“…The in vitro germination of some species, such as Maclura tinctoria, Cocos nucifera, and Syagrus coronata, has been increased by supplying the medium with GA 3 (Gomes et al, 2010;Medeiros et al, 2015;Montero-Cortés et al, 2011). This growth regulator could be important for cell growth and elongation, leaf expansion and photosynthetic processes, as well as for the activity of important metabolic enzymes, such as nitrate reductase (Gupta;Chakrabarty, 2013, Bezerra et al, 2019. Enhancement of nitrate reductase activity may be beneficial, since this enzyme is responsible for the assimilation of nitrogen, an essential element found in many macromolecules and components of secondary metabolism, including proteins, nucleic acids, cell wall components, hormones, and vitamins (Krapp, 2015).…”