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The growth of cover crops can contribute to the increase in phosphorus content at depth by root decomposition. The aim of this work was to verify the effect of cover crops on soil phosphorus availability and use by successive plants, and the accumulation of soil P in a no-tillage system conducted for 14 years. This research was carried out during the 2016/2017 and 2017/2018 crop seasons, whose treatments have been installed and maintained since 2003. The experimental design was a randomized block design, and the plots consisted of spring crops: pearl millet, forage sorghum, sunn hemp, and additionally, a fallow/chiseling area. The evaluation of available P was determined by P fractionation. In general, in the two years of evaluation, the accumulation of P in the shoot dry matter was higher in sunn hemp growth, on average 25% higher than pearl millet in 2016 and 40% higher than sorghum in 2017. The highest contents of labile inorganic P were in the sorghum-soybean and fallow/chiseling-soybean successions, with values higher than 50 mg kg-1 of P in the 0-0.1 m soil layer. However, in the other layers analyzed, the cover crops obtained higher availability of labile inorganic P. The systems using cover crops recovered 100% of the P fertilized in soybean.

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Soybean (Glycine max) is the world's most cultivated legume; currently, most of its varieties are Bt. Spodoptera spp. (Lepidoptera: Noctuidae) are important pests of soybean. An artificial neural network (ANN) is an artificial intelligence tool that can be used in the study of spatiotemporal dynamics of pest populations. Thus, this work aims to determine ANN to identify population regulation factors of Spodoptera spp. and predict its density in Bt soybean. For two years, the density of Spodoptera spp. caterpillars, predators, and parasitoids, climate data, and plant age was evaluated in commercial soybean fields. The selected ANN was the one with the weather data from 25 days before the pest's density evaluation. ANN forecasting and pest densities in soybean fields presented a correlation of 0.863. It was found that higher densities of the pest occurred in dry seasons, with less wind, higher atmospheric pressure and with increasing plant age. Pest density increased with the increase in temperature until this curve reached its maximum value. ANN forecasting and pest densities in soybean fields in different years, seasons, and stages of plant development were similar. Therefore, this ANN is promising to be implemented into integrated pest management programs in soybean fields.

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Soybean cultivation in tropical regions relies on symbioses with nitrogen-fixing Bradyrhizobium and plant growth-promoting bacteria (PGPBs), reducing environmental impacts of N fertilizers and pesticides. We evaluate the effects of soybean inoculation with different bacterial consortia combined with PGPBs or microbial secondary metabolites (MSMs) on rhizosoil chemistry, plant physiology, plant nutrition, grain yield, and rhizosphere microbial functions under field conditions over three growing seasons with four treatments: standard inoculation of Bradyrhizobium japonicum and Bradyrhizobium diazoefficiens consortium (SI); SI plus foliar spraying with Bacillus subtilis (SI + Bs); SI plus foliar spraying with Azospirillum brasilense (SI + Az); and SI plus seed application of MSMs enriched in lipo-chitooligosaccharides extracted from B. diazoefficiens and Rhizobium tropici (SI + MSM). Rhizosphere microbial composition, diversity, and function was assessed by metagenomics. The relationships between rhizosoil chemistry, plant nutrition, grain yield, and the abundance of microbial taxa and functions were determined by generalized joint attribute modeling. The bacterial consortia had the most significant impact on rhizosphere soil fertility, which in turn affected the bacterial community, plant physiology, nutrient availability, and production. Cluster analysis identified microbial groups and functions correlated with shifts in rhizosoil chemistry and plant nutrition. Bacterial consortia positively modulated specific genera and functional pathways involved in biosynthesis of plant secondary metabolites, amino acids, lipopolysaccharides, photosynthesis, bacterial secretion systems, and sulfur metabolism. The effects of the bacterial consortia on the soybean holobiont, particularly the rhizomicrobiome and rhizosoil fertility, highlight the importance of selecting appropriate consortia for desired outcomes. These findings have implications for microbial-based agricultural practices that enhance crop productivity, quality, and sustainability.

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PURPOSE: This study investigated the impact of four weeks of age-dependent detraining on army soldiers' cardiorespiratory fitness and maximal and explosive strength. METHODS: Fourteen volunteer tactical athletes participated, divided into two age groups (20 to 29 and 30 to 40 years). Before and after the detraining period, we assessed their anthropometric measurements (weight, height, body mass index, fat mass, and fat-free mass), cardiorespiratory fitness (maximal oxygen uptake [VO2max] and ventilatory thresholds [VT1 and VT2]), and kinematic properties during a single-leg counter-moving jump (CMJ) test for both the dominant and non-dominant legs. Two-way ANOVA followed by the Holm-Sidak post hoc test was used. RESULTS: The anthropometric and cardiovascular variables did not show significant differences between the groups. However, both groups exhibited a significantly reduced maximum time and speed at the VO2max. Furthermore, the flight time and maximum height during the CMJ significantly decreased in the non-dominant leg for both age groups. Notably, the dominant leg's concentric impulse (CI) significantly reduced during the CMJ, but this effect was observed only in the 30-40 age group. There were significant differences between the two age groups. CONCLUSIONS: Our findings suggest that four weeks of detraining negatively impacts aerobic fitness and muscular strength, independently of age. However, the dominant leg may be more susceptible to detraining effects in army soldiers aged 30-40. Furthermore, as a perspective, our results strongly suggest that a detraining period could affect successful missions (aerobic performance deterioration), as well as promote a muscle imbalance between the legs, which could encourage muscle injuries and endanger combat missions.

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Soybean [Glycine max (L.) Merr.] is one of the world's five major food crops, and Brazil produces the highest share at around 42%. Anthracnose caused by Colletotrichum is an important limiting factor to soybean production. In November 2013, anthracnose symptoms, characterized by brown irregular-shaped lesions on petioles, stems, and pods were observed in soybean fields (1% of incidence) in Vera, Mato Grosso State, Brazil. From the five plants gathered in the field, three leaves along with their corresponding petioles were meticulously chosen for the removal of symptomatic tissues. Sampling of these tissues involved carefully cutting a 0.5 × 0.5 cm fragment in the lesion area. The fragments were disinfected with 70% ethanol for 1 min, followed by 1% sodium hypochlorite for 2 min. Then the fragments were rinsed three times in sterile distilled water, placed on water-agar, and incubated at 25 °C for four days, in a 12/12 h photoperiod. Hyphal tips were transferred to potato dextrose agar (PDA) plates and incubated as previously described for seven days. A Colletotrichum sp. single-spore isolate (LFN0461) was selected, grown, preserved in filter paper, and stored at -80 °C. In 2023, it was reactivated for molecular characterization. On PDA, colony showed a rough-like mycelial growth, violaceous-black (front/reverse), with curved-shaped conidia 14.7 - 28.2 × 2.1 - 8.96 µm (average 18.4 × 4.7 µm). The DNA was extracted from 10-day-old mycelium using the cetyltrimethylammonium bromide (CTAB) method. The rDNA internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), histone (HIS3), and ß-tubulin 2 (TUB2) regions were amplified by polymerase chain reaction (PCR), using the primer pairs ITS-1F + ITS-4 (Gardes and Bruns 1993; White et al. 1990), GDF1 + GDR1 (Guerber et al. 2003), CYLH3F + CYLH3R (Crous et al. 2006), and Bt2A + Bt2B (Glass and Donaldson 1995), respectively. The sequences were deposited in the GenBank database (accession numbers: PP209207 - ITS; PP213392 - GAPDH; PP213393 - HIS3; MN688797 - TUB2). The reconstruction of the multilocus phylogenetic tree revealed that the LFN0461 isolate clustered with C. cholorophyti reference strain (IMI 103806) with 99.9% of Bayesian probability. Given the seed-borne nature of soybean anthracnose (Boufleur et al. 2021; Yang et al. 2013), pathogenicity tests were carried out by soybean seeds inoculation. Fifty seeds of NS6220 IPRO (Nidera) cultivar were inoculated by water restriction method, with LFN0461 colonies grown on PDA amended with mannitol (Machado et al. 2004), while 50 seeds were placed on PDA amended with mannitol as negative control. Soybean seeds remained in contact with the inoculum for 48 hours. Subsequently, seeds were sown in 2 L pots (n = 10) containing sterilized substrate, which were placed in a greenhouse at 25 ± 5 ºC. After 10 days, inoculated soybean seedlings exhibited characteristic necrotic lesions on cotyledons and hypocotyls, while negative control plants remained asymptomatic. Colletotrichum chlorophyti was successfully reisolated from the symptomatic tissues. Currently, C. chlorophyti has been reported to cause soybean anthracnose and infect seeds in the United States (Yang et al. 2013, 2012). Although this pathogen has not been reported since our first observation in 2013 in Brazil, many Colletotrichum isolates are misidentified due to reliance on morphology (Boufleur et al. 2021). To our knowledge, this study is the first report of C. chlorophyti causing soybean anthracnose in Brazil, joining a new group of emergent Colletotrichum spp. associated with this disease.

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BACKGROUND: Plant volatile organic compounds (VOCs) play a crucial role in mediating interactions between plants, herbivores and natural enemies. Among these VOCs, methyl salicylate and (E,E)-α-farnesene are emitted as herbivore-induced plant volatiles (HIPVs) by soybean plants in response to feeding by the brown stink bug Eushistus heros. These HIPVs function as synomones, influencing the foraging behaviour of the egg parasitoid, Telenomus podisi, the main natural enemy of E. heros, one of the major soybean pests in Brazil. RESULTS: Laboratory experiments showed that two soybean cultivars, BRS 7580 and BRS 7880, produced similar qualitative blends of HIPVs, with methyl salicylate, (E,E)-α-farnesene and (Z)-3-hexenyl acetate being produced by both cultivars. Soybean cultivar BRS 7580 produced a significant lower amount of HIPVs compared to BRS 7880 but this difference did not affect the attractiveness of the egg parasitoid Telenomus podisi. Field experiments using these two cultivars and synthetic applications of methyl salicylate and (E,E)-α-farnesene showed a substantial increase in egg parasitism in all treated areas. Parasitism rates ranged from 50% to 80% in areas where these HIPVs were deployed, compared to only 10% in untreated control areas. CONCLUSIONS: The egg parasitoid Telenomus podisi demonstrated an adept ability in recognising between HIPVs in soybean blends, even in the presence of significant quantitative differences. The results from the field experiment showed the potential of HIPVs in attracting natural enemies to specific target areas within fields. (E,E)-α-Farnesene showed an improved action during the later stages of soybean growth, notably at R6. In addition, this volatile attracted other families of natural enemies. © 2024 Society of Chemical Industry.

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Soybean is the main oilseed cultivated worldwide. Even though Brazil is the world's largest producer and exporter of soybean, its production is severely limited by biotic factors. Soil borne diseases are the most damaging biotic stressors since they significantly reduce yield and are challenging to manage. In this context, the present study aimed to evaluate the potential of a bacterial strain (Ag109) as a biocontrol agent for different soil pathogens (nematodes and fungi) of soybean. In addition, the genome of Ag109 was wholly sequenced and genes related to secondary metabolite production and plant growth promotion were mined. Ag109 showed nematode control in soybean and controlled 69 and 45% of the populations of Meloidogyne javanica and Pratylenchus brachyurus, respectively. Regarding antifungal activity, these strains showed activity against Macrophomia phaseolina, Rhizoctonia solani, and Sclerotinia sclerotiorum. For S. sclerotiorum, this strain increased the number of healthy plants and root dry mass compared to the control (with inoculation). Based on the average nucleotide identity and digital DNA-DNA hybridization, this strain was identified as Bacillus velezensis. Diverse clusters of specific genes related to secondary metabolite biosynthesis and root growth promotion were identified, highlighting the potential of this strain to be used as a multifunctional microbial inoculant that acts as a biological control agent while promoting plant growth in soybean.

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This study investigated the effect of AgNPs and AgNO3, at concentrations equivalent, on the production of primary and secondary metabolites on transgenic soybean plants through an NMR-based metabolomics. The plants were cultivated in a germination chamber following three different treatments: T0 (addition of water), T1 (addition of AgNPs), and T2 (addition of AgNO3). Physiological characteristics, anatomical analyses through microscopic structures, and metabolic profile studies were carried out to establish the effect of abiotic stress on these parameters in soybean plants. Analysis of the 1H NMR spectra revealed the presence of amino acids, organic acids, sugars, and polyphenols. The metabolic profiles of plants with AgNP and AgNO3 were qualitatively similar to the metabolic profile of the control group, suggesting that the application of silver does not affect secondary metabolites. From the PCA, it was possible to differentiate the three treatments applied, mainly based on the content of fatty acids, pinitol, choline, and betaine.

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We examined if carbohydrate (CHO) mouth rinse may reduce central fatigue and perceived exertion, thus improving maximal incremental test (MIT) performance. Nine recreational cyclists warmed up for 6 min before rinsing a carbohydrate (CHO) or placebo (PLA) solution in their mouth for 10 s in a double-blind, counterbalanced manner. Thereafter, they performed the MIT (25 W·min-1 increases until exhaustion) while cardiopulmonary and ratings of perceived exertion (RPE) responses were obtained. Pre- to post-MIT alterations in voluntary activation (VA) and peak twitch torque (Tw) were determined. Time-to-exhaustion (p = 0.24), peak power output (PPO; p = 0.45), and V̇O2MAX (p = 0.60) were comparable between conditions. Neither treatment main effect nor time-treatment interaction effect were observed in the first and second ventilatory threshold when expressed as absolute or relative V̇O2 (p = 0.78 and p = 0.96, respectively) and power output (p = 0.28 and p = 0.45, respectively) values, although with moderate-to-large effect sizes. RPE increased similarly throughout the tests and was comparable at the ventilatory thresholds (p = 0.56). Despite the time main effect revealing an MIT-induced central and peripheral fatigue as indicated by the reduced VA and Tw, CHO mouth rinse was ineffective in attenuating both fatigues. Hence, rinsing the mouth with CHO was ineffective in reducing central fatigue, lowering RPE, and improving MIT performance expressed as PPO and time-to-exhaustion. However, moderate-to-large effect sizes in power output values at VT1 and VT2 may suggest some beneficial CHO mouth rinse effects on these MIT outcomes.

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Traditional monitoring of asian soybean rust severity is a time- and labor-intensive task, as it requires visual assessments by skilled professionals in the field. Thus, the use of remote sensing and machine learning (ML) techniques in data processing has emerged as an approach that can increase efficiency in disease monitoring, enabling faster, more accurate and time- and labor-saving evaluations. The aims of the study were: (i) to identify the spectral signature of different levels of Asian soybean rust severity; (ii) to identify the most accurate machine learning algorithm for classifying disease severity levels; (iii) which spectral input provides the highest classification accuracy for the algorithms; (iv) to determine a sample size of leaves that guarantees the best accuracy for the algorithms. A field experiment was carried out in the 2022/2023 harvest in a randomized block design with a 6x3 factorial scheme (ML algorithms x severity levels) and four replications. Disease severity levels assessed were: healthy leaves, 25 % severity, and 50 % severity. Leaf hyperspectral analysis was carried out over a wide range from 350 to 2500 nm. From this analysis, 28 spectral bands were extracted, seeking to distinguish the spectral signature for each severity level with the least input dataset. Data was subjected to machine learning analysis using Artificial Neural Network (ANN), REPTree (DT) and J48 decision trees, Random Forest (RF), and Support Vector Machine (SVM) algorithms, as well as a traditional classification method (Logistic Regression - LR). Two different input datasets were tested for each algorithm: the full spectrum (ALL) provided by the sensor and the 28 spectral bands (SB). Tests with different sample sizes were also conducted to investigate the algorithms' ability to detect severity levels with a reduced sample size. Our findings indicate differences between the spectral curves for the severity levels assessed, which makes it possible to differentiate between healthy plants with low and high severity using hyperspectral sensing. SVM was the most accurate algorithm for classifying severity levels by using all the spectral information as input. This algorithm also provided high classification accuracy when using smaller leaf samples. This study reveals that hyperspectral sensing and the use of ML algorithms provide an accurate classification of different levels of Asian rust severity, and can be powerful tools for a more efficient disease monitoring process.

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In search for novel materials to replace noble metal-based electrocatalysts in electrochemical energy conversion and storage devices, special attention is given to a distinct class of materials, MAX phase that combines advantages of ceramic and metallic properties. Herein, Nb4AlC3 MAX phase is prepared by a solid-state mixing reaction and characterized morphologically and structurally by transmission and scanning electron microscopy with energy-dispersive X-ray spectroscopy, nitrogen-sorption, X-ray diffraction analysis, X-ray photoelectron and Raman spectroscopy. Electrochemical performance of Nb4AlC3 in terms of capacitance as well as for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) is evaluated in different electrolytes. The specific capacitance Cs of 66.4, 55.0, and 46.0 F g-1 at 5 mV s-1 is determined for acidic, neutral and alkaline medium, respectively. Continuous cycling reveals high capacitance retention in three electrolyte media; moreover, increase of capacitance is observed in acidic and neutral media. The electrochemical impedance spectroscopy showed a low charge transfer resistance of 64.76 Ω cm2 that resulted in better performance for HER in acidic medium (Tafel slope of 60 mV dec-1). In alkaline media, the charge storage value in the double layer is 360 mF cm-2 (0.7 V versus reversible hydrogen electrode) and the best ORR performance of the Nb4AlC3 is achieved in this medium (Tafel slope of 126 mV dec-1).

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Glyphosate hormesis, identified as a potential means to enhance crop yields, encounters practical constraints because it is typically assessed through foliar applications. The expression and extend of hormesis in this approach are influenced by unpredictable environmental conditions, highlighting the need to explore alternative glyphosate application methods, such as seed treatment. This study aimed to assess glyphosate hormesis on growth rates and biomass accumulation in seedlings soybean cultivars. Two dose-response experiments [doses from 0 to 2880 g acid equivalent (ae) ha-1], one via foliar and one via seed, were conducted on three soybean cultivars [one non-glyphosate-resistant (NGR) and two glyphosate-resistant (GR, one RR and one RR2)]. In a subsequent experiment, three safe glyphosate doses (0, 90 and 180 g ae ha-1) applied via seed were evaluated on four soybean cultivars (two RR and two RR2). For foliar applications, the range of glyphosate doses increasing growth rates and dry biomass by 12-28 % were 5.6-45 g ae ha-1 for the NGR cultivar, of 45-720 g ae ha-1 for RR and of 11.25-180 g ae ha-1 for RR2. In the seed treatment, biomass increases of 16-60 % occurred at 45-180 g ae ha-1 for the NGR and RR cultivars, and 90-360 g ae ha-1 for RR2. Glyphosate doses of 90 and 180 g ae ha-1, applied via seeds, provided greater growth and biomass accumulation for the RR and RR2 soybean cultivars. Both foliar and seed applications of glyphosate increased growth and biomass accumulation in soybean cultivars, with seed treatments showing greater and more consistent enhancements. These findings propose practical and viable alternative for harnessing glyphosate hormesis to facilitate the early development of soybeans and potentially enhance crop yield.

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Bt soybean cultivation is increasing worldwide. The Cry1Ac protein expressed in Bt soybean efficiently controls several lepidopteran pests. The stink bug, Piezodorus guildinii (Westwood), a major pest for soybean in the Americas, is not controlled by Bt crops, although possible sub-lethal effects may occur. Even if there were no negative effects for sting bug, ingesting toxins could affect its bio-controllers. We tested through ELISA detection if P. guildinii ingests Cry1Ac from Bt soybean and possible effects on its development, reproduction, survival, and feeding behavior. Biological traits were evaluated under controlled conditions of nymphs and adults feeding on pods of near-isogenic cultivars DM5958iPRO (Bt) and DM59i (non-Bt). Feeding behavior was recorded using an AC-DC electropenetrography (EPG) device. Results indicated that P. guildinii ingested the Cry1Ac protein; however, nymphal period and accumulated survival percentage did not differ between cultivars. Feeding on Bt soybean pods did not affect fecundity (i.e., number of egg masses and eggs/female) nor egg viability. Different feeding behaviors were only detected on the pathway phase (stylet penetration into plant tissue), which was more pronounced in the Bt cultivar. However, the total duration of the feeding activities on seeds was numerically higher (ca. 2X) on Bt plants compared to non-Bt. This is the first study to demonstrate that P. guildinii does ingest the Cry1Ac protein and excrete it without being absorbed, probably explaining the lack of direct adverse effects on its biological parameters. EPG could indicate that Bt soybean plants might be less palatable than non-Bt to red-banded stink bug.

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This study examines the relationship between physiological complexity, as measured by Approximate Entropy (ApEn) and Sample Entropy (SampEn), and fitness levels in female athletes. Our focus is on their association with maximal oxygen consumption (VO2,max). Our findings reveal a complex relationship between entropy metrics and fitness levels, indicating that higher fitness typically, though not invariably, correlates with greater entropy in physiological time series data; however, this is not consistent for all individuals. For Heart Rate (HR), entropy measures suggest stable patterns across fitness categories, while pulse oximetry (SpO2) data shows greater variability. For instance, the medium fitness group displayed an ApEn(HR) = 0.57±0.13 with a coefficient of variation (CV) of 22.17 and ApEn(SpO2) = 0.96±0.49 with a CV of 46.08%, compared to the excellent fitness group with ApEn(HR) = 0.60±0.09 with a CV of 15.19% and ApEn(SpO2) =0.85±0.42 with a CV of 49.46%, suggesting broader physiological responses among more fit individuals. The larger standard deviations and CVs for SpO2 entropy may indicate the body's proficient oxygen utilization at higher levels of physical demand. Our findings advocate for combining entropy metrics with wearable sensor technology for improved biomedical analysis and personalized healthcare.

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Plant development and productivity depend on interactions with soil microorganisms for nutrient availability, promotion of growth and protection against phytopathogens. Although the influence of the phenological stages of soybean crops and their environmental conditions on the soil bacterial communities have already been reported, no studies have focused on the influence of integrated agrosilvopastoral systems on bacterial consortia. In this study, we evaluated the influence of the phenological stages of soybean cultivated under conventional full sunlight (CFS) and integrated crop-livestock-forestry (ICLF) systems on bacterial communities in the rhizosphere and in bulk soil using high-throughput sequencing techniques. Proteobacteria, Actinobacteriota and Acidobacteriota were the most abundant phyla in both the rhizosphere and the bulk soil at all growth stages. The results support our hypotheses that the richness and diversity of soil bacterial communities are influenced by different cultivation systems, and that the structure of the bacterial communities in the rhizosphere and the bulk soil are modulated by the phenological stages of the soybean crop.

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Drug repurposing of widely prescribed patent-off and cheap drugs may provide affordable drugs for cancer treatment. Nevertheless, many preclinical studies of cancer drug repurposing candidates use in vitro drug concentrations too high to have clinical relevance. Hence, preclinical studies must use clinically achievable drug concentrations. In this work, several FDA-approved cancer drugs are analyzed regarding the correlation between the drug inhibitory concentrations 50% (IC50) tested in cancer cell lines and their corresponding peak serum concentration (Cmax) and area under the curve (AUC) reported in clinical studies of these drugs. We found that for most targeted cancer drugs, the AUC and not the Cmax is closest to the IC50; therefore, we suggest that the initial testing of candidate drugs for repurposing could select the AUC pharmacokinetic parameter and not the Cmax as the translated drug concentration for in vitro testing. Nevertheless, this is a suggestion only as experimental evidence does not exist to prove this concept. Studies on this issue are required to advance in cancer drug repurposing.

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Performance in endurance sports decreases with aging, which has been primarily attributed to cardiovascular and musculoskeletal aging; however, there is still no clear information on the factors that are most affected by aging. The aim of this study was to compare two groups of runners (< 50 and > 50 years of age) according to their absolute, weight-adjusted maximal oxygen uptake (V̇O2max), lower limb lean mass-adjusted V̇O2max, ventilatory threshold, and respiratory compensation point (RCP). A total of 78 male recreational long-distance runners were divided into Group 1 (38.12 ± 6.87 years) and Group 2 (57.55 ± 6.14 years). Participants were evaluated for body composition, V̇O2max, VT, and RCP. Group 1 showed higher absolute and body mass-adjusted V̇O2max (4.60 ± 0.57 l·min-1 and 61.95 ± 8.25 ml·kg-1·min-1, respectively) than Group 2 (3.77 ± 0.56 l·min-1 and 51.50 ± 10.22 ml·kg-1·min-1, respectively), indicating a significant difference (p < 0.001, d = - 1.46 and p < 0.001, d = - 1.16). Correspondingly, Group 1 showed a significantly higher lower limb lean mass-adjusted V̇O2max (251.72 ± 29.60 ml·kgLM-1·min-1) than Group 2 (226.36 ± 43.94 ml·kgLM-1·min-1) (p = 0.008, d = - 0.71). VT (%V̇O2max) (p = 0.19, d = 0.19) and RCP (%V̇O2max) (p = 0.24, d = 0.22) did not differ between the groups. These findings suggest that both variables that are limited by central or peripheral conditions are negatively affected by aging, but the magnitude of the effect is higher in variables limited by central conditions. These results contribute to our understanding of how aging affects master runners.

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The use of plant resistance acts by intervening in the herbivore-host relationship, through morphological, physical or chemical factors of the plant. This study evaluated the oviposition and foliar consumption of Chrysodeixis includens (Walker [1858]) in soybean genotypes, in free- and no-choice tests, correlating them with the factors, density and size of trichomes. The experiments were carried out in laboratory (25 ± 2 °C; RH= 70 ± 10%; photoperiod 14h) using five cultivars (BRS 391, BRS 6203 RR, BMX Valente RR, Tec Irga 6070 RR, BMX Icone Ipro) and two isolines (PELBR 10-6000 and PELBR 10-6049). The trichomes reported were filiform tectors and claviform multicellular glandular. The density of glandular trichomes, in stages V2 and V5, was higher on BRS 6203 RR and BRS 391, respectively. The higher density of glandular trichomes was observed in V5 and a higher density of tector trichomes in V2. The lowest densities and the smallest sizes of trichomes in V2 and V5 stages was observed on PELBR 10-6049. The size of tector trichomes and the number of eggs did not differ among the cultivars. Foliar consumption was lower for on BMX Icone Ipro and Tec Irga 6070 RR. Trichome density influences the consumption and oviposition behavior of C. includens.

O uso da resistência de plantas atua intervindo na relação herbívoro-hospedeiro, através de fatores morfológicos, físicos ou químicos da planta. O objetivo deste trabalho foi avaliar a oviposição e o consumo foliar de Chrysodeixis includens (Walker [1858]) em genótipos de soja, através de testes com e sem escolha, correlacionando-os com os fatores, densidade e tamanho de tricomas. Os experimentos foram realizados em laboratório (25 ± 2 °C; UR= 70 ± 10%; fotoperíodo 14h) utilizando cinco cultivares (BRS 391, BRS 6203 RR, BMX Valente RR, Tec Irga 6070 RR, BMX Icone Ipro) e duas linhagens (PELBR 10-6000 e PELBR 10-6049). Os tricomas encontrados foram tectores filiformes e glandulares multicelulares claviformes. A densidade de tricomas glandulares nos estágios V2 e V5, foi maior em BRS 6203 RR e BRS 391, respectivamente. A maior densidade de tricomas glandulares foi observada em V5 e a maior densidade de tricomas tectores em V2. As menores densidades e os menores tamanhos de tricomas nos estágios V2 e V5 foram observados em PELBR 10-6049. O tamanho de tricomas tectores e o número de ovos não diferiram entre as cultivares. O consumo foliar foi menor para BMX Icone Ipro e Tec Irga 6070 RR. A densidade de tricomas influência o comportamento de consumo e oviposição de C. includens.

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Introducción: La capacidad de resistencia física es uno de los indicadores del rendimiento profesional en el fútbol, no estando exceptos los profesionales del arbitraje, los cuales requieren entrenamientos especializados en función de sus aptitudes físicas; por lo cual, es útil conocer sus desempeños. Objetivo: determinar los parámetros reales de aptitud cardiorrespiratoria al esfuerzo máximo progresivo, de árbitros de fútbol de Pichincha. Métodos: se estudia a 25 árbitros hombres seleccionados intencionalmente, de la asociación de árbitros de fútbol profesional de Pichincha. Luego de un reconocimiento de salud previo, de realizó una prueba de esfuerzo progresivo sobre una banda sinfín, con un lector de consumo de oxígeno. Los árbitros tienen una experiencia media de 11 años, entrenan 3-4 días a la semana, y arbitran partidos oficiales 1-2 veces por semana. Resultados: el valor medio global de consumo máximo de oxígeno (VO2máx.) relativo de los árbitros evaluados en el presente estudio es: (= 52.00 ml·kg-1·min-1, similar al obtenido en otros estudios internacionales sobre la valoración de la capacidad física en árbitros, que describen unos valores relativos de vo2máx de 46-51 ml·kg-1·min-1 para hombres. Conclusiones: las competencias profesionales del arbitraje ecuatoriano son similares en la capacidad de resistencia que sus homólogos extranjeros. Se sugiere una implementación de contenidos del entrenamiento basados en mejorar la aptitud cardiorrespiratoria en el arbitraje, así como su control sistemático.

Introduction: Physical endurance capacity is one of the indicators of professional performance in soccer, not excepting referee professionals, who require specialized training based on their physical capabilities; Therefore, it is useful to know their performances. Objective: Determine the real parameters of cardiorespiratory fitness at maximum progressive effort, of soccer referees from Pichincha. Methods: 25 male referees intentionally selected from the Pichincha professional soccer referee association are studied. After a previous health examination, a progressive stress test was performed on a treadmill, with an oxygen consumption reader. Referees have an average experience of 11 years, train 3-4 days a week, and referee official matches 1-2 times a week. Results: The overall average value of relative maximum oxygen consumption (VO2max) of the referees evaluated in the present study is: (= 52.00 ml·kg-1·min-1, similar to that obtained in other international studies on the capacity physics assessment in referees, who describe relative vo2max values of 46-51 ml·kg-1·min-1 for men. Conclusions: the professional skills of Ecuadorian arbitration are similar in resistance capacity to their foreign counterparts. An implementation of training content based on improving cardiorespiratory fitness in refereeing, as well as its systematic control, is suggested.

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Soybean (Glycine max L.) is produced in over 70,000 ha in the Altillanura Region, eastern Colombia (Agronet 2023). From 2018 to 2020, foliar symptoms like green stem and foliar retention of soybean, which in Brazil can cause up to 100% soybean yield losses (Meyer et al. 2017), were observed in soybean fields in Colombia. During 2020, samples from symptomatic plants in reproductive stages (R1-R8) were collected from different commercial soybean fields in the Altillanura Region. Over 200 samples were processed, using an incubation method described in Coyne et al. (2014). Nematodes were recovered from photosynthetic leaf tissues and enlarged nodes/buds with population densities ranging from 13 to 132 and 36 to 936 nematodes/10g, respectively. Adult females were morphologically and molecularly characterized as Aphelenchoides pseudobesseyi (Oliveira et al. 2019; Subbotin et al. 2020). Female body length (n = 20) ranged from 653.3 to 806.3 µm (mean = 723 µm ± 52.7), stylet length from 11.0 to 12.3 µm (11.8 µm ± 0.3), body diameter from 14.8 to 17.9 µm (16.3 µm ± 1.1), post-uterine sac length from 38.7 to 51.9 µm (44.6 µm ± 5.1), vulva to anus from 145.5 to 223.2 µm (172.2 µm ± 22.4), and 26% of the vulva-anus distance. Genomic DNA was extracted (QIAGEN DNeasy® Blood & Tissue kit) from a pool of nematodes. The D2A/D3B (Tenente et al. 2004) primers were used to amplify and sequence the D2/D3 expansion region of the 28S rRNA gene. PCR product (~759 bp) was purified, sequenced, deposited in GenBank (OQ930285), and compared to previously deposited sequences (e.g., KX356756, KY510840, KY510839, KY510841, KT692694, KY510842, MH187565) by means of the BLAST algorithm. Similarly, 988F and 18SR-Burs (De Jesus et al. 2016) primers were used to amplify and sequence the near full-length 18S RNA gene (SSU). PCR product was purified, sequenced, deposited in GenBank (OQ954344), and compared to previously deposited sequences (e.g., KT454962, KT943534, KT943535, KY510835, KY510836, KY510837, KY510838, MH187565). Phylogenetic Bayesian analysis (Ronquist et al. 2012) of the of the D2/D3 and 18S regions placed this nematode from Colombia in the A. pseudobesseyi clade (PP = 100). To fulfill a modified Koch's postulates, the A. pseudobesseyi population described above was used in a greenhouse assay. In total, 120 soybean plants (cv. Flor Blanca) were infected with 200 A. pseudobesseyi (females + males)/plant. Briefly, at cotyledon stage (VC), 50 µl aliquot containing 50 A. pseudobesseyi was delivered onto each cotyledon and unifoliolate leaves (200 nematodes/plant). Sterile water was delivered to 80 plants which served as control. Plants were kept in the greenhouse at approximately 25°C and covered with clear plastic bag for 72 h to maintain over 90% relative humidity. After 15, 30, 45, and 60 days, soybean plants (n = 20) were processed, A. pseudobesseyi quantified, and the average reproduction factor (final population/initial population) was 0.1, 2.9, 14.0, and 1.8, respectively. Infected plants showed symptoms of blistering leaves with malformation (midrib vein twist), and A. pseudobesseyi was not observed in control plants. To our knowledge, this is the first report of A. pseudobesseyi parasitizing soybean buds and leaves in Colombia. Soybean is an important commodity for the Altillanura Region, and it is important to monitor the risk posed by this nematode. Furthermore, a better understanding of the nematode-host interaction and epidemiology in Colombia soybean producing regions is needed.