DNA recovery from hemp stems for retting microbial community investigation. Soil and hemp stem samples

The industrial hemp plant "Cannabis sativa" is a source of vegetable fiber for both textiles and bio-composites applications. After harvesting, the plant stems are laid out on the ground and colonized by micro-organisms (bacteria and fungi) naturally present in the soil and on the stems. To investigate temporal dynamics of retting microbial communities (density levels, diversity, and structure), a reliable protocol for extracting genomic DNA from stems is mandatory. However, very little attention has been paid to the methodological aspects of nucleic acid extraction, although they are crucial for the significance of the final result. Three protocols were selected and tested. A comparative analysis was carried out on soil and two different varieties of hemp stems. The efficiency of each method was measured by evaluating both quantity and quality of the extracted DNA, and abundance and taxonomy of bacterial and fungal populations.