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In North America Amylostereum areolatum (Chaillet ex Fr.) Boidin is a fungal symbiont associated with both the non-native Sirex noctilio Fabricius (Hymenoptera: Siricidae) and less commonly the native Sirex nigricornis Fabricius (Hymenoptera: Siricidae) woodwasps. The relationship between S. noctilio and A. areolatum constitutes a serious threat to pine plantation in the southern hemisphere. Studies have shown evidence of exchange of symbionts between non-native and native Sirex species. Our objectives were 1) to identify and assemble a panel of rDNA intergenic spacer–single nucleotide polymorphisms (IGS-SNPs) for genotyping strains of A. areolatum symbionts associated with Sirex species in North America, and 2) to develop genetic markers for monitoring the spread of specific A. areolatum haplotypes associated with S. noctilio across regions. The IGS-SNPs panel analyzed included haplotypes B1, B2, D1, D2 (from known IGS type B and D), E, and F. Genetic markers and haplotype-specific primers were designed to detect the IGS haplotypes D and E of A. areolatum. We found that haplotype D was absent in A. areolatum from S. nigricornis in Louisiana, while haplotype E was detected in all A. areolatum from S. nigricornis in Canada and Louisiana. Both haplotype D and E were co-detected in approximately 5% of samples from Canada. The IGS-SNP markers detected specific haplotypes accurately. Observing haplotype D in any A. areolatum from the native S. nigricornis likely indicates the presence of the potentially harmful S. noctilo-A. areolatum complex. The work highlights how IGS-SNPs can help in early detection without direct occurrence/observations of the non-native species of concern.

Tranosema rostrale rostrale (Brishke) (subfamily Campopleginae) is a parasitoid of the eastern spruce budworm, Choristoneura fumiferana (Clemens), in Canada and the United States. T. r. rostrale has often been confused with the closely related Enytus montanus (Ashmead), another parasitoid of C. fumiferana. These 2 species are defined and characters distinguishing them are compared and illustrated. A survey across southern Quebec indicates that >99% of all T. r. rostrale/E. montanus-like parasitoids recovered from spruce budworm larvae implanted in fir stands over a period of 1 wk belong to the former species. T. r. rostrale oviposits in all postdiapause instars of C. fumiferana, as well as in several alternative hosts, starting in late May in the Quebec City region. At 20°C, development inside the host takes 14 d and the parasitoid goes through 3 stadia. T. r. rostrale is believed to complete 2 or 3 additional generations on alternate hosts. Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre, 1055 du PEPS, P.O. Box 3800, Sainte-Foy, QC, Canada G1V 4C7. Eastern Cereal and Oil Seed Research Centre, Agriculture and Agri-Food Canada, Research Branch, Ottawa, ON, Canada K1A 0C6. Departement de biologie, Universite Laval, Sainte-Foy, QC, Canada G1K 7P4.