed using the Atomic Absorption Spectrometry technique.The results revealed that the soil exhibited average values of 78.34% sand, 8.25% silt, and 13.41% clay, classifying it as sandy loam. The saturated hydraulic conductivity was measured at 5.7 × 10–4 cm s−1 across the profile (from 0 to 120 cm). Chemical analyses identified concentrations exceeding the allowed limits for Cadmium (points 1, 4, 5, 6, 7, 8, and 9), Cobalt (points 2, 3, 4, 5, 7, and 8), and Copper (points 4, 5, 6, 7, and 8), with only two values for Chromium (both at point 7). Some points exhibited concentrations above the maximum allowed values at multiple depths. Evaluating vertical distribution, Cadmium did not show depth variations, suggesting a possible natural origin unrelated to cemetery activities. Conversely, Copper, Cobalt, and Chromium displayed increased concentrations with depth. In conclusion, significant changes in concentrations of Cadmium, Cobalt, and Copper were observed, especially between depths of 0 and 120 cm.

ABSTRACT Considering the expressive number of commercial soybean cultivars available for cultivation in Brazil and the constant search for improvements in the production system, the objective was to evaluate the productive components and grain yield and to estimate the correlation between them in soybean cultivars sown in the northwest region of Rio Grande do Sul, during the 2019/20 harvest. Sixteen commercial soybean cultivars were sown under their respective plant density recommendations, in a randomized block design with three replications. At the end of the cultivation cycle, the following variables were evaluated: plant height; height of insertion of the first pod; number of nodes; number of pods with one, two, three and four grains; pods per plant; grains per plant; weight of thousand grains, and; grain yield. The cultivars BMX ZEUS IPRO, NS 5445 IPRO and NS 5700 IPRO presented the highest grain yields, mainly due to the high relationship between the number of pods and grains per plant and the weight of a thousand grains. The indirect selection of more productive genotypes can be carried out through the variables weight of thousand grains, number of pods, grains and nodes per plant, given the significant positive correlation between them.

Context: Counting traits are commonly measured in soybean research, however, the number of plants to be sampled per experimental unit needs to be standardized for estimating precision statistics from these traits, considering experimental designs; Objective: The current study evaluated the impact of plant variability for selected soybean agronomic traits; established the ideal sample size to estimate experimental precision statistics; and modeled the response of plant variability per experimental unit to forecast experimental precision statistics;Methods: Trials were conducted with 30 genotypes in highlands and 20 in lowland areas of Brazil. A complete randomized block design with three repetitions was used, measuring four counting traits in 20 plants per experimental unit, which represents a total of 9000 plants. From these experiments, trials with sampling scenarios from 1 to 100 plants per experimental unit were simulated;Results: Results showed an exponential decreasing response of the 95% confidence intervals as a function of the increase in sample size per experimental unit for all precision statistics, stabilizing when >= 21 plants per experimental unit were sampled.Conclusion: Twenty-one plants per experimental unit were considered representative for the soybean traits here studied. The response of the 95% confidence interval width to sample size enabled the creation of good-quality forecasting formulas and equations to predict experimental precision in experiments with soybean that evaluate these traits;Implications and significance: The sample size recommendations made in this work can be applied in similar experimentations.

Brazilian wheat farming is characterized by a high occurrence of seed-transmitted diseases that can cause significant damage to grain production. The objective of this study was to evaluate the influence of seed treatments on the physiological and sanitary quality of wheat cultivar seeds. Seeds from three commercial wheat cultivars (TBIO Sossego, TBIO Sinuelo, and TBIO Toruk) were used, along with four seed treatments (Control, Chemical, Biological, and Chemical + Biological). The physiological quality of the seeds was determined based on first germination count, germination percentage, quantification of abnormal seedlings, shoot and radicle length, whole seedling dry weight, and emergence velocity index (EVI). The sanitary quality was assessed using the Blotter test. Overall, the chemical treatment combined with the seeds of the TBIO Toruk cultivar provided better indices of physiological and sanitary quality.

The objective of this work was to select black oat genotypes using the MGIDI for simultaneous selection, comparing it with the Smith-Hazel index. The experiment was carried out in Frederico Westphalen/RS and Pato Branco/ PR, in a randomized block design, with three replications, with 9 genotypes tested. Days from emergence to flowering and maturation; cutting and plant height; number of tillers; panicle length; tiller, plant, panicle, panicle seed mass, green and dry; and seed yield were obtained. MGIDI selected the genotypes UFSMFW 2-01 and UFSMFW 2-04 for Frederico Westphalen and UFSMFW 2-07 and UFSMFW 2-04 for Pato Branco, which varied compared to the Smith-Hazel index in both environments. MGIDI was efficient in selecting the best black oat genotypes, showing desirable selection gains for most traits.

ABSTRACT: This study analyzed the response of the Bartlett test as a function of sample size and to define the optimal sample size for the test with soybean grain yield data. Six experiments were conducted in a randomized block design with 20 or 30 cultivars and three repetitions. Grain yield was determined per plant, totaling 9,000 sampled plants. Next, sample scenarios of 1, 2, ..., 100 plants were simulated and the optimal sample size was defined via maximum curvature points. The increase in sampled plants per experimental unit favors Bartlett test’s precision. Also, the sampling of 17 to 20 plants per experimental unit is enough to maintain the accuracy of the test.

Phytophthora root and stem rot, caused by Phytophthora sojae Kaufm. & Gerd is considered one of the main diseases causing soybean (Glycine max (L.) Merril) losses. The objective was to verify the virulence patterns in differentiating lines of P. sojae for inoculations in different phenological stages, in seedlings and lateral branches of adult plants. Seventeen differentiating lines were used and five P. sojae pathotypes with distinct virulence patterns were sinoculated. Inoculations were performed 10 days after emergence (DAE) in seedlings hypocotyl, and 35 DAE were inoculated in lateral branches of adult plants. The experiments were conducted in a completely randomized design with two factors, these being 17 genotypes and 5 pathotypes, in 6 replications. Evaluations were performed 10 days after inoculation counting the number of dead seedlings/branches. P. sojae characterization were classified as resistant, the criterion was up to 15% of dead seedlings/branches, moderately resistant when they presented between 16 and 31% of dead seedlings/branches, and susceptible when they presented from 31% of dead seedlings/branches. Inoculation results in seedlings and in lateral branches of adult plants, allowed the characterization of the genotypes for the different P. sojae pathotypes, presenting the same resistance classification regardless of the phenological stage. Strong and positive correlations between the stages prove the efficiency of the different phonological stage during the inoculation. In addition, phenological stage of inoculation can be adjusted according to the availability of time, seeds, or plants in research projects and in breeding programs.

Biometric techniques, including the principal component analysis, are commonly applied in soybean genetic divergence studies. However, the sample size used in such studies is often determined empirically, neglecting its potential impact on inference interpretation. Therefore, this study aimed (i) to analyze the response of principal components to the number of plants sampled per experimental unit (plot); (ii) to determine the multivariate representative sample size, and (iii) to construct a methodology to predict sample size for principal components as a function of the precision level defined a priori. Six experiments were performed in two locations in Rio Grande do Sul, Brazil, with three experiments being carried out in each location. All experiments were conducted using a complete randomized block design with three repetitions, and 20 soybean genotypes were utilized, resulting in 360 plots (60 plots per experiment). From each plot, twenty plants were sampled, totaling 7200 plants. A resampling bootstrap procedure was applied to the principal component technique for 10 biometric traits. Posteriorly, the sample size was defined based on predefined precision levels, and power logistic models were parametrized to predict the sample size per experimental unit. The precision of the eigenvalues obtained from the principal component analysis gradually improves with larger sample sizes. Eigenvalues that capture a higher variance tend to require smaller sample sizes for accurate estimation. The fitted models demonstrated satisfactory predictive ability in determining the optimal number of plants per experimental unit, serving as a complementary tool for defining sample size at the desired precision level. Eighteen plants per experimental unit are enough to estimate the eigenvalues of the first two soybean principal components reliably. The developed predictive methodology and sample dimensioning per experimental unit can support future research aimed at identifying divergent genotypes, making them useful tools for soybean plant breeding programs.

Empirical sampling can result in inaccurate estimates of the variance captured in canonical variances and, consequently, affect their scores. This circumstance interferes with the identification of divergence between genotypes, harming the selection of parents. This study had two main objectives: to analyze the response of canonical variables as a function of the number of plants sampled per experimental unit (plot); and to define a representative multivariate sample size based on the variance (in percentage) absorbed by the canonical variables. Experiments with soybean were performed in two locations in Rio Grande do Sul, Brazil, totaling three experiments per location. A complete randomized block experimental design was used, with three repetitions and 20 soybean genotypes, resulting in 360 plots. Ten traits were assessed in 20 plants per plot, totaling 7,200 plants. A bootstrap resampling procedure was applied for the canonical variable analysis based on ten biometric traits. Posteriorly, the sample size per experimental unit was dimensioned using nonlinear models and by defining the maximum curvature point through the perpendicular distances’ method. The estimate of the percentage variance retained in the canonical variables was sensitive to the number of plants sampled per experimental unit. This absorbed variance presents a decreasing potential response of its 95% confidence interval width to the sample size increase, associated with an improvement in precision when estimating the variance explained by the canonical variables, which tends to stabilize once 36 plants per experimental unit are sampled. Selecting insufficient sample sizes harms the identification of divergent genotypes. Sample size increase gradually improves the quality of the canonical variables’ variance estimates. Thirty-six plants per experimental unit are enough to estimate the variance explained in the first four canonical variables for soybean reliably. The sample size recommendations here presented will be useful for researchers in the field of genetic divergence who perform the canonical variables’ analysis for soybean trials, facilitating the obtention of reliable results, and, consequently, increasing the efficiency of soybean breeding programs.

Intermittent slow sand filters for household use have become an established technology that is efficient, simple, and affordable for water treatment. However, bio-clogging can seriously limit hydraulic efficiency and water quality in this treatment system. Therefore, the use of new techniques for studying clogging in slow sand filters has been proposed. This study aimed to evaluate biological clogging using an enzymatic approach, considering also hydraulic aspects and water quality. Six filtration columns with two different granulometric characteristics (fine sand and medium sand) were operated with a downward flow and intermittent flow regime for 120 days. The bio-clogging of the filter media was evaluated considering the presence of esterase enzymes through the degradation of fluorescein diacetate (FDA). So, daily raw and filtered water analyses were performed for physical and chemical characteristics and hydraulic monitoring. The two granulometric characteristics used did not significantly differ between physical and chemical aspects of water quality within the parameters analyzed. The filters showed an average efficiency of turbidity removal of 79.6 % and 80.5 % for fine and medium sand, respectively. The enzymatic assay revealed the existence of microbiological activity throughout the extent of the filters in both granulometric configurations used. The results indicated a potential risk of contamination of the filtered water. The FDA technique proved to be an exciting tool in evaluating biological clogging in intermittent slow sand filters.

ABSTRACT: This study analyzed the interference of sample size on Tukey’s test for non-additivity and found the sample size to optimize the test for soybean grain yield. Six experiments were conducted in a completely randomized block design with either 20 or 30 cultivars and three repetitions of each treatment. Grain yield was determined per plant, totaling 9,000 sampled plants. Next, sample scenarios up to 100 plants were simulated, estimating F statistic for a degree of freedom of the error in each scenario. After that, the optimal sample size was defined via power models and maximum curvature point. Results showed the number of sampled plants per experimental unit influences the estimates of Tukey’s test for non-additivity. Also, the sampling of 14 to 19 plants per experimental unit allows for maintaining the accuracy of the test.