The variation of sunlight throughout the year, caused by the tilt of the Earth’s axis and its spherical shape, influences surface heating, temperatures, atmospheric currents, and rainfall distribution. Solar energy, being clean and sustainable, has many applications. Using it efficiently requires understanding its temporal distribution. The daily accumulation of solar irradiation follows a sigmoidal pattern, which can be described by non-linear regression models. These models offer practical and innovative interpretations for renewable energy projects, filling a gap in the scientific literature. This study was conducted to evaluate the suitability of the Logistic, Gompertz, and Von Bertalanffy non-linear regression models to describe the accumulation of daily global solar irradiation (kJ m-²). Data on global irradiation accumulated throughout the day at ground level, during the equinoxes and solstices in Belo Horizonte/MG, were obtained from the Brazilian National Institute of Meteorology (INMET) through the Annual Historical Data for the period 2018 to 2022. The Logistic and Gompertz models met the evaluated statistical assumptions, unlike the Von Bertalanffy model. The Logistic model achieved a better fit for the equinox and winter solstice data, while the Gompertz model was more suitable for the summer solstice data. The asymptotic estimates (α) of the Logistic model were statistically equivalent for the equinoxes but not for the solstices. The β parameter (abscissa of the inflection point) was statistically equivalent for the solstices and the spring equinox.
Seed dormancy is a constraint in the propagation of forage peanut, limiting large-scale production. Tissue culture techniques, particularly embryo rescue, offer a promising alternative for breaking dormancy and ensuring uniform seedling establishment. This study was developed in order to evaluate the effect of gibberellic acid (GA₃) on embryo germination, with the objective of establishing an efficient protocol for in vitro embryo cultivation. Embryos extracted from four seed lots were cultured on Murashige and Skoog (MS) medium supplemented with five concentrations of GA₃ (0, 10, 20, 40, and 80 mg L-1). Seeds were surface-sterilized with 70% ethanol followed by 2% sodium hypochlorite and rinsed with deionized water. Embryos were excised using a sterile scalpel in a laminar flow hood and cultured as explants for regeneration. After 21 days, germination rate, seedling growth parameters, and photosynthetic pigment contents were assessed. Statistical analyses included analysis of variance (ANOVA) and polynomial regression, with treatment effects compared using Tukey’s test (p ≤ 0.05). A quadratic response was confirmed for most parameters, underscoring the importance of dose optimization. Moderate GA₃ concentrations (40 mg L-1) significantly improved embryo germination compared to the control, whereas higher concentrations (80 mg L-1) negatively impacted chlorophyll content and optimal shoot and root development. GA₃ application during in vitro culture influenced seedling development, promoting shoot elongation and altering pigment composition. In vitro culture proved to be an effective approach for assessing the physiological response of Arachis pintoi seedlings to varying gibberellin levels, contributing to a better understanding of dormancy-breaking mechanisms in this species.
Population dynamics and spatial use by didelphid marsupials are fundamental for understanding gene flow, community structure, and ecosystem functioning, as these animals play key roles in seed dispersal, food web dynamics, metapopulation processes, and disease ecology. However, available data often show contradictory patterns across study areas. This study aimed to describe and analyze the home range of Didelphis albiventris in a broad landscape within the ecotonal region between the Atlantic Forest and Cerrado. Additionally, we examined abundance, sex ratio, reproductive females, residence time or movement between fragments, and their relationships with body mass. Sampling was conducted over 14 months using Tomahawk, Sherman, and pitfall traps in a capture–mark–recapture design. Distances covered ranged from 0.20 to 4.16 km. Home ranges, based on three to six recaptures, varied from 2.10 to 8.49 km in perimeter and 0.0007 to 1.17 km² in area. We captured 146 individuals (95 females and 51 males) with 126 recaptures. The mean litter size was six. The overall sex ratio favored females across all sampled fragments. The average residence time in fragments was 19.33 days. Regression analyses showed no significant relationship between body mass and displacement or permanence. Home ranges were larger than those previously reported. Females were more numerous and exhibited longer and more frequent movements between small forest fragments. Litter size was smaller than that reported for other regions of southeastern Brazil. Overall, D. albiventris in this region showed high abundance, a female-biased population, and expanded spatial use.
Late-season diseases (LSDs) are among the most significant biotic factors limiting soybean yield. Exploring alternative strategies for LSD management yields social, environmental, and economic benefits. This study aimed to evaluate the effectiveness of carboxamide-based fungicide applications in controlling soybean LSDs. The experiment was conducted in Pinhalzinho, São Paulo, Brazil, using a randomized complete block design (RCBD) with five treatments and four replicates, totaling 20 experimental units. Treatments included four fungicide management strategies involving carboxamides and one untreated control. Fungicide applications began 27 days after sowing (DAS) and were repeated every 15 days following disease detection. Evaluated variables included disease severity, area under the disease progress curve (AUDPC), number of pods per plant, number of seeds per pod, grain yield (kg ha⁻¹), and thousand-grain weight. Data were subjected to analysis of variance (ANOVA) and treatment means were compared using Tukey’s test (p < 0.05). Results showed that treatments 2 and 4 were most effective in reducing the progression of target spot and brown spot, respectively. In contrast, treatment 1 exhibited the highest severity of leaf blight. Treatment 2 achieved the highest yield (4974.12 kg ha⁻¹), though yield differences among treatments were not statistically significant. Thousand-grain weight did not differ significantly across treatments, with treatment 3 showing the highest average (185.62 g). Overall, the use of carboxamide-based fungicides contributed to reducing LSD severity and maintaining grain yield, indicating their viability as a tool within integrated disease management strategies.
Sharing agricultural areas with genetically modified corn, conventional corn is subject to drift of glyphosate applied to adjacent areas, requiring evaluation of consequences from this intoxication. Thus, this work was developed in order to evaluate the sensitivity of two conventional corn hybrids to subdoses of glyphosate herbicide. Three similar experiments were conducted in a greenhouse, between November 2023 and May 2024. The first and second experiments assessed the Biomatrix BM3051 conventional hybrid corn; the third experiment evaluated the Semeali XB8018 hybrid corn. All experiments used five subdoses of the glyphosate herbicide, at a highest dose applied of 144 g ha−1. Plants were sprayed at a vegetative stage of three to four leaves. Qualitative (description of anatomical and morphological changes) and quantitative symptoms were evaluated using a visual scale of phytotoxicity and dry matter mass. Glyphosate doses equal to or greater than 36 g ha−1 led to significant intoxication of corn plants, possibly reducing dry matter. Biomatrix BM3051 had greater sensitivity to glyphosate intoxication compared with Semeali XB8018 corn. Most common phytotoxic symptoms observed included (in increasing order of intensity): slight reduction in size, yellowish streaks, wrinkling of the leaf blade, chlorosis or bleaching of young leaves, purplish leaf blade, curled leaves similar to drought damage, excessive formation of adventitious roots, necrosis of older leaves, generalized necrosis, tillering and meristematic damage. For the hybrid Semeali XB8018, glyphosate-induced hormetic effect occurred at doses below 36 g ha−1. Considering 1,440 g ha−1 of glyphosate as a maximum dose, the 36 g ha−1 subdose equals 2.5%. Thus, the severe toxic symptoms observed in the field may result from improper applications rather than from glyphosate drift into adjacent areas.
Wildfire occurrences annually affect different vegetation regions, generating environmental, economic, and social impacts. The municipality of Rio de Contas, located in Chapada Diamantina, Bahia, constitutes one of these vulnerable areas. In this context, the use of geotechnologies such as remote sensing is essential for monitoring and analyzing affected territories. This study was developed to evaluate wildfire occurrences on a spatiotemporal scale in Rio de Contas from 2010 to 2024, using satellite imagery and geoprocessing techniques. Data on fire outbreaks were obtained from the Wildfire Program of the National Institute for Space Research (INPE), whereas burned area data were extracted from NASA’s Reverb platform and the University of Maryland. Meteorological information was provided by the National Institute of Meteorology (INMET). Analyses were performed on QGIS, applying Kernel density estimation. Of the 101 wildfire outbreaks identified, 48.5% occurred within conservation units. Its highest incidence was recorded in September, with an average burned area of 394.18 ha, associated with low rainfall rates. Spatial analysis indicated a concentration of fire outbreaks in areas above 1000 meters in altitude, predominantly in grassland savanna. Thus, the most prone periods to wildfires and their association with local climatic variables were identified. These findings highlight the relevance of geotechnologies in environmental planning and management, providing support for wildfire prevention and mitigation strategies.
Adulteration of spices may negatively impact food quality and safety. The addition of starch is a fraud unlikely to be detected by consumers. Therefore, this study was developed in order to quantify, by optical microscopy, the presence of corn and wheat starch in ground black pepper and to validate equations for estimating starch percentage to identify adulteration. Black pepper grain samples were ground and intentionally adulterated with 3%, 5%, 10%, 15%, and 20% corn starch and wheat flour, separately, and subsequently analyzed by optical microscopy. A linear regression model was adjusted to estimate the percentage of adulterant starch. A spreadsheet was developed to calculate the estimated mean starch percentage and its lower and upper limits. The model was validated by means of a blind test (samples adulterated at unknown levels to the analyst). Additionally, three commercial samples and three suppliers were evaluated. Structural differences were observed between corn and wheat starch granules, enabling their identification and quantification. The blind test confirmed the effectiveness of the method in identifying and counting starch granules, validated the adjusted mathematical model, and enabled satisfactory quantification of the adulteration percentage, reinforcing the reliability of the results. Wheat starch was detected in all three commercial samples and in two of the three supplier samples. Therefore, optical microscopy may be highlighted as a practical tool for the food industry, contributing significantly to fraud detection, quality assurance, and authentication of spices.
This study was developed to evaluate the effects of inoculating beneficial microorganisms in the second-crop corn culture, with an emphasis on the correlations between morphological and productive traits. The experiment was carried out in the municipality of Mineiros, Goi & aacute;s state, Brazil. The experimental design included seed and foliar treatments, involving Trichoderma asperellum, Bacillus subtilis, and a standard chemical treatment. Statistical analyses were performed using R software. It was demonstrated that inoculation promoted significant changes in root development, resulting in greater accumulation of aboveground biomass and gains in productive potential. Overall, the microorganisms evaluated, particularly T. asperellum and B. subtilis, showed potential for optimizing early growth, physiological efficiency, and productivity in second-crop corn, in addition to contributing to reducing dependence on mineral fertilizers. Therefore, the use of the TS3 treatment is technically recommended as a viable alternative for maximizing corn productivity, maintaining a balance between yield components and plant structural characteristics. However, it is emphasized that further research should be conducted in different harvests, soil and climate conditions, and management systems to validate and refine these recommendations, ensuring greater robustness and applicability of the results obtained.
Coffee farming is crucial for Brazil, the world leader in coffee production and export. Strategies like the "safra zero”, which involve practices such as skeleton pruning, have been adopted to rejuvenate coffee plants and optimize production in alternate years. This contributes to reducing costs and labor demand. Faced with the environmental and economic challenges of coffee cultivation, bio-inputs stand out as a sustainable alternative in crop management, especially during vegetative recovery phases. Therefore, this study aimed to evaluate the effects of applying bio-inputs to coffee plants subjected to skeleton pruning. The experiment was conducted using a randomized block design, in split plots, with eight treatments: five bacterial strains (UNIFENAS 100-94, Azospirillum brasilense, Pseudomonas fluorescens, Bacillus megaterium, and Bacillus subtilis), organized into six combinations, plus a treatment with A. brasilense isolated and a control, with four replicates. Applications occurred in March, April, August, and September. Plant height, plagiotropic branch length, and the number of buds were evaluated every 30 days. At the end, soil and leaf chemical analyses were also performed. Plant height and branch length did not differ significantly between treatments, but the number of buds showed a difference at 210 days when the UNIFENAS 100-94 and P. fluorescens strains were used. All analyzed variables evolved over time. Nutrient levels increased with the use of bio-inputs. It is concluded that these inputs show potential in the post-pruning management of coffee plants.
The use of biostimulants in coffee cultivation stands out as a sustainable option for agricultural efficiency, not only in terms of productivity but also in phytosanitary management. This work was developed in order to evaluate the effect of a freshwater algae extract, based on Chlorella sp. and enriched with Azospirillum sp., on the growth, yield, and beverage quality of Arabica coffee. The experiment was conducted at the IFSULDEMINAS Campus Inconfidentes in a randomized block design with eight treatments and three replications, at different phenological stages. Growth, yield, phytosanitary, and coffee quality variables were evaluated. Data were subjected to analysis of variance (ANOVA), principal component analysis, and a similarity network, in which correlations among data within a set were analyzed, enabling a more illustrative visualization of the relationships among variables. No significant differences were observed among the analyzed parameters, a result that may be explained by the doses used, which opens possibilities for future research. It is concluded that the application of the freshwater algae-based biostimulant at various phenological stages did not influence the growth or yield of Arabica coffee.
Brazilian agricultural production is often threatened by phytopathogenic bacteria, resulting in significant economic losses. Difficult to control and favored by the country's climatic conditions, bacterial wilt, caused by Ralstonia solanacearum and soft rot, by Pectobacterium carotovorum, are major diseases that affect a wide range of hosts. As an alternative control strategy, this study was developed to evaluate the chemical composition and antimicrobial activity of essential oils from Elionurus latiflorus (Brazilian lemongrass) and Citrus aurantium (bitter orange). The main components identified were citral (65.38 %) in E. latiflorus and limonene (94.71 %) in C. aurantium. The antimicrobial activity of the essential oils was assessed through disk diffusion assays, using concentrations of 1, 3, 5, 7, 10, and 15 mu L for E. latiflorus oil and 1, 3, 5, 7, 10, 15, 20, and 30 mu L for C. aurantium oil. E. latiflorus oil had strong antimicrobial effects against both bacteria. At 15 mu L, inhibition rates reached 86.46 % for R. solanacearum and 88.90 % for P. carotovorum. In contrast, C. aurantium oil had no inhibitory activity against the tested bacteria. These findings suggest that E. latiflorus essential oil may represent a natural, ecological, and efficient alternative for management of phytopathogenic bacteria.
This study aimed to propose and validate alternative management strategies to increase the productivity of white oat and wheat through the evaluation of agronomic components. Field experiments were conducted during the 2022 and 2023 fall/winter seasons in a randomized block design with three replicates, structured in four phases. Phases 1 and 2 compared the performance of white oat genotypes (URS Brava, IDR Artemis, URS Corona, and URS Taura). Phase 3 evaluated 15 treatments in white oat, combining fungal control agents, plant growth-promoting bacteria (e.g., Bacillus spp., Azospirillum brasilense, Pseudomonas fluorescens), phytohormones (e.g., indoleacetic acid), and fungicides. Phase 4 tested eight similar treatments in wheat. Standard sowing density, fertilization, and crop management practices were followed. Phytosanitary treatments were applied with a CO2-pressurized sprayer. Each phase was analyzed separately using ANOVA, with significance assessed via the F test (5% level), and means compared using Duncan’s test. In Phases 1 and 2, genotype significantly affected most variables, except grains per panicle (2022–2023) and panicle insertion height (2023). In Phases 3 and 4, fungal and growth promoter treatments significantly affected all evaluated variables in both species. Among the oat cultivars, IDR Artemis showed the highest yield in years with low lodging probability, while URS Corona exhibited lower lodging and high grain mass under lodging-prone conditions. Management alternatives influenced agronomic traits in both crops, though no significant effects were observed on final grain yield. These findings highlight the potential of genotype selection and integrated management to optimize oat and wheat performance.
Esmeralda zoysiagrass is the most widely marketed among turfgrass species; however, the soil’s chemical and physical factors can interfere with its development. Thus, it is essential to seek alternatives to mitigate these effects, and the combined use of liming and soil aeration may be an option. This study aimed to evaluate the impact of soil aeration combined with liming on Esmeralda grass. The experiment was conducted from November 14, 2018, to May 30, 2019, in a 363 m² experimental area divided into 30 plots. A randomized block design was used, consisting of five treatments with six replications: T1 – without liming and without aeration; T2 – without liming and with aeration; T3 – with liming and without aeration; T4 – with liming and aeration after liming; and T5 – with liming and aeration before liming. The following parameters were evaluated: soil plant analysis development meter (SPAD); height; dry mass of clippings; root length; dry mass of roots + rhizomes + stolons; and traction resistance. The best results were obtained from treatments combining liming with solid tine aeration (T4 and T5), demonstrating that this practice can be an excellent management strategy for the development of Esmeralda grass in sports fields.
Bacterial biopolymers are biodegradable substances and sustainable alternatives to conventional polymers. Thus, they have been gaining prominence as sustainable alternatives to petroleum-derived polymers, promoting research aimed at optimizing their production and application in various industrial sectors. In this context, this study aims to select rhizobacteria from the Caatinga with the potential to synthesize exopolysaccharides (EPS) and define the optimal conditions for their production. Bacterial suspensions were inoculated on sterile filter paper discs on culture medium inducing EPS production. EPS production was determined by the formation of a mucoid layer and confirmed in the presence of absolute ethanol. The isolates that accumulated the highest amount of EPS were subjected to tests based on the Rotational Central Composite Design (RCCD), varying pH, temperature, and glucose as a carbon source. EPS recovery was evaluated in two treatments: static fermentation and under constant agitation. Among the 15 isolates selected, PH9.1 had the best performance in assay 13 (pH 7.0; temperature 38.5°C; glucose 1%), with a mucoid layer diameter of 2.15 cm, higher than the others. Moreover, static fermentation resulted in a higher yield of fresh (0.64 g) and dry (0.42 g) mass, standing out as the most efficient condition, which reinforces the biotechnological potential of Caatinga rhizobacteria for sustainable EPS production and boosts new industrial applications.
Brazilian agricultural production is constantly harmed by the action of phytopathogenic bacteria, bringing economic damage to crops. Difficult to control and favored by the country's climatic conditions, "bacterial wilt" caused by Ralstonia solanacearum and "soft rot" by Erwinia carotovora are bacterial diseases that affect a wide range of hosts. As an alternative form of control, this study evaluated the inhibitory effect of the essential oils of Brazilian lemongrass (Elionurus latiflorus) and bitter orange (Citrus aurantium L.) rich in citral and limonene. Respectively, in the control of the phytopathogenic bacteria R. solanacearum and E. carotovora. The antimicrobial effect of essential oils was evaluated by means of disk diffusion tests, at doses of 1, 3, 5, 7, 10 and 15 μL for E. latiflorus oil and 1, 3, 5, 7, 10, 15, 20 and 30 μL for C. aurantium. The results showed that the essential oil of E. latiflorus showed an antimicrobial effect against both bacteria. At the dose of 15 μL, there was inhibition of 86.46 and 88.90% for the bacteria R. solanacearum and E. carotovora, respectively. The essential oil of C. aurantium showed no inhibition against any of the bacteria tested. The results indicate that the essential oil of E. latiflorus can be a natural, ecological and efficient alternative in the control of phytopathogenic bacteria.
Adjustments in the planting density of the Tumbeta variety under an irrigated system directly influence vegetative growth, resource use efficiency, and rice productivity. Defining an appropriate density maximizes crop yield. The objective of this study was to evaluate the effect of plant density on the agronomic performance of the Tumbeta rice cultivar under an irrigation system. The experiment was conducted during the 2022/2023 season at the Chókwè Agricultural Station, Gaza province, Mozambique, using a randomized complete block design (RCBD), with 10 treatments and three replications, totaling 30 plots. The treatments used were different transplant densities. The transplant densities ranged from 1 to 10 seedlings per hole. The variables analyzed were grain yield and number of panicles m⁻². The analysis of variance (ANOVA) revealed a significant effect of plant density on grain yield and the number of panicles m⁻². The highest grain yields were observed at densities of 4, 5, 6, and 7 plants per hole, with averages of 9.7, 9.4, 9, and 9 t ha⁻¹, respectively. For the number of panicles m⁻², the best density was 4 plants per hole, with 379 panicles m⁻². It is important to highlight that the plant density per hole has a direct impact on grain yield and the number of panicles m⁻² of the Tumbeta rice cultivar.
Glyphosate may be an alternative to mechanical mowing management, which may reduce turfgrass growth without harming the development of plant, and associated with the use of the correct cultivation base, it may benefits the plant. The objective of this study was to evaluate the use of glyphosate as a growth regulator in Bermuda grass, in different cultivation bases. The hybrid Bermuda grass ‘Tifway 419’ carpets were planted in 8.46 L containers with different substrates and, after 60 days, the first application of glyphosate was performed, forming a 5 x 4 factorial scheme (substrates x glyphosate doses) with three replicates. The cultivation bases were: B1 - soil, B2 - sand, B3 - soil + sand (1:1), B4 - soil + sand + organic compost (1:1:1) and B5 - organic compost + sand (1:1) and glyphosate doses: 0, 200, 400 and 600 g a.i. (active ingredient) ha-1. Chemical analyses of the substrates, photosynthetic pigments, fresh and dry mass and leaf macronutrients were performed. Glyphosate has great potential to be used as a growth regulator in Bermuda grass Tifway 419, as there was an effect of the herbicide doses on lawn development, and the dose of 400 g a.i. ha-1 provided reduction in fresh and dry mass without major changes in macronutrients and photosynthetic pigments, mainly when grown in B4.
This study was developed in order to examinate the combined effects of drought stress and integrated fertilizer management on maize yield and physiological characteristics in Iran's Bam and Fahraj regions. The experiment used a split-plot design with randomized complete blocks in three replications. Drought stress treatments were applied at three levels: no stress (-0.3 MPa), mild drought stress (-0.7 MPa), and severe drought stress (-1.1 MPa). Six fertilizer treatments were evaluated: no fertilizer, chemical fertilizer (300 kg N ha-1 + 150 kg P2O5 ha-1), phosphate biofertilizer, nitrogen biofertilizer, vermicompost (5 t ha-1), and integrated fertilizer management, combining 50 % chemical fertilizer with both biofertilizers and vermicompost. Integrated fertilizer management under optimal irrigation conditions had the highest impact on crop performance. Grain yield in Bam region increased from 5640.6 kg ha-1 under no stress conditions to 12341.2 kg ha-1 with integrated fertilizer treatment; and in Fahraj region from 4140 kg ha-1 to 10840.6 kg ha-1. The harvest index under no stress and integrated fertilizer treatment conditions reached the highest levels in Bam (45.94 %) and Fahraj (44.21 %). With increasing drought stress intensity, the harvest index decreased significantly, reaching 27.61 % in Bam under severe drought stress conditions. Therefore, integrated fertilizer management is an effective strategy for enhancing drought tolerance and improving maize performance in arid regions. The combination of chemical and biological fertilizers successfully mitigated the negative effects of drought stress and improved crop production efficiency.
It is necessary to search for solutions to control weeds, focusing on pre-emergent herbicides. Pyroxasulfone + flumioxazin is believed to be effective in controlling weeds in soybean, as well as other pre-emergent herbicides used in this crop. This study was developed in order to evaluate the effectiveness of the pre-formulated mixture pyroxasulfone + flumioxazin, for application in pre-emergence of soybean. Experiment was conducted in two trials in the 2020-2021 growing season. The treatments consisted of non-treated control, pyroxasulfone + flumioxazin (90 + 60 g ai ha-1), imazethapyr + flumioxazin (100 g ae ha-1 + 50 g ai ha-1), diclosulam (29.4 g ai ha-1), sulfentrazone + diuron (175 + 350 g ai ha-1) and s-metolachlor (1,440 g ai ha-1). Trial 1 was infested with Digitaria insularis (sourgrass), Ipomoea spp. (morning glory), Urochloa plantaginea (alexandergrass), and Amaranthus hybridus (smooth pigweed). Trial 2 was infested with sourgrass, morning glory, other grasses, and other broadleaves. Weed control, soybean injury and yield were evaluated. Pyroxasulfone + flumioxazin stood out, which was the only herbicide among the best in all evaluations, demonstrating its broad spectrum of action. Also highlighted are the other formulated premixes, imazethapyr + flumioxazin and sulfentrazone + diuron. Diclosulam was almost always among the most effective in controlling broadleaves, but with the worst performance in controlling grasses; the opposite was observed for s-metolachlor. Herbicides are effective in controlling weeds, with emphasis on pyroxasulfone + flumioxazin, imazethapyr + flumioxazin and sulfentrazone + diuron, effective in controlling sourgrass, smooth pigweed, morning glory, alexandergrass, among others.
