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Plant regulators are studied because they can alter commercially significant aspects of plant growth. Gibberellic acid (GA3) exemplifies this, as it plays a crucial role in the growth and flowering processes of various vegetables. Thus, the present study sought to verify the effects caused by the exogenous application of different doses of the plant regulator GA3 on the floral, vegetative, and physiological patterns of the orchid Oncidium baueri. The sprayed doses were: 0, 50, 100, 200, and 400 mg L-1 of GA3. The parameters measured were: pseudobulb length (PL) and width (PW), leaf length (LL), leaf width (LW), number of leaves per plant (NL); time for flower spike to sprout (TFSS), time for flowers to open fully (TFOF), and time for flowers to fall (TFF), these measured in days; flower stem size (FSS), number of flowers per stem (NFS), chlorophyll a fluorescence (fv/fm), and stomatal conductance (Gs). The concentration of 200 mg L-1 of GA3 increased CP and CF by 3 cm, and NL also increased compared with the other concentrations. Regarding floral aspects, this same dose showed the lowest TFSS, distinguishing itself from the other treatments. For physiological parameters, this dose also resulted in higher fv/fm (0.826) and Gs (65.340 mmol m-2 s-1). Therefore, the use of 200 mg L-1 of GA3 is recommended for O. baueri plants to optimize vegetative and floral promotion.

Sericulture is the cultivation of silkworms to produce silk using white mulberry leaves (Morus alba L.); thus, the sector's quality production of mulberry seedlings on a large scale is economically important. The production of seedlings through cuttings is the most effective and fastest reproduction method. Still, it can also be enhanced using synthetic rooting agents, increasing the productive potential of white mulberry crops. The current work aims to evaluate the response of cuttings taken from different parts of the branch of M. alba var. Miura (Apical 1, Apical 2, Medial, Basal 1, and Basal 2) and treated with indolebutyric acid (IBA; 500, 1,000, and 1,500 mg L-1) and commercial rooting agent Forth® (10 % v/v), in addition to a control treatment. After treating the branches, they were placed in polyethylene containers filled with substrate and kept in a greenhouse for 70 days. The application of hormones on cuttings of M. alba favored several morpho-agronomic parameters evaluated for the propagules obtained from different positions on the branch. In conclusion, applying 500 or 1,000 mg L-1 of IBA is recommended for the various positions, with Basal 1 and Basal 2 showing higher values ​​in the evaluated parameters than the other positions. The results can help silk breeders optimize white mulberry crop production.