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Soybean represents a valuable source of food for humans and animals and the quality of the seeds has great importance for the establishment and high productivity of this crop. Soybean seeds require continuous improvement, which is dependent on a better understanding of the regulatory mechanisms that coordinate seed germination. To investigate whether the method of water absorption into soybean seeds could lead to abnormal seedlings, and if this could be associated with cytogenetical consequences, we premoistened the seeds of three cultivars; M 6410 IPRO, M6210 IPRO, and BMX Potência RR by direct immersion (fast method), use of a wet substrate (intermediate method), and by moist atmosphere (slow method) with distilled water at 25ºC for 24 hours. We investigated the normal and abnormal seedlings, electrical conductivity, mitosis, cell death, and the chromosomal abnormalities index. The comet assay was applied to investigate DNA fragmentation. Direct immersion in water induced seedling growth inhibition and caused cytological alterations associated with genotoxicity effects in the studied soybean genotypes. Slow premoistening of the seeds increased seedling performance as a result of higher final germination percentage (above 85%), reduced abnormal seedlings (below 5%, on average), and reduced the electrical conductivity of seeds. All three genotypes of soybean seeds lost their ability to withstand the imbibitional damage induced by direct immersion as abnormal seedlings increased. We concluded that the fast water absorption by seeds poses a threat to genomic integrity owing to its potential for genotoxicity to DNA, manifesting as breaks or loss of whole chromosomes. Slow premoistening of the seeds resulted in a longer time period to deal with damage. Stabilized seedling growth was provided by altering cytogenetic responses during uptake of water by soybean seeds through the maintenance of cell viability. Soybean represents a valuable source of food for humans and animals and the quality of the seeds has great importance for the establishment and high productivity of this crop. Soybean seeds require continuous improvement, which is dependent on a better understanding of the regulatory mechanisms that coordinate seed germination. To investigate whether the method of water absorption into soybean seeds could lead to abnormal seedlings, and if this could be associated with cytogenetical consequences, we premoistened the seeds of three cultivars; M 6410 IPRO, M6210 IPRO, and BMX Potência RR by direct immersion (fast method), use of a wet substrate (intermediate method), and by moist atmosphere (slow method) with distilled water at 25ºC for 24 hours. We investigated the normal and abnormal seedlings, electrical conductivity, mitosis, cell death, and the chromosomal abnormalities index. The comet assay was applied to investigate DNA fragmentation. Direct immersion in water induced seedling growth inhibition and caused cytological alterations associated with genotoxicity effects in the studied soybean genotypes. Slow premoistening of the seeds increased seedling performance as a result of higher final germination percentage (above 85%), reduced abnormal seedlings (below 5%, on average), and reduced the electrical conductivity of seeds. All three genotypes of soybean seeds lost their ability to withstand the imbibitional damage induced by direct immersion as abnormal seedlings increased. We concluded that the fast water absorption by seeds poses a threat to genomic integrity owing to its potential for genotoxicity to DNA, manifesting as breaks or loss of whole chromosomes. Slow premoistening of the seeds resulted in a longer time period to deal with damage. Stabilized seedling growth was provided by altering cytogenetic responses during uptake of water by soybean seeds through the maintenance of cell viability.

The conversion of riparian forests into agricultural land results in the loss of water quality and aquatic biota health. The objectives of this study were therefore to determine the proportion of land use with emphasis on the type of vegetation cover; evaluate the limnological parameters and concentration of inorganic elements in the water of the São José stream in the Dourados River Basin, Mato Grosso do Sul, Brazil; correlate land use with the concentrations of inorganic elements in water; and evaluate the risk to preservation aquatic biota and in situ toxic effect on Astyanax lacustris. We collected samples from the São José Stream in 2020 and evaluated land use with high resolution aerial images. The inorganic elements in water samples were quantified using inductively coupled plasma optical emission spectrometry. In the surroundings of the São José stream, a reduction in riparian forest was observed with a proportion of only 16.32% of the area and the predominance of agricultural areas with 75.06%. The concentrations of dissolved oxygen (1.510 mg L-1) and P (> 0.235 mg L-1) in the water did not comply with the national legislation. In addition, Al and P indicated risks regarding the conservation of aquatic biota (risk quotient >1). The in situ evaluation of A. lacustris also revealed toxicity in the water. The results indicate environmental imbalance in the São José stream, requiring mitigation measures for its restoration and the sustainable use of its resources. Resumo A conversão de floresta ripária em áreas agrícolas resulta na perda da qualidade da água e da saúde da biota aquática. Assim, os objetivos deste estudo foram determinar a proporção de uso do solo com ênfase no tipo de cobertura vegetal; avaliar os parâmetros limnológicos e a concentração de elementos inorgânicos na água do córrego São José na Bacia do Rio Dourados, Mato Grosso do Sul, Brasil; correlacionar o uso do solo com as concentrações de elementos inorgânicos na água; e avaliar o risco para preservação da biota aquática e efeito tóxico in situ em Astyanax lacustris. Amostras de água do córrego São José foram coletadas em 2020 e avaliado o uso do solo com imagens aéreas de alta resolução. Os elementos inorgânicos nas amostras de água foram quantificados por espectrofotometria de emissão óptica de plasma indutivamente acoplado. No entorno do córrego São José, observou-se a redução da floresta ripária com proporção de 16,32% da área e a predominância de áreas agrícolas com 75,06%. As concentrações de oxigênio dissolvido (1,500 mg L-1) e P (> 0,235 mg L-1) apresentaram valores em desacordo com a legislação nacional. Além disso, Al e P indicaram riscos quanto à conservação da biota aquática (quociente de risco >1). A avaliação in situ de A. lacustris também revelou toxicidade na água. Os resultados indicaram desequilíbrio ambiental no córrego São José e, portanto, requerem medidas mitigadoras para sua recuperação e o uso sustentável de seus recursos.