Synthesis, Characterization, and Encapsulation of Novel Plant Growth Regulators (PGRs) in Biopolymer Matrices

Abstract

Novel plant growth regulators (PGRs) based on the derivatives of dehydroamino acids 2,3-dehydroaspartic acid dimethyl ester (PGR1), Z-isomer of the potassium salt of 2-amino-3-methoxycarbonylacrylic acid (PGR2) and 1-methyl-3-methylamino-maleimide (PGR3) have been synthesized and their growth-regulating properties investigated. Laboratory testing revealed their plant growth-regulating activity. PGR1 showing the most stimulating activity on all laboratory tested cultures were used in field experiments. Results showed that PGR1 is a highly effective environmentally friendly plant growth regulator with effects on different crops. Biopolymeric microcapsule formulations (chitosan/alginate microcapsule loaded with PGR) suitable for application in agriculture were prepared and characterized. Physicochemical properties and release profiles of PGRs from microcapsule formulations depend on the molecular interactions between microcapsule constituents including mainly electrostatic interactions and hydrogen bonds. The differences in the microcapsule formulations structure did not affect the mechanism of PGRs release which was identified as diffusion through microcapsules. The obtained results opened a perspective for the future use of microcapsule formulations as new promising agroformulations with a sustained and target release for plant growth regulation.

The Impact of Chitosan and Tithonia Diversifolia Compost on the Growth and Yield of Peanut Plants (Arachis hypogaea L.)

“…Chitosan can stimulate the production of growth-regulating hormones in plants, such as auxin and gibberellins, which are involved in plant growth and development. Auxin promotes photosynthesis, while gibberellins contribute to flower and fruit formation, potentially affecting seed weight [34]. However, in this experiment, the application of chitosan alone was not sufficient to significantly increase the weight of peanut seeds.…”

Development and Characterization of a Novel Soil Amendment Based on Biomass Fly Ash Encapsulated in Calcium Alginate Microspheres

“…In vitro release studies of microspheres were carried out at room temperature in the system formed by putting 4 g of microspheres in 100 mL of distilled water, as previously described [ 45 ]. The concentrations of released K, Ca, and Mg were determined by atomic absorption spectrometry (ASS) (HRN ISO 11466:2004).…”

Carrier‐based delivery system of phytohormones in plants: stepping outside of the ordinary

“…Interestingly, polysaccharides/biopolymers can be utilized either independently or in combination with other polymers to create nanoparticles (Vinzant et al, 2023). These systems improve the stability and lengthen the duration of action of the active ingredients as Alginate/ chitosan (ALG/CS) and chitosan/tripolyphosphate (CS/TPP) nanoparticles are used in sustained release systems as medication and agrochemical carriers (Grillo et al, 2014;Silva et al, 2010).…”

“…In ionic gelation and polyelectrolyte complexation methods, microcapsules are synthesized by dissolving different phytohormones in sodium alginate under continuous stirring (Kudasova et al, 2021; Riseh et al, 2024). Then, drop by drop addition of the calcium chloride suspension initiates the bead formation (Vlahovicek‐Kahlina et al, 2021). Similarly, chitosan microspheres loaded with auxin were prepared by emulsion cross‐linking method in which chitosan, ethyl benzoate and IAA solution were mixed in the presence of 5% Span‐80 with continuous stirring at room temperature (Fan et al, 2012).…”