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The weeds if not properly controlled have great ability to settle in agricultural systems, affecting crop production. The objective of this work was to determine the interference and level of economic damage in different density of crop. The treatments were composed of canola hybrids (Hyola 50, Hyola 76, Hyola 433, Hyola 571 CL, Hyola 575 CL and Diamond) and twelve infestation turnip density in crop. The variables evaluated to estimate the competitiveness of the hybrids were plant density, leaf area, soil cover and dry mass of the turnip. Grain yield, canola price, herbicide efficiency, and control cost were used to determine the weed's level of economic damage on the crop. The canola hybrids Hyola 575 CL, Hyola 50, Hyola 76 and Hyola 571 CL are more competitive with turnip. The values of economic damage levels range from 2.86 to 5.95, 2.43 to 5.05, 2.22 to 5.43 and 2.99 to 6.22 turnip plants m-2 for hybrids Hyola 50, Hyola 76, Hyola 571 CL and Hyola 575 CL, respectively, as a function of simulated variables. The increased grain yield, canola price, herbicide efficiency and lower control costs reduce the level of economic damage, justifying the adoption of control.

Modern agriculture is threatened by the possibility of nutrient losses, largely attributable the presence of competing weeds in these spaces. The challenge is to manage these weeds efficiently with...

Keratinous residues are generated in large quantities in industrial processes and because of this they are difficult to manage because the presence of keratin. Keratinases are emerging as promising alternatives in technological processes. The objective of this work was to determine the potential of pretreatment of agro-industrial residues using an ultrasonic probe, and to evaluate activity enhancement strategies by analyzing the behavior of enzymatic activity of keratinases exposed to various reaction systems as well as to enzymatic concentration. We tested the application of enzymatic extracts in the degradation of keratinous residues. Submerged fermentation was performed with swine hair pretreated with and without ultrasonic probe. The enzymatic extracts were exposed to reaction systems and the enzymatic concentration technique to measure the increments of enzymatic activity. We found that the ultrasonic probe increased reaction rates, enabling higher enzyme production in shorter time periods. The ultrasonic probe reached 38.4% of relative activity and the enzyme concentration, increased the enzymatic activity in 53.5%. We observed potential degradation of chicken feathers with homemade enzyme extracts. Taken together, our findings suggest that the results obtained in this work are promising, despite the fact that the data in this area are scarce.

A planta medicinal Ruta graveolens L. (RG), popularmente conhecida como arruda, já foi sugerida na literatura com potencial para o desenvolvimento de medicamentos para o tratamento de demência e da doença de Alzheimer. O objetivo deste trabalho foi investigar os efeitos da administração aguda do óleo essencial de RG (100 mg/kg) sobre a memória de curta e longa duração e verificar a reversão da amnésia causada pela escopolamina em camundongos machos. Foram utilizados os testes de campo aberto, esquiva inibitória, labirinto aquático de Morris e avaliada a inibição da enzima acetilcolinesterase cerebral. Os resultados mostraram que uma única administração do óleo essencial de RG não alterou a atividade locomotora no teste de campo aberto, facilitou a aquisição de uma memória de longa duração na tarefa de esquiva inibitória, porém não preveniu a amnésia causada pela escopolamina. O óleo essencial de RG não apresentou efeitos sobre a memória de curta duração nem na inibição da acetilcolinesterase no córtex pré-frontal, hipocampo e estriado. No labirinto aquático de Morris não foram observadas alterações em nenhum dos tratamentos. Com base nos resultados obtidos, podemos concluir que o óleo essencial de RG facilitou a aquisição de uma memória aversiva de longa duração.

A gradativa expansão econômica, acelerada urbanização e contínuas melhorias dos padrões de vida da sociedade têm resultado no crescimento da geração per capita de resíduos sólidos urbanos, principalmente em países em desenvolvimento, como o Brasil. O referido parâmetro e a composição gravimétrica são importantes para o planejamento adequado do sistema de gerenciamento destes resíduos, porém, são altamente variáveis conforme as características de cada população e localidade. Sendo assim, este estudo teve por objetivo determinar a composição gravimétrica dos resíduos sólidos urbanos que são destinados ao aterro sanitário, localizado no Município de Palmeira das Missões, Rio Grande do Sul, Brasil, e estimar a geração per capita de resíduos de cada município atendido pelo aterro, bem como traçar comparativos com parâmetros socioeconômicos, e entre outras regiões do país e do mundo. A composição gravimétrica revelou que 41,8% dos resíduos sólidos urbanos é composto por resíduo orgânico, correspondendo a uma parcela semelhante à média da Região Sul e da nacional. Já os resíduos recicláveis representam 58,2% do total, diferenciando-se da parcela média das regiões brasileiras e de outros países. Verificou-se que, dos 27 municípios atendidos pelo aterro, 7,7% apresentam geração per capita de resíduos sólidos urbanos acima da média da Região Sul, e em 37% não há coleta seletiva. Referente aos fatores, número de habitantes e PIB per capita, nenhum se correlacionou significativamente com a geração per capita destes resíduos.

A influência da temperatura nos organismos é um dos aspectos essenciais para a regulação e manutenção da vida. Ao longo do tempo geológico a temperatura na Terra oscilou entre extremos, como consequência de fenômenos geológicos naturais. Porém, especialmente a partir do século XX, algumas atividades antrópicas estão alterando o clima, ocasionando oscilações de temperatura em toda a biosfera. Como resultado, uma série de alterações nos sistemas ecológicos vem sendo percebidos e registrados, colocando em risco a vida no planeta. Na expectativa de propor alternativas para resolver esse problema, foi criado o Painel Intergovernamental sobre Mudanças Climáticas (IPCC), um órgão internacional que publica relatórios de avaliação sobre a situação das mudanças climáticas. Atualmente está sendo elaborado o sexto relatório, com alguns resultados publicados nos anos de 2021 e 2022. O presente estudo teve como objetivo investigar a existência do aquecimento global e das suas consequências para a América Latina, a partir da análise dos relatórios do IPCC. Os resultados dos relatórios apontam a necessidade de mudança urgente na atual matriz energética baseada na queima de combustíveis fósseis, para a utilização de energias renováveis, com aumento de investimentos para adaptação e mitigação. Por fim, outros documentos elaborados pelo Programa das Nações Unidas para o Meio Ambiente (PNUMA) corroboram com os relatórios do IPCC, em especial a Agenda 2030 e os objetivos de desenvolvimento sustentável (ODS), com destaque para o objetivo 13 sobre mudanças climáticas. The influence of temperature on organisms is one of the essential aspects for the regulation and maintenance of life. Over geological time, the temperature on Earth has fluctuated between extremes, because of natural geological phenomena. However, especially since the 20th century, some anthropic activities are altering the climate, causing temperature fluctuations on the planet. As a result of these fluctuations, a series of changes in ecological systems have been perceived and recorded, putting life on the planet at risk. In the hope of proposing alternatives to solve this problem, the Intergovernmental Panel on Climate Change (IPCC) was created, an international body that publishes assessment reports about climate change. The sixth report is currently being prepared, with some results published in the years 2021 and 2022. The present work aimed to investigate the existence of global warming from the analysis of the IPCC reports, in addition to its consequences for Latin America. The results of the reports point to the need for an urgent change in the current energy matrix based on the burning of fossil fuels, for the use of renewable energies, with increased investments for adaptation and mitigation. In addition, documents prepared by the United Nations Environment Program (UNEP) corroborate the IPCC indications the 2030 Agenda with the goals of sustainable development (SDG). La influencia de la temperatura en los organismos es uno de los aspectos esenciales para la regulación y el mantenimiento de la vida en la Tierra. A lo largo del tiempo geológico, la temperatura en el planeta fluctuó entre extremos como consecuencia de fenómenos geológicos naturales. Sin embargo, especialmente a partir del siglo 20, algunas actividades antrópicas están alterando el clima, causando fluctuaciones de temperatura en el planeta. Como resultado de estas oscilaciones, se han percibido y registrado una serie de cambios en los sistemas ecológicos, poniendo en peligro la vida en el planeta. Con la expectativa de proponer alternativas para resolver este problema, se creó el Grupo Intergubernamental de Expertos sobre el Cambio Climático (IPCC), un organismo internacional que publica informes de evaluación sobre la situación del cambio climático. Actualmente se está preparando el sexto informe, con algunos resultados publicados en 2021 y 2022. El presente trabajo tuvo como objetivo investigar la existencia del calentamiento global a partir del análisis de los informes del IPCC, además de sus consecuencias para América Latina. Los resultados de los informes apuntan a la necesidad de un cambio urgente en la matriz energética actual basada en la quema de combustibles fósiles, para el uso de energías renovables, con mayores inversiones para la adaptación y mitigación. Además, los documentos elaborados por el Programa de las Naciones Unidas para el Medio Ambiente (PNUMA) corroboran las nominaciones del IPCC y, en particular, la Agenda 2030 con los objetivos de desarrollo sostenible (ODS).

Swine production chain generates residues with potential application in environmental processes. This study aimed at the use of swine hair as a potential biofilter for hexavalent chromium (Cr(VI)) removal from wastewater of tannery industry. The hair was pretreated using H2O2 in alkaline medium, and statistical analysis was carried out to evaluate the hair degradation, as well the Cr(VI) removal by the potential pretreated biofilter. The results showed 99% of Cr(VI) removal in 105 min of treatment in large pH range (1–10). Treated and untreated effluents were submitted to cytotoxicity study using vegetable and animal cells, demonstrating a significant reduction on toxicity to both cells. Therefore, swine hair demonstrated to be a promising residue for heavy metal removal on the perspective of an environmentally friendly technique.

The intense urbanization and use of natural resources has been causing disturbances in the aquatic ecosystem, such as the disorderly and dense increase of macrophytes, such as Eichhornia crassipes, Pistia stratiotes and Salvinia herzogii. In this context, we aim to evaluate the biological control of these plants by the production of phytopathogenic fungi compounds isolated from the foliar lesions of the plants collected. The microorganisms were isolated and identified as Aspergillus flavus and Aspergillus miniscleroti. Afterwards, an experimental design was developed and the results showed that temperature and glucose concentration were determinant in biomass production, being the largest biomass obtained 26.12 g/L and 45.95 g/L for A. flavus and A. miniscleroti, respectively. The application of the compounds in the plants showed satisfactory results, presenting toxicity potential in macrophytes, with a maximum deterioration of 88–94% for macrophytes E. crassipes.

This study aims to evaluate the production of compounds (fungal extract) from Trichoderma koningiopsis with herbicidal activity, as well as to analyze the effects of its application and ac...

Corn stands out among the cultivars because of its high importance in food, animal feed and raw materials for energy production. The quantity and quality of the harvested grain can be reduced, mainly due to inadequate weed management. Nowadays, weed control is accomplished with the use of herbicides as pre‐emergence and postemergence, applied alone or in a tank mix. This study aimed to evaluate the efficiency of the control of weeds and phytotoxicity of the herbicides that were applied in tank mix or isolated in the corn hybrids, Formula TL® and SYN 7B28. Two experiments were conducted: in the 2012/2013 season (Formula TL®) and 2013/2014 season (SYN 7B28). There was a low initial phytotoxicity of all the tested herbicides in the initial evaluation; however, from 14 days after treatment, it was minimal. The weed control of Ipomoea indivisa, Urochloa plantaginea and Euphorbia heterophylla in both experiments was better, in general, when using the tank mixtures of atrazine + simazine + tembotrione and atrazine + simazine + mesotrione, respectively. The application of atrazine + simazine + tembotrione in the SYN 7B28 hybrids provided, with the exception of the thousand‐grain weight, the best expression of grain yield components, combining a low phytotoxicity and best control of the weeds. The Formula TL® hybrid presented the highest mass of a thousand grains and yield with the application of nicosulfuron + tembotrione. The yield average difference of the herbicide treatments and the unweeded control showed an increase of 27.66 and 34.59% in the grain yield of the corn hybrids, Formula TL® and SYN 7B28, respectively.

The erva-mate (Ilex paraguariensis) represents an alternative crop for agricultural exploitation in South Brazilian farms with potential to export the harvested product. However, there is scarce information about the interference caused by weeds on this crop. The objective of this work was to evaluate the interference of weed species on the morphophysiological and nutritional characteristics of erva-mate. The experiment was installed in greenhouse at the Federal University of Fronteira Sul (UFFS), Campus Erechim/RS, Brazil, in randomized blocks design, arranged in a 4 × 6 factorial scheme, with four replications. In factor A, weed species (Urochloa plantaginea—Alexandergrass, Bidens pilosa—Hairy beggarticks, Ipomoea indivisa—Morning glory and Conyza bonariensis—Hairy fleabane) were allocated, and in B the populations of these species competing with the erva-mate (0, 1, 2, 3, 4 and 5 plants per pot) were considered. The variables evaluated in erva-mate were sub-stomatal CO2 concentration, photosynthetic rate, CO2 consumed, stomatal conductance, transpiration rate, water use efficiency, height, stem diameter, leaf area and shoot dry mass. Concentrations of nitrogen (N), phosphorus (P), calcium (Ca) and magnesium (Mg) were also evaluated. Overall, all weed species and densities among the tested ones harmed the development of erva-mate plants, which was considered as low competitive with weeds.

Wheat (Triticum aestivum) is one of the main cereals consumed in the world and is very important for food security. Harvest time and storage may influences physical and physiological quality, and also the fungal incidence in the grains. This work evaluated physical and physiological quality and fungal incidence in wheat grains of BRS Parrudo cultivar wheat at different harvest moisture contents and stored under hermetic and conventional conditions, PET bottles and kraft paper bags, respectively. Harvesting was done when wheat reached moisture contents (MCs) of 28.6, 18.5 and 12.9%, followed by drying at 38°C in a forced air circulation oven until MC was 13%. The wheat was then stored for 240 days. Quality evaluations were done after drying and every 60 days during the storage period. The quality of the wheat declined throughout the storage period, regardless of the MC, and harvest delay negatively affected quality. Fusarium spp. and other fungi declined while Aspergillus spp. and Penicillium spp. increased regardless of harvest MC or storage.

The work aimed to produce and characterize a biocompound based on Trichoderma koningiopsis; to evaluate the phytotoxic and morphological effects on cucumber plants (Cucumis sativus) model, and to study the ecotoxicity of the bioproduct in earthworms. The biocompound was produced by submerged fermentation to obtain the crude extract (ECd), filtered solution with filter paper (FilP), and gauze (FilG). From the ECd, the activity of the enzyme's amylases, cellulases, lipases, and total peroxidases was determined, with three replicates. Among the evaluated enzymes, a high concentration of total peroxidases (44 U mL−1) was observed. The ECd, FilP, and FilG biocompound preparations were applied to cucumber plants, isolated, and combined with the commercial herbicide based on potassium glyphosate. The FilG treatment caused the control of up to 80% of the cucumber plants 15 days after application. However, when FilG was combined with the herbicide glyphosate potassium, there was total depigmentation of 95% of the leaves and mortality of more than 90% of the cucumber plants. In evaluating ecotoxicity with earthworms (Eisenia andrei), there was no mortality when the organisms were exposed to the biocompound preparations; however, 68% rejected the biocompound associated with commercial herbicide was observed. In this way, T. koningiopsis biocompound demonstrated the potential action as a bioherbicide, with relevant data for the agricultural sector, to search for alternative methods to reduce costs and promote food and environmental security.

This study aims to evaluate the activity of the cellulase enzyme forward the use of ultrasound technology in different conditions of temperature, pH and exposure time, as well, to match the steps o...

Alternative sources for weed control are necessary to reduce the use of synthetic herbicides. Bioherbicides obtained from agro-industrial waste have the potential to integrate sustainable management of existing agricultural systems. Because of the need for new compounds with potential herbicide, this study's objective was to evaluate the bioherbicidal effect and the enzymatic activity of the extracts produced using agro-industrial waste as a substrate. A submerged fermentation was carried out with orange peel and shrimp shell; Trichoderma koningiopsis and Rhizopus stolonifer were used separately to produce enzymatic extracts. Through submerged fermentation with these agro-industrial residues, extracts were obtained, which were characterized concerning the activities of pectinase, cellulase, amylase, laccase, and peroxidase. The extracts were also evaluated for their bioherbicidal potential for weed control, and this is the first study conducted with these residues for this purpose. No significant difference was observed in the enzymatic activities of the extracts produced by the different microorganisms used. Accentuated leaf damage was observed in C. sativus seven days after applying both extracts, ranging from 66.67 to 77.08% for extracts of T. koningiopsis and R. stolonifer, respectively. Therefore, the extracts appear to be promising alternatives in weed control just seven days after application, demonstrating a rapid effect with low environmental risk.

Inulinase from Aspergillus niger was immobilized in polyurethane foam (PU). Immobilized catalyst was treated in pressurized liquefied petroleum gas (LPG) system. This biocatalyst was used in the fructooligosaccharide production using sucrose as substrate in aqueous system. The main objective of this study was to evaluate the reaction yield and productivity by using polyurethane foam as a low-cost support for enzyme immobilization in an alternative processes for fructooligosaccharide production in pressurized LPG system with potential for industrial application. The total FOS concentration obtained were 31% as a result of sucrose concentration reduction, and formation of FOS long chain (GF3 and GF4) from kestose (GF2). FOS concentrations of 5%, 22%, and 3% were obtained for GF2, GF3, and GF4, respectively. The methodology suggested in this research work, enzyme immobilization in a low-cost support, and treatment in LPG, showed potential technology for fructooligosaccharide synthesis.

In this study the interference of potassium phosphate, sodium citrate, sodium chloride and sodium nitrate salts on protein quantification by Bradford's method was assessed. Potassium phosphate and sodium citrate salts are commonly used in aqueous two-phase systems for enzyme purification. Results showed that the presence of potassium phosphate and sodium citrate salts increase the absorbance of the samples, when compared with the samples without any salt. The increase in absorptivity of the solution induces errors on protein quantification, which are propagated to the calculations of specific enzyme activity and consequently on purification factor. The presence of sodium chloride and sodium nitrate practically did not affect the absorbance of inulinase, probably the metals present in the enzyme extract did not interact with the added salts.

Meliponinae eusocial bees are among the most important pollinators in the Neotropics and their beekeeping has been growing as both recreational and economic activity. Information on the pollen preferences and niche overlap among species coexisting in the same location is still scarce. This study focused on the use of pollen resources by three native species of Meliponinae in the Atlantic Forest, Melipona quadrifasciata quadrifasciata (Lepeletier 1836), Scaptotrigona depilis (Moure 1942), and Tetragonisca angustula (Latreille 1811), at two different sites. The use of pollen resources was evaluated from reserves inside hives collected monthly between February 2015 and January 2016. It was also estimated the Mean Minimal Distance (Dm) traveled by the bees to obtain pollen. The bees differed regarding the diversity of pollen types, Dm, and proportion of pollen from different plant life-form. Local factor promoted differences only for Dm. M. q. quadrifasciata foraged a low diversity of pollen species and traveled greater distances with a higher proportion of trees plus palm species. Tetragonisca angustula foraged a higher diversity of pollen and flew shorter distances with a lower proportion of trees and palms. The species factor predominates over the local factor in the clustering pattern, based on pollen profile similarity. Meliponinae eusocial bees are among the most important pollinators in the Neotropics and their beekeeping has been growing as both recreational and economic activity. Information on the pollen preferences and niche overlap among species coexisting in the same location is still scarce. This study focused on the use of pollen resources by three native species of Meliponinae in the Atlantic Forest, Melipona quadrifasciata quadrifasciata (Lepeletier 1836), Scaptotrigona depilis (Moure 1942), and Tetragonisca angustula (Latreille 1811), at two different sites. The use of pollen resources was evaluated from reserves inside hives collected monthly between February 2015 and January 2016. It was also estimated the Mean Minimal Distance (Dm) traveled by the bees to obtain pollen. The bees differed regarding the diversity of pollen types, Dm, and proportion of pollen from different plant life-form. Local factor promoted differences only for Dm. M. q. quadrifasciata foraged a low diversity of pollen species and traveled greater distances with a higher proportion of trees plus palm species. Tetragonisca angustula foraged a higher diversity of pollen and flew shorter distances with a lower proportion of trees and palms. The species factor predominates over the local factor in the clustering pattern, based on pollen profile similarity.

The prospection of bioherbicides has been an alternative to weed control, aiming at mitigating chemical risks to human, animal and environmental health due to extreme use of synthetic herbicides. In the present study, various fungi were isolated from plants with symptoms of fungal diseases for bioherbicide purposes against weeds (Urochloa plantaginea, Euphorbia heterophylla and Bidens pilosa). Fungi isolated were identified by molecular methods and enzymatic products obtained by fungi fermentation (cellulase, lipase, peroxidase, and amylase) were quantified. Bioherbicide selectivity study was performed on crops (soybean and corn), as well as on resistant weeds. Among the isolated fungi, Fusarium oxysporum, Fusarium ploriferatum, and Trichoderma koningiopsis presented bioherbicide potential. T. koningiopsis, in particular, presented the highest effect on Euphorbia heterophylla (popular name - Mexican fire plant), causing up to 60% of foliar damage, without presenting phytotoxicity against corn crop. New perspectives for weeds control and their use in corn crops were prospected, considering the bioherbicide selectivity described in this study.

When plants are subjected to competition, their physiological behavior changes. To understand the developmental physiology of weeds will subsidize the development of cropping systems which favor the crops plants in detriment of weeds. The objective of this work was to evaluate the physiological behavior of different weed species, growing under intraspecific competition. Greenhouse experiment was conducted in randomized complete block design arranged in factorial scheme 4 × 5 with four replications. Factor A was the weed species [Urochloa plantaginea (Alexandrergrass), Bidens pilosa (hairy beggarticks), Ipomoea indivisa (morningglory) and Conyza bonariensis (hairy fleabane)], and factor B was the plant density of these species (20, 40, 60, 80 or 100 plants m-2). The following variables were evaluated: sub-stomatal CO2 concentration, photosynthesis rate, consumed CO2, stomatal conductance, transpiration rate, water use efficiency, plant height, shoot diameter, leaf area, and shoot dry biomass. Alexandergrass relies on the superior control of stomatal opening and high water use efficiency. Hairy beggarticks efficiency in competition lies on its ability to remove water from soil to levels when the other surrounding plant species would undergo stress. Morning glory and hairy fleabane did not present detectable particular features in the study, and their importance as weeds is probably tied to other survival abilities but superior competition. In conclusion, the weed species studied present distinct competitive strategies.

In this study, we evaluated the concentration of lipases from Aspergillus niger using efficient and low-cost methods aiming at application in the treatment of waste cooking oils. The change in ionic strength of the medium by the addition of salt and precipitation with ethanol increased the specific activity from 2.90 to 28.50 U/mg, resulting in a purification factor of 9.82-fold. The use of acetone resulted in a specific activity of 33.63 U/mg, resulting in a purification factor of 11.60-fold. After that, the concentrated lipase was used in the hydrolysis of waste cooking oil and 753.07 and 421.60 µmol/mL of free fatty acids were obtained for the enzyme precipitated with ethanol and acetone, respectively. The hydrolysis of waste cooking oil catalyzed by homemade purified lipase in ultrasonic media can be considered a pretreatment of oil by converting a significant amount of triglycerides into free fatty acids.