Slow-Release Nitrogen Fertilizers with Biodegradable Poly(3-hydroxybutyrate) Coating: Their Effect on the Growth of Maize and the Dynamics of N Release in Soil

Abstract

Fertilizers play an essential role in agriculture due to the rising food demand. However, high input fertilizer concentration and the non-controlled leaching of nutrients cause an unwanted increase in reactive, unassimilated nitrogen and induce environmental pollution. This paper investigates the preparation and properties of slow-release fertilizer with fully biodegradable poly(3-hydroxybutyrate) coating that releases nitrogen gradually and is not a pollutant for soil. Nitrogen fertilizer (calcium ammonium nitrate) was pelletized with selected filler materials (poly(3-hydroxybutyrate), struvite, dried biomass). Pellets were coated with a solution of poly(3-hydroxybutyrate) in dioxolane that formed a high-quality and thin polymer coating. Coated pellets were tested in aqueous and soil environments. Some coated pellets showed excellent resistance even after 76 days in water, where only 20% of the ammonium nitrate was released. Pot experiments in Mitscherlich vegetation vessels monitored the effect of the application of coated fertilizers on the development and growth of maize and the dynamics of N release in the soil. We found that the use of our coated fertilizers in maize nutrition is a suitable way to supply nutrients to plants concerning their needs and that the poly(3-hydroxybutyrate) that was used for the coating does not adversely affect the growth of maize plants.

Live soil ameliorated the negative effects of biodegradable but not non-biodegradable microplastics on the growth of plant communities

“…2019). However, in agreement with the present finding where the biodegradable microplastic PHB did not significantly influence total shoot biomass of plant communities ( Figure 2d ), a previous study did not find significant adverse effect of PHB on growth of Zea mays (maize) (Kontárová et al . 2022).…”

“…The present finding that PBS significantly suppressed plant community productivity (Figure 2a) contrasts with that of another study that found that PBS did not have adverse effects on the growth of Brassica rapa (Chinese cabbage) (Wang et al 2019). However, in agreement with the present finding where the biodegradable microplastic PHB did not significantly influence total shoot biomass of plant communities (Figure 2d), a previous study did not find significant adverse effect of PHB on growth of Zea mays (maize) (Kontárová et al 2022). In contrast to the present findings of non-significant effects of non-biodegradable microplastics PET and PVC on the plant communities (Figure 2h & i), other studies found inhibitory effects of PET on Lepidium sativum (garden cress) (Pignattelli et al 2021) and PVC on Triticum aestivum (wheat) (Xinyue et al 2021).…”

Biodegradable Dextrin-Based Microgels for Slow Release of Dual Fertilizers for Sustainable Agriculture

“…The abundance of chlorophyll is directly impacted by the amount of nitrogen present in plant tissues . The slow release of urea from the developed PDXE MGs, and the direct use of pure urea were compared to explain the impact of N on chlorophyll content . To investigate the effect of developed formulation, we measured the proportion of chlorophyll in maize leaves grown in the soil treated with bare urea, Urea@PDXE MGs, and pure water as a control.…”

“…58 The slow release of urea from the developed PDXE MGs, and the direct use of pure urea were compared to explain the impact of N on chlorophyll content. 59 To investigate the effect of developed formulation, we measured the proportion of chlorophyll in maize leaves grown in the soil treated with bare urea, Urea@PDXE MGs, and pure water as a control. Our results suggested that the application of Urea@PDXE MGs (90 ± 0.7 mg/g) improved the amount of chlorophyll in maize leaves (Table 4, Figure S7), which can be ascribed to the correlation between chlorophyll synthesis and the amount of nitrogen in the leaves.…”