Figure 5. PCR analysis of several genes in tetracycline-treated adult rice weevils. At several times of rearing rice weevils on a diet containing tetracycline (see Materials and Methods), PCR was used to detect 4 genes: the 16S-rRNA genes in Wolbachia and in the principal endosymbiont (SOPE), rice weevil polygalacturonase, and the 18S-rRNA gene of S. oyrzae. Lane 1 is a control from insects reared on wheat flour not supplemented with tetracycline. Lanes 2, 3, 4, 5 and 6 correspond to samples taken after 2, 4, 5, 6 and 7 weeks, respectively, of feeding on tetracycline-supplemented wheat flour.