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, Z-isomer of the potassium salt of 2-amino-3-methoxycarbonylacrylic acid and 1-methyl-3-methylamino-maleimide) have been synthesized and their growth-regulating properties investigated. Laboratory testing and field experiments revealed new compounds are highly effective environmentally friendly plant growth regulators 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.