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Genetic diversity within a germplasm collection plays a vital role in the success of breeding programs. However, comprehending this diversity and identifying accessions with desirable traits pose significant challenges. This study utilized publicly available data to investigate SNP markers associated with protein and oil content in Brazilian soybeans. Through this research, twenty-two new QTLs (Quantitative Trait Loci) were identified, and we highlighted the substantial influence of Roanoke, Lee and Bragg ancestor on the genetic makeup of Brazilian soybean varieties. Our findings demonstrate that certain markers are being lost in modern cultivars, while others maintain or even increase their frequency. These observations indicate genomic regions that have undergone selection during soybean introduction in Brazil and could be valuable in breeding programs aimed at enhancing protein or oil content.

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MAIN CONCLUSION: Inbred line 11-133 of popcorn showed the lowest apoplast Al and total Al concentrations and Al-lumogallion complex, associated with a more efficient antioxidant system, mainly due to glutathione metabolism. Popcorn (Zea mays L. var. everta) is largely intended for human consumption. About 40% of the world's arable soils are acidic. In soils acidic, aluminum (Al) ionizes producing the trivalent cation, which is highly toxic to plants. Hence, this work aimed to: (1) evaluate the Al toxicity sites and its effect on the structure of the root tips, (2) quantify Al concentrations in the apoplast and symplast of the roots, and (3) to elucidate the modulation on the activity of antioxidant enzymes and metabolites of the ascorbate-glutathione cycle in two popcorn inbred lines (ILs) 11-133 and 11-60, classified as tolerant and sensitive to this metal, respectively. Aluminum toxicity did not affect the shoot growth; however, there was a yellowing of the oldest leaf blade only in 11-60. The better performance of 11-133 is related to lower apoplastic and total Al concentrations and Al accumulation in the root associated with a lower fluorescence of Al-lumogallion complex at the root tip, indicating the presence of mechanisms of chelation with this metal. Consequently, this IL showed less change in root morphoanatomy and lower reactive oxygen species and malondialdehyde content, which are associated with a more efficient enzymatic and non-enzymatic system, mainly due to the higher content of the glutathione metabolite and the higher activities of superoxide dismutase, monodehydroascorbate reductase, dehydroascorbate reductase, γ-glutamylcysteine synthetase, and glutathione peroxidase enzymes. Thus, these findings illustrated above indicate how internal mechanisms of detoxification respond to Al in popcorn, which can be used as tolerance biomarkers.

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Background: Soybean is the main oilseed crop grown in the world; however, drought stress affects its growth and physiology, reducing its yield. The objective of this study was to characterize the physiological, metabolic, and genetic aspects that determine differential resistance to water deficit in soybean genotypes. Methods: Three soybean genotypes were used in this study, two lineages (L11644 and L13241), and one cultivar (EMBRAPA 48-C48). Plants were grown in pots containing 8 kg of a mixture of soil and sand (2:1) in a greenhouse under sunlight. Soil moisture in the pots was maintained at field capacity until the plants reached the stage of development V4 (third fully expanded leaf). At this time, plants were subjected to three water treatments: Well-Watered (WW) (plants kept under daily irrigation); Water Deficit (WD) (withholding irrigation until plants reached the leaf water potential at predawn of -1.5 ± 0.2 MPa); Rewatered (RW) (plants rehydrated for three days after reached the water deficit). The WW and WD water treatments were evaluated on the eighth day for genotypes L11644 and C48, and on the tenth day for L13241, after interruption of irrigation. For the three genotypes, the treatment RW was evaluated after three days of resumption of irrigation. Physiological, metabolic and gene expression analyses were performed. Results: Water deficit inhibited growth and gas exchange in all genotypes. The accumulation of osmolytes and the concentrations of chlorophylls and abscisic acid (ABA) were higher in L13241 under stress. The metabolic adjustment of lineages in response to WD occurred in order to accumulate amino acids, carbohydrates, and polyamines in leaves. The expression of genes involved in drought resistance responses was more strongly induced in L13241. In general, rehydration provided recovery of plants to similar conditions of control treatment. Although the C48 and L11644 genotypes have shown some tolerance and resilience responses to severe water deficit, greater efficiency was observed in the L13241 genotype through adjustments in morphological, physiological, genetic and metabolic characteristics that are combined in the same plant. This study contributes to the advancement in the knowledge about the resistance to drought in cultivated plants and provides bases for the genetic improvement of the soybean culture.

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Soybean oil is the second most-produced vegetable oil worldwide. To enhance the nutritional quality and oxidative stability of soybean oil, many soybean breeding programs are trying to increase oleic acid content and reduce linoleic and linolenic acid contents. The fatty acid profile of soybean oil is controlled by many genes, including those which code for omega-3 and omega-6 desaturases. Mutations in GmFAD2-1 and GmFAD3 genes are widely studied and their combinations can produce soybean oil with high oleic and low linoleic and linolenic content. However, few studies evaluate the effect of these mutations on gene expression. Therefore, the present study sought to identify reference genes, evaluate the expression of GmFAD2-1 and GmFAD3 seed desaturase genes in thirteen wild-type and mutated soybean accessions, and associate the expression patterns with fatty acid composition and with the GmFAD2-1 and GmFAD3 genotypes. GmCONS7 and GmUKN2 were identified as the best reference genes for combined use to normalize data. The GmFAD2-1A mutation of PI603452 accession was associated with a decrease in gene expression of GmFAD2-1A; however, downregulation may not be due to the truncated enzyme structure alone. These results suggested that there are factors other than GmFAD2-1A and GmFAD2-1B that have a considerable effect on oleic content, at least in soybeans with mutations in these two genes.

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The herbicide glyphosate can cause severe ecotoxicological effects on non-target organisms. Eugenia uniflora L. (Myrtaceae) is very important for in situ environmental biomonitoring due to its wide distribution in the Atlantic Forest biome. Thus, this study aimed to evaluate the response of E. uniflora leaves to glyphosate. Eight-month-old plants were exposed to an aerial application of the herbicide at concentrations of 0, 144, 432, 864, and 1440 g a. e. ha-1 (grams of acid equivalent per hectare). Evaluations were performed on the 12th day after the glyphosate application (DAA). An accumulation of shikimic acid in the leaves of E. uniflora was observed. Glyphosate altered the photosynthetic parameters of the treated plants, with a drastic decrease in the photosynthetic rate, stomatal conductance, transpiration, and pigment content. There was an increase in Ci/Ca, lipid peroxidation, and electrolyte extravasation levels. Glyphosate also promoted ultrastructural, anatomical and visible damage to the E. uniflora leaves. Our findings indicate that glyphosate is phytotoxic to the native species E. uniflora at the tested doses. The presence of visible damage suggests that E. uniflora has remarkable potential as a bioindicator of glyphosate in the environment, making it a possible species for future biomonitoring projects.

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Glutathione is essential for plant tolerance to arsenic but few studies have focused on the coordination between the enzymes involved in its metabolism. We exposed Pistia stratiotes to four treatments (control, 5, 10 and 20 µM AsIII) for 24 h to evaluate the role of glutathione metabolism in arsenic response and determined the arsenic uptake, growth, membrane integrity, glutathione concentration and enzyme activities (γ-glutamyl-cysteine synthetase, glutathione reductase, glutathione peroxidase, and glutathione-S-transferase). Despite absorbing high concentrations of AsIII, plants maintained growth and cell membrane integrity when exposed to concentrations of up to 10 µM AsIII. The maintenance of these parameters involved glutathione concentration increase due to an increase in its biosynthetic pathway (higher γ-glutamyl-cysteine synthetase). In addition, an increase in the activity of glutathione reductase, glutathione peroxidase and glutathione-S-transferase also contributed to the conserve the cellular homeostasis. However, at the concentration of 20 µM AsIII, the high toxicity of AsIII affected glutathione concentration and glutathione metabolizing enzymes activities, which resulted in drastic decrease in growth and damage to cell membranes. These results showed that not only the glutathione concentration but also the coordination of the enzymes involved in the synthesis, oxidation and reduction pathways of glutathione is essential for AsIII tolerance.

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Por muito tempo, a exploração dos sistemas agrícolas em sua totalidade vem associado ao manejo inadequado dos agroecossistemas. Um dos problemas que afetam o processo de produção agrícola é a salinização do solo, pois elevados níveis de salinidade dificultam a absorção de água e nutrientes pelos vegetais convertendo-se em problemas de ordem nutricional, toxicológico, físico, químico, biológico e, em casos mais extremos, a salinidade do solo pode desencadear outro processo conhecido como desertificação, tornando o solo inapropriado para o cultivo. No ambiente protegido, o principal meio de adubação é a fertirrigação, cujas causas da salinidade são evidenciadas pelo uso excessivo de fertilizantes e pela má qualidade da água de irrigação que provém em sua maioria de poços com alto teor de cloreto de sódio (NaCl). Diferentemente do que ocorre em cultivos a campo, que há entrada de água, por meio da precipitação natural, a água que entra no ambiente protegido provém unicamente da irrigação, precipitação artificial, onde o método da irrigação localizada é utilizado pela maioria dos produtores. A salinização em ambiente protegido é independente das condições climáticas ou do tipo de solo empregado no cultivo, uma vez que ocorre um aumento da condutividade elétrica da solução do solo aliada a altas doses de adubos que proporcionam o acúmulo de sais na superfície. O presente trabalho teve como objetivo abordar por meio de uma revisão de literatura, os principais fatores que promovem o processo de salinização do solo em ambiente protegido.(AU)

For a long time, the exploration of agricultural systems in their entirety comes associated with the inadequate management of agroecosystems. One of the problems that affect the process of agricultural production is the soil salinization, because high levels of salinity hinder the water and nutrients absorption by vegetables, becoming nutritional, toxicological, physical, chemical, biological problems and in more extreme cases, soil salinity can trigger another process known as desertification, making the soil unsuitable for cultivation. In the protected environment the main means of fertilization is the fertigation, whose salinity causes are evidenced by the excessive use of fertilizers and by the poor quality of irrigation water that comes mostly from wells with high sodium chloride (NaCl) content. Contrary to what happens in field crops, where there is input of water through natural precipitation, water entering the protected environment comes solely from irrigation, artificial precipitation, where the irrigation method is located and used by most producers. The salinization in protected environment is independent of the climatic conditions or the type of soil used in the cultivation, once there is an increase in the electrical conductivity of the soil solution with high doses of fertilizers that provide the accumulation of salts on the surface. The present study had as objective to approach through a literature review, the main factors that promote the process of soil salinization in a protected environment.(AU)

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O substrato é um dos fatores de maior importância na produção de mudas de espécies frutíferas, pois garantem as melhores condições de crescimento e estabilidade das mudas no campo. Com isso, objetivou-se avaliar a produção de mudas de maracujazeiro amarelo (Passiflora edulis) com diferentes fontes e proporções de matéria orgânica. O delineamento experimental foi em blocos casualizados, em esquema fatorial 3x4, com 4 repetições, sendo três fontes de matéria orgânica (solo + areia (testemunha); solo + areia + esterco bovino; solo + areia + esterco de galinha e solo + areia + húmus) e quatro proporções (1:1:0, 1:1:1, 1:1:2, 1:1:3), com 10 mudas por tratamento. Foram realizadas avaliações diárias para determinar o índice de velocidade de emergência e a porcentagem de emergência, e aos 60 dias após a semeadura foram avaliados: altura de planta, número de folhas, comprimento radicular, relação H/D, diâmetro do caule, massa fresca e seca das folhas, caule, raiz e total. Com isso, o substrato orgânico contendo húmus e o esterco bovino foram os que propiciaram as melhores condições para produção de mudas de maracujazeiro amarelona proporção 1:1:1 e 1:1:2, respectivamente.(AU)

The substrate is one of the most important factors in the production of seedlings of fruit species, since they guarantee the best conditions of growth and stability of the seedlings in the field. The aim of this study was to evaluate the production of yellow passion fruit seedlings (Passiflora edulis) with different sources and proportions of organic matter. The experimental design was in randomized blocks, in a 3x4 factorial scheme, with 4 replicates, being three sources of organic matter (soil + sand (control), soil + sand + bovine manure, soil + sand + chicken manure and soil + sand + humus) and four ratios (1:1:0, 1:1:1, 1:1:2, 1:1:3), with 10 seedlings per treatment. Daily evaluations were performed to determine the rate of emergence and percentage of germination, and at 60 days after sowing, plant height, leaf number, root length, H/D ratio, stem diameter, fresh mass and dry leaves, stem, root and total. Thus, the organic substrate containing humus and bovine manure provided the best conditions for the production of yellow passion fruit seedlings in a ratio of 1:1:1 to 1:1:2, respectively.(AU)

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O substrato é um dos fatores de maior importância na produção de mudas de espécies frutíferas, pois garantem as melhores condições de crescimento e estabilidade das mudas no campo. Com isso, objetivou-se avaliar a produção de mudas de maracujazeiro amarelo (Passiflora edulis) com diferentes fontes e proporções de matéria orgânica. O delineamento experimental foi em blocos casualizados, em esquema fatorial 3x4, com 4 repetições, sendo três fontes de matéria orgânica (solo + areia (testemunha); solo + areia + esterco bovino; solo + areia + esterco de galinha e solo + areia + húmus) e quatro proporções (1:1:0, 1:1:1, 1:1:2, 1:1:3), com 10 mudas por tratamento. Foram realizadas avaliações diárias para determinar o índice de velocidade de emergência e a porcentagem de emergência, e aos 60 dias após a semeadura foram avaliados: altura de planta, número de folhas, comprimento radicular, relação H/D, diâmetro do caule, massa fresca e seca das folhas, caule, raiz e total. Com isso, o substrato orgânico contendo húmus e o esterco bovino foram os que propiciaram as melhores condições para produção de mudas de maracujazeiro amarelona proporção 1:1:1 e 1:1:2, respectivamente.

The substrate is one of the most important factors in the production of seedlings of fruit species, since they guarantee the best conditions of growth and stability of the seedlings in the field. The aim of this study was to evaluate the production of yellow passion fruit seedlings (Passiflora edulis) with different sources and proportions of organic matter. The experimental design was in randomized blocks, in a 3x4 factorial scheme, with 4 replicates, being three sources of organic matter (soil + sand (control), soil + sand + bovine manure, soil + sand + chicken manure and soil + sand + humus) and four ratios (1:1:0, 1:1:1, 1:1:2, 1:1:3), with 10 seedlings per treatment. Daily evaluations were performed to determine the rate of emergence and percentage of germination, and at 60 days after sowing, plant height, leaf number, root length, H/D ratio, stem diameter, fresh mass and dry leaves, stem, root and total. Thus, the organic substrate containing humus and bovine manure provided the best conditions for the production of yellow passion fruit seedlings in a ratio of 1:1:1 to 1:1:2, respectively.

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Purpose: Biofilm growth exerts a negative impact on industry and health, necessitating the development of strategies to control. The objective of this work was study the lytic activity of the phage isolated from the sewage network in the formation and degradation of Escherichia coli biofilms. Methods: E. coli cultures were incubated in 96-well polystyrene microplates under controlled conditions to evaluate the biofilm formation. The E. coli cultures and established biofilms were treated with the suspensions of the vB_EcoM-UFV017 (EcoM017) bacteriophage obtained from sewage for 24 hours. The E. coli bacterial density was measured using absorbance at 600 nm and the biofilms were measured by crystal violet staining. Polystyrene coupons were used as support for Scanning Electron Microscopy and Confocal Microscopy to evaluate biofilm formation. Results: The E. coli strains formed biofilms in polystyrene microplates after 48 hours' incubation. The highest EcoM017 phage titer, in the prevention and degradation experiments, reduced the bacterial growth and the quantity of biofilm formed by E. coli in 90.0% and 87.5%, respectively. The minimum dose capable of reducing the biofilms of this bacterium was 101 PFU/mL after 24 hours. The preformed E. coli biofilm mass was reduced 79% post exposure to the phage in the degradation assay. Microscopic analysis confirmed the results obtained in the plates assays. Conclusion: The EcoM017 phage prevented biofilm formation and degraded the E. coli-established ones. The EcoM017 phage isolated from sewage can reduce bacterial attachment and lyse the E. coli associated biofilm cells, offering biotechnological potential applicability for this phage.