Extraction methods for pollen metabarcoding

For the construction of plant-pollinator networks, metabarcoding of pollen collections has recently been suggested to offer a number of advantages over traditional methods, but to what extent DNA yield and subsequent diversity and community analyses depend on extraction method remains unclear, especially in insects that carry low pollen loads. Using dilution series of two pollen mixtures (a mock community and pooled natural pollen loads from bumblebees), we compared the effect of three extraction methods (simple mechanical homogenization, a magnetic bead DNA extraction kit and a spin column DNA extraction kit) on pollen richness and community composition.