Phylogeography of the walnut twig beetle, Pityophthorus juglandis, the vector of thousand cankers disease in North American walnut trees.

ABSTRACT: Thousand cankers disease (TCD) of walnut trees (Juglans spp.) results from aggressive feeding in the phloem by the walnut twig beetle (WTB), Pityophthorus juglandis, accompanied by inoculation of its galleries with a pathogenic fungus, Geosmithia morbida. In 1960, WTB was only known from four U.S. counties (in Arizona, California, and New Mexico), but the species has now (2014) invaded over 115 counties, representing much of the western USA, and at least six states in the eastern USA. The eastern expansion places TCD in direct proximity to highly valuable (> $500 billion) native timber stands of eastern black walnut, Juglans nigra. Using mitochondrial DNA sequences, from nearly 1100 individuals, we examined variation among 77 samples of WTB populations across its extended range in the USA,

SUBMITTER: Rugman-Jones PF 

PROVIDER: S-EPMC4335055 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature