DNA extraction
DNA was extracted from ethanol-fixed haemolymph and tissue samples using
DNeasy Blood and Tissue Kit (Qiagen). Haemocyte pellet was obtained by
spinning the cells down with 1400 × g speed for 10 min. After lysis of
tissues, P3 Buffer (Qiagen) was added to precipitate out polysaccharides
that inhibit PCR reactions. Further extraction was performed in
accordance with the protocol provided by manufacturer.