Effects of gibberellic acid concentration and fruit maturation stage on seed germination and vigor of pitahaya seedlings

Abstract

With increased interest in cultivation, the study of white-fleshed pitahaya (Selenicereus undatus (Haw.) D.R. Hunt, Cactaceae family) seedling production is of fundamental importance in the search for novel techniques to increase cultivation and guarantee homogeneous and productive orchards. The present study investigated the influence of various gibberellic acid (GA3) concentrations and fruit maturation stages on seed germination and vigor of white-fleshed pitahaya seedlings, considering the physiological quality of seedlings produced to support genetic breeding and conservation programs of the species. White-fleshed pitahaya seeds at two maturation stages (physiologically ripe and maintained at 10 °C in Biochemical Oxygen Demand incubators for three months) were treated with varying GA3 concentrations of 0, 50, 100, and 500 mg/L. We observed the influence of fruit storage on seedling germination, emergence, and growth as a function of GA3 concentration. According to the results, seeds extracted from ripe white-fleshed pitahaya fruits grown under the conditions tested here required GA3 application to increase seedling emergence and vigor, with optimal doses in the 150–300-mg/L range. In the case of pitahaya fruits intended for storage for future seed removal and maintained under the same sowing conditions, the application of higher doses of GA3 was necessary when compared to the previous condition, with a minimum dose of 500 mg/L GA3. The present study shows that the maturation stage of white-fleshed pitahaya fruits intended for seed removal influences the quality of seedlings; therefore, the use of seeds extracted from ripe pitahaya fruits without fermentation is more appropriate for the purpose.

In vitro germination of passion fruit seeds in the function of tegument removal and culture media

“…Removal of the aril, for example, by natural fermentation, chemical, and/ or mechanical techniques may stop dormancy and accelerate germination (Grzybowski et al, 2019). Gibberellic acid also accelerates seed dormancy, breaking and standardizing the germination process (Santos et al, 2022).…”

Phytohormones regulate asexualToxoplasma gondiireplication

“…Similarly, for cytokinins a dosage of 10 μM has been described (Andrabi et al 2018), which translates into 2.2 ng/μl for KIN, falling within our tested range of 1 to 50 ng KIN /μl. For GIBB, we did not find information about previous concentrations used in the apicomplexan model, however, we referred to concentrations typically used in plant experiments and designed a test concentration range of 2 to 250 ng GIBB /μl, which is in line with plant experimentation (Didi et al 2022, Santos et al 2022).…”