Assessment of the Systems Approach for the Phytosanitary Treatment of Wood Infested With Wood-Boring Insects.

Addressing the risk from pests present in wood and wood products destined for international trade is an essential step towards minimizing the movement, introduction and establishment of invasive species. One method of managing the pest risk associated with wood commodities is the use of a systems approach that incorporates multiple independent measures applied along a production pathway. However, quantifying the reduction of risk can be difficult because the approach requires raw material infested with the pest of interest at a sufficient density to be able to quantify changes in pest abundance. We tested a systems approach for the production of sawn wood using green ash, Fraxinus pennsylvanica Marshall (Lamiales: Oleaceae), infested with emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), by quantifying the change in pest density during the milling process and the precise effect of heat treatment on insects in situ. Greater than 90% of emerald ash borer were removed at the first step of the milling process (debarking) and >99% were removed before the production of green sawn wood. No insects survived kilning or heat treatment. All life stages of emerald ash borer were killed at 56°C and above. Heat, however, had no sublethal effect on emerald ash borer performance. These results show that the application of a systems approach to mitigate emerald ash borer in heat-treated, sawn wood is effective. Moreover, the model-system approach developed in this study can be a template for investigating the effect of systems approaches for other phloem-feeding insects.

A comprehensive DNA barcode library for the looper moths (Lepidoptera: Geometridae) of British Columbia, Canada.

BACKGROUND: The construction of comprehensive reference libraries is essential to foster the development of DNA barcoding as a tool for monitoring biodiversity and detecting invasive species. The looper moths of British Columbia (BC), Canada present a challenging case for species discrimination via DNA barcoding due to their considerable diversity and limited taxonomic maturity. METHODOLOGY/PRINCIPAL FINDINGS: By analyzing specimens held in national and regional natural history collections, we assemble barcode records from representatives of 400 species from BC and surrounding provinces, territories and states. Sequence variation in the barcode region unambiguously discriminates over 93% of these 400 geometrid species. However, a final estimate of resolution success awaits detailed taxonomic analysis of 48 species where patterns of barcode variation suggest cases of cryptic species, unrecognized synonymy as well as young species. CONCLUSIONS/SIGNIFICANCE: A catalog of these taxa meriting further taxonomic investigation is presented as well as the supplemental information needed to facilitate these investigations.

Towards a global barcode library for Lymantria (Lepidoptera: Lymantriinae) tussock moths of biosecurity concern.

BACKGROUND: Detecting and controlling the movements of invasive species, such as insect pests, relies upon rapid and accurate species identification in order to initiate containment procedures by the appropriate authorities. Many species in the tussock moth genus Lymantria are significant forestry pests, including the gypsy moth Lymantria dispar L., and consequently have been a focus for the development of molecular diagnostic tools to assist in identifying species and source populations. In this study we expand the taxonomic and geographic coverage of the DNA barcode reference library, and further test the utility of this diagnostic method, both for species/subspecies assignment and for determination of geographic provenance of populations. METHODOLOGY/PRINCIPAL FINDINGS: Cytochrome oxidase I (COI) barcodes were obtained from 518 individuals and 36 species of Lymantria, including sequences assembled and generated from previous studies, vouchered material in public collections, and intercepted specimens obtained from surveillance programs in Canada. A maximum likelihood tree was constructed, revealing high bootstrap support for 90% of species clusters. Bayesian species assignment was also tested, and resulted in correct assignment to species and subspecies in all instances. The performance of barcoding was also compared against the commonly employed NB restriction digest system (also based on COI); while the latter is informative for discriminating gypsy moth subspecies, COI barcode sequences provide greater resolution and generality by encompassing a greater number of haplotypes across all Lymantria species, none shared between species. CONCLUSIONS/SIGNIFICANCE: This study demonstrates the efficacy of DNA barcodes for diagnosing species of Lymantria and reinforces the view that the approach is an under-utilized resource with substantial potential for biosecurity and surveillance. Biomonitoring agencies currently employing the NB restriction digest system would gather more information by transitioning to the use of DNA barcoding, a change which could be made relatively seamlessly as the same gene region underlies both protocols.

Ophiostomatoid fungi associated with the northern spruce engraver, Ips perturbatus, in western Canada.

A number of ophiostomatoid fungi were isolated from the spruce-infesting bark beetle, Ips perturbatus and its galleries collected from felled spruce trees and logs in northern BC and the Yukon Territory. Isolates were identified to species using morphological characteristics, nuclear ribosomal DNA and partial beta-tubulin gene sequences. Thirteen morphological and phylogenetic species were identified among the isolates. Leptographium fruticetum, Leptographium abietinum, Ophiostoma bicolor, Ophiostoma manitobense, O. piceaperdum, and eight undescribed species of the genus Ophiostoma and the anamorph genera Leptographium, Hyalorhinocladiella, Ambrosiella and Graphium. A number of these species, i.e. L. fruticetum, Hyalorhinocladiella sp. 2, O. bicolor and O. manitobense, were isolated repeatedly from I. perturbatus, while others, i.e. Graphium sp. 1 and O. piceaperdum, seemed to be sporadic associates. Among all the isolates, L. fruticetum had the highest relative dominance in this survey. A high frequency of occurrence of this species with the beetle may indicate a specific relationship between the two partners.