Identification of a Fourth Haplotype of Bactericera cockerelli (Hemiptera: Triozidae) in the United States

The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), is a pest of potato and other solanaceous crops in North and Central America and New Zealand. Previous genotyping studies have demonstrated the presence of three different haplotypes of B. cockerelli in the United States corresponding to three geographical regions: Central, Western, and Northwestern. These studies utilized psyllids collected in the western and central United States between 1998 and 2011. In an effort to further genotype potato psyllids collected in the 2012 growing season, a fourth B. cockerelli haplotype was discovered corresponding to the Southwestern United States geographical region. High-resolution melting analyses identified this new haplotype using an amplicon generated from a portion of the B. cockerelli mitochondrial cytochrome coxidase subunit I gene. Sequencing of this gene, as well as use of a restriction enzyme assay, confirmed the identification of the novel B. cockerelli haplotype in the United States.