Uso de corantes alternativos em lâminas histológicas vegetais

Abstract

To better understand botany, the study of plant tissues, observed microscopically, has emerged. However, to better analyze these tissues, the use of dyes is necessary to allow better visualization of the cells. Nonetheless, the dyes typically used can be difficult to access due to their high financial cost. Thus, this work aims to use low-cost textile dyes to replace synthetiones, resulting in the creation of a plant histological slide set, minimizing costs and making the technique accessible to all. One species of garden plant was selected and collected, and freehand cross-sections were performed according to methodologies applied in plant histology. For staining, textile dyes from brands labeled “A” and “B” were used. These were diluted in a 50% hydroalcoholic solution at a ratio of 1g of dye to 20 ml of solution, filtered with paper to remove excess dye powder, and transferred to a sealed and properly labeled glass container stored at room temperature. The histological sections were immersed in the dye inside a closed Petri dish for an average time of 40–60 minutes. Then, a wash with distilled water was performed to remove excess dye, and the samples were placed in a fixative, also manufactured by brand “B” for one minute. Finally, the slides were mounted with 50% glycerin for microscopic observation. It was found that the powdered dyes have an effective staining capacity for plant tissues, particularly highlighting lignified tissues and facilitating cell visualization. As a result, it was possible to create a histological slide set containing eight slides with cross-sections of monocotyledon stems, suitable for educational use in practical plant anatomy classes.