DNA extraction
DNA was extracted from the surface sterilized beetle samples (parental adults, larvae, pupae, and teneral adults) and infested and intact phloem. Although we were focused on intestinal microbiota, we isolated DNA from the whole individuals not directly from guts as the softness of pupal bodies impede such manipulation. DNA was extracted following the phenol-chloroform protocol (Sagova-Mareckova et al., 2008) using the phenol-chloroform–isoamyl alcohol (25:24:1) premixed solution (Sigma-Aldrich, St. Louis, Missouri, USA). The initial homogenization was done on FastPrep-24™ 5G Instrument (Irvine, California, USA) using wolfram beads in combination with glass beads (BioSpec Products, Inc., Bartlesville USA). DNA yield was quantified on Qubit 2.0 Fluorometer (Thermo Fisher Scientific, Waltham, Massachusetts, USA) using Qubit dsDNA BR Assay Kit and DNA quality was checked on Nanodrop (NanoDrop™ 2000c, ThermoFisher scientific).