Submitted to: National Entomological Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2001
Publication Date: N/A
Technical Abstract: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing analysis of the nuclear ribosomal ITS1 region was used to examine genetic variation in local and dispersed geographical populations of northern corn rootworm, Diabrotica barberi (NCR). NCR populations from 10 States were examined. Sequencing of the 645-646 bp amplicon revealed four polymorphic sites. PCR-RFLP analysis of 312 beetles from 38 samples sites with the restriction enzyme Bcl I, detected three genotypes. Many beetles had heterogeneity at a nucleotide site recognized by Bcl I, which was supported by DNA sequence data. Populations east of Illinois were homogeneous for one genotype, two genotypes were observed in Illinois, Wisconsin and North Dakota, while South Dakota, Nebraska, Iowa, and Kansas populations were composed of all three genotypes. There appears to be a phylogeographic pattern of genetic diversity, which may be related to the occurrence of the endosymbiont, Wolbachia. Observed genetic demarcation is relevant given the impending release of B. t. genetically modified corn developed for the control of corn rootworms.