Abscisic acid (ABA) is an important plant hormone that regulates plant growth, signal transduction, and plant immune defense. Exogenous application of ABA has a variety of effects such as promoting the rooting and improving the drought resistance of crops, prolonging the flowering period, and increasing the fruit coloring rate. However, the half-life of ABA is only 24 min, and it is easy to isomerize and lose its biological activity under ultraviolet (UV) radiation, which increases the cost of field application of ABA. Under sunlight, nearly 50% of ABA can be converted to trans-ABA. Photodegradation products include 4-trans-3 methylene ABA and 4-cis-3-methylene. Potent and photostable ABA analogues were designed and synthesized. Further bioassays showed that under 150 mM salt stress, 10 nM a substituted benzoylaminocyclopropionic acid B2 could increase wheat biomass and salt resistance, and its mechanism of action was revealed at the biochemical and molecular level. In addition, the new plant growth regulator candidate showed improved photostability and showed better activity to inhibit wheat seed germination. To increase the photostability and biological activity of ABA, eco-friendly photoprotective agents were introduced for formulation preparation. Soluble 2-hydroxy-4-methoxybenzophenone-5-sodium sulfonate (BP-4) and lignosulfonates were found to be effective agents to maintain ABA activity under UV radiation. Approximately 26% and 52% ABA were kept when 280 mg/L ABA aqueous solution was irradiated by UV light for 2 h in the presence of 200 mg/L BP-4 and 2000 mg/L Ufoxane 3A, respectively. Recently, we encapsulated ABA into cetyltrimethylammonium bromide (CTAB) modified alkali lignin (AL) to induce the formation of self-assembly ABA@AL-CTAB nanoparticles. The controlled-release properties, anti-photolytic properties and thermal stability of ABA microcapsules have all proven to be excellent. In summary, it is very important to discover photostable ABA analogues and develop photoprotective ABA preparation. The latter is most likely to be used in agricultural production in the near future.

Discovery of photostable abscisic acid analogs and novel formulations

ACS Fall 2020 Virtual Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.