Soil sample A: control, without LDPE powder
Five soil cores were taken from each plot and homogenised by hand to obtain a representative sample. After collection, samples were passed through a 2 mm sieve and subsequently transferred to a -80C freezer for pre-extraction storage. Genomic DNA was extracted by mechanical lysis from 0.25 g soil per sample. Quality and concentration of extracted DNA were assessed by agarose gel electrophoresis. Libraries of 16S rRNA gene amplicons were created using primers for rRNA marker genes, specifically for the V4 region of the 16S rDNA targeting bacteria and archaea. PCR were performed using a ViiA7 qPCR system. Thermocycling conditions were: initial denaturation at 95C for 3 min, followed by 8 cycles of 95C for 45 s, 55C for 30 s, and 72C for 30 s with a final elongation at 72C for 5 min. Final pool was run on Illumina MiSeq platform.