title: Poly(3-hydroxybutyrate)/metribuzin formulations: characterization, controlled release properties, herbicidal activity, and effect on soil microorganisms.
abstract: Slow-release formulations of the herbicide metribuzin (MET) embedded in the polymer matrix of degradable poly-3-hydroxybutyrate [P(3HB)] in the form of microparticles, films, microgranules, and pellets were developed and tested. The kinetics of polymer degradation, MET release, and accumulation in soil were studied in laboratory soil microecosystems with higher plants. The study shows that MET release can be controlled by using different techniques of constructing formulations and by varying MET loading. MET accumulation in soil occurs gradually, as the polymer is degraded. The average P(3HB) degradation rates were determined by the geometry of the formulation, reaching 0.17, 0.12, 0.04, and 0.05 mg/day after 60 days for microparticles, films, microgranules, and pellets, respectively. The herbicidal activities of P(3HB)/MET formulations and commercial formulation Sencor Ultra were tested on the Agrostis stolonifera and Setaria macrocheata plants. The parameters used to evaluate the herbicidal activity were plant density and the weight of fresh green biomass measured at days 10, 20, and 30 after sowing. All P(3HB)/MET formulations had pronounced herbicidal activity, which varied depending on MET loading and the stage of the experiment. In the early phases of the experiment, the herbicidal effect of P(3HB)/MET formulations with the lowest MET loading (10 %) was comparable with that of the commercial formulation. The herbicidal effect of P(3HB)/MET formulations with higher MET loadings (25 and 50 %) at later stages of the experiment were stronger than the effect of Sencor Ultra.
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036. volova45@mail.ru.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Volova
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036.
authors.forename: Natalia
authors.initials: N
authors.lastname: Zhila
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036.
authors.forename: Evgeniy
authors.initials: E
authors.lastname: Kiselev
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036.|Siberian Federal University, 79 Svobodny Ave., Krasnoyarsk, Russian Federation, 660041.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Prudnikova
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036.
authors.forename: Olga
authors.initials: O
authors.lastname: Vinogradova
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036.
authors.forename: Elena
authors.initials: E
authors.lastname: Nikolaeva
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036.
authors.forename: Anna
authors.initials: A
authors.lastname: Shumilova
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036.
authors.forename: Anna
authors.initials: A
authors.lastname: Shershneva
authors.affiliation: Institute of Biopshysics of Siberian Branch of Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, Russian Federation, 660036.
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Shishatskaya
mesh_terms: D031703:Agrostis / Q000187:drug effects; D003692:Delayed-Action Preparations; D006540:Herbicides / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D006885:Hydroxybutyrates / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D007700:Kinetics; D011091:Polyesters / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D032983:Setaria Plant / Q000187:drug effects; D012987:Soil; D012988:Soil Microbiology; D014227:Triazines / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D000094122:Polyhydroxybutyrates
chemical_list: D003692:Delayed-Action Preparations; D006540:Herbicides; D006885:Hydroxybutyrates; D011091:Polyesters; D012987:Soil; D014227:Triazines; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates; C009235:metribuzin
keywords: Agrostis stolonifera; Degradable poly-3-hydroxybutyrate; Metribuzin; Release kinetics; Setaria macrocheata; Slow-release P(3HB)/MET formulations