The synergistic effect between heavy metals and microplastics can affect soil properties as well as plant performance and yield. The objective of this study was to evaluate the combined effect of microplastics and cadmium on a soil–plant system. Specifically, we proposed to explore changes in soil microbiological activity, the growth and yield parameters of strawberry plants, and to evaluate the accumulation of these pollutants in the soil and root system. Plants were planted in clay pots under greenhouse conditions. The experiment was set up as a completely randomized design, with four treatments (Control; MPs; Cd; and Cd + MPs) and five replicates. The results showed that MPs and/or Cd affected plant growth, plant biomass, the number of fruits, root characteristics, dehydrogenase activity, acid phosphatase, and microbial biomass, and increased the accumulation of Cd in the roots and soil. The increased bioavailability of Cd, due to the presence of microplastics, could explain the observed negative effects on soil properties and the performance of strawberry plants.

This work deals with optimising the cell survival of rhizobacteria encapsulated in alginate beads filled with starch. Immobilisation of rhizobacteria was done by dripping alginate-starch solution mixed with rhizobacteria into a calcium solution. Beads were analysed based on matrix formulation, bacteria growth phase, osmoprotectants and nature of calcium solution. Maximum cell recovery was obtained on Raoultella terrigena grown in medium supplemented with trehalose and calcium gluconate as gelling agent. Furthermore, dried beads containing Azospirillum brasilense presented 76% of viable cells after one year of storage. The survival of rhizobacteria during the bioencapsulation process can be improved by incorporating starch on beads composition, varying the growth phase of cells and using trehalose in growth culture medium. This work provides a selection of appropriate methods to improve the surviving rate of encapsulated cells during their production and long-term storage (∼1 year at 4°C).

The objective of this study was to evaluate the individual and synergic effects of the application of Biochar (B), Humic Substances (HS), and Gypsum (G) on the soil properties of a saline–sodic soil, and plant growth and seed quality (polyphenols, protein and yield) of quinoa. Treatments included (B) 22 t ha⁻¹, (HS) 5 kg ha⁻¹, and (G) 47.7 t ha⁻¹. Two quinoa genotypes from Arid Zones (AZ-51 and AZ-103) were selected and established in eight treatments. The B + HS + G combined treatment resulted in increases in root biomass of 206% and 176% in AZ-51 and AZ-103, respectively. Furthermore, electrical conductivity (ECe), sodium adsorption ratio (SAR), and exchangeable sodium percentage (ESP) decreased significantly in all treated soils. When compared to the control, ESP decreased 11-fold in the G treatment, and 9–13-fold in the B + G; B + HS; and B + HS + G treatments. Similarly, soil microbial biomass increased 112% and 322% in the B + HS + G treatment in AZ-51 and AZ-103 genotypes, respectively. Therefore, it can be concluded that the application of combined amendments (B + HS + G) represents an alternative for reclaiming degraded soils, including saline–sodic soils.