Submitted to: Corn Rootworm Areawide Management Program
Publication Type: Proceedings
Publication Acceptance Date: November 5, 1999
Publication Date: N/A
Technical Abstract: Research has continued to examine genetic differentiation among economically important Diabrotica species. The overall goals include gathering requisite fundamental molecular genetic knowledge about Diabrotica sp., to survey population diversity and help clarify the biosystematics, and to develop molecular marker systems for identifying species/strains of Diabrotica and emerging phenotypes. The two areas of emphasis this year have been: (1) Molecular phylogeny and biosystematics of the pest Diabrotica; (2) Geographic genetic variation in the northern corn rootworm. We have utilized DNA segments from both the nuclear genome and mitochondrial genome. The primary nuclear region has been the nuclear ribosomal internal transcribed spacer 1 (ITS1). Some preliminary work is in progress using the nuclear ribosomal intergenic spacer (IGS). The ITS1 and IGS are being investigated by nucleotide sequencing and restriction site comparisons. For the mitochondrial DNA (mtDNA) nucleotide sequencing of a small region has been used for species comparisons. A much larger portion of the mtDNA has been used for restriction fragment analysis of PCR amplicons (PCR-RFLP). The utility of ribosomal spacers and mtDNA for species and population level analysis is well known.