Balancing of some endogenous phytohormone on growth and development of sacred lotus (Nelumbo nucifera) after spraying of GA₃ application

Sacred lotus is an important cut floricultural crop in Thailand, the crop enters dormancy in mild winter, which prevents its year-round production.
The poor growth in low temperature conditions resulted in too little supply of flowers on the market.
The experiment aimed to clarify some strategies for improving flower quantity and quality in sacred lotus off-season production.
The study of gibberellic acid (GA₃) application on the changes of some endogenous phytohormones such as trans-zeatin riboside (t-ZR), abscisic acid (ABA) and gibberellin-like substances (GLS), growth and plant development.
The experiment was conducted in completely randomized design with different concentrations of GA₃ solutions: 200 and 400 mg L^‑1 applied monthly for three consecutive months.
Control plants were not treated with GA₃. When the plant reaches 3 months (145 days after first treatment, DAT), it was found that increasing GA₃ concentration gave the greatest in total leaf number, leaf stalk length, and stolon length.
No effect of GA₃ application on flower quality (flower number and flower FW and DW) was observed.
Plants treated with 400 mg L^‑1 of GA₃ showed the highest t-ZR content in stolons and tended to reduce GLS in plant parts compared to control plants.
GA₃ application reduced ABA content in leaves, but not influenced t-ZR level in nodes.
This balancing of endogenous phytohormone findings might be beneficial for applying the PGRs to control flowering in further aspects.

XIV International Symposium on Flower Bulbs and Herbaceous Perennials

P. Hongpakdee, S. Suangto, C. Inkham, S. Ruamrungsri

gibberellin-like substances, ABA, t-ZR, flowering, off-season sacred lotus

https://doi.org/10.17660/ActaHortic.2025.1435.26