Diets combining the eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) with corn pollen, green snap bean pods, and adult western flower thrips [Frankliniella occidentalis Pergrande (Thysanoptera: Thripidae)] were evaluated for their effects on the predatory anthocorid bug Orius insidiosus (Say). Nymphs fed only corn pollen did not complete development. Fourteen percent of the nymphs fed only green bean pod sections reached the adult stage. Females reared on a diet of bean pod sections did not oviposit. Nymphal survival, adult longevity, and fecundity were greatest for diets containing both E. kuehniella and green bean pods. When diets of bean pod sections and eggs of E. kuehniella were supplemented with pollen, egg production was slightly increased. Adult females provided with thrips were not more fecund than females maintained on a diet of eggs of E. kuehniella. Egg production increased significantly with the number of thrips consumed, demonstrating the importance of adult nutrition.

The life cycle, phenology, and abundance of Epuraea obliquus Hatch was studied near Hinton, Alberta. Most of the life cycle occurs on galls of Endocronartium harknessii (J.P. Moore) Y. Hiratsuka (western gall rust) infecting lodgepole pine (Pinus contorta Dougl. var latifolia Engelm.). Both adults and larvae feed on the spores of the fungus. Individuals of this beetle were found on most galls sampled. Adults overwinter in the soil. They emerge in the spring to seek out and colonize galls. Eggs are laid on the surface of galls, mainly under the periderm, and larvae feed on the fungus, developing through three larval instars. Larvae in the last instar drop from galls to pupate in the soil. Adults leave the soil in late summer and return to feed on inactive galls before overwintering in the soil. The phenology of E. obliquus is closely synchronized with the timing of rust sporulation and the impact of beetle feeding may be an important natural control of western gall rust.

Eggs of blueberry leaftier, Croesia curvalana (Kearfott), were transferred from outdoors at 15-day intervals from 15 November to 1 March and held in the laboratory at 20°C, 16L:8D. Mean hatching time continually decreased with each successive transfer date and was significantly shorter for eggs transferred on 1 March compared with any previous transfer date. Transfer date also had a significant effect on percentage hatch, which generally increased with longer exposure of eggs to outdoor conditions. Mean hatching time was longer under 10L:14D photoperiod than at 13L:11D or 16L:8D conditions at all three temperatures studied. Rate of postdiapause development was linearly related to constant temperatures in the range from 6 to 25°C, but appeared to have deviated from linearity at 30°C. The lower threshold temperature for postdiapause development of eggs was estimated to be 3.4°C. Means of 60, 77, and 97 degree-days above a lower threshold of 3.5°C were required for hatching of the 10th, median, and 90th percentile of eggs under laboratory conditions, respectively. In each of 3 years, eclosion of first-instar larvae occurred over a 10- to 17-day period in late April to mid-May. Degree-day accumulations based on litter temperatures in the field predicted the dates of 10th, 50th and 90th percentile eclosion of first-instar larvae within ±2 days of the observed dates.

Attack and emergence of the engraver beetles Ips pini Say and I. latidens LeConte were measured in lodgepole pine (Pinus contorta var. latifolia Engelm.) naturally attacked by the mountain pine beetle, Dendroctonus ponderosae Hopk., in 1991. Sample trees were baited with the Ips pheromones ipsdienol and lanierone 1 week and 3 weeks after attack by the mountain pine beetle and again the following spring to observe the effects of the timing of bait placement. The densities of attack, egg gallery length, emergence, and hibernation of Ips species were measured. Ips latidens did not attack either the baited or unbaked trees at breast height until the spring of 1992 and the relatively low emergence was not significantly different by treatments. Among the 1991 treatments, the densities at breast height (1.3 m) of I. pini attack, egg gallery length, adult emergence in the fall of 1991, and numbers of hibernating adults in the duff were all highest for the 3-week treatment and lowest for the unbaked treatment. Significantly higher densities of beetles emerged and hibernated in the duff on the north sides of trees. Ips pini emergence in late summer 1992 from trees additionally baited in spring 1992 was significantly higher than for trees baited only in fall 1991. The density and temporal distribution of the emergence of both Ips species is discussed in relation to that of the mountain pine beetle.

Variability in vectoring efficiency among six clones of Rhopalosiphum padi L. and five clones of Sitobion avenae Fabr. in transmission of three French PAV isolates (PAV-RG, PAV-2t, and PAV-13t) of barley yellow dwarf viruses (BYDVs) on seedlings of barley (Hordeum vulgare L.) cv. Plaisant was determined. All the clones could transmit these three isolates, but their vectoring efficiency was significantly different: 91% and 56% transmission efficiencies were obtained from the most efficient clones (Rp-M and Sa-R1) but only 21% and 9% from the least efficient clones (Rp-R26 and Sa-V) with 5-day acquisition and inoculation access periods (AAP, IAP). A significant difference in overall transmission between apterous adults and winged aphids of the tested clones was also found. In most cases, apterous adults were more efficient than were winged aphids. The overall transmission efficiency of apterous adults was 1.5 and 1.7 times that of winged ones for R. padi and S. avenae, respectively. The transmissibility of PAV-RG and PAV-2t isolates was similar within each of the tested aphid clones, but that of the PAV-13t isolate differed, particularly for the poorly efficient vector clones of S. avenae. Temperature could significantly influence the vectoring efficiency of the tested clones of R. padi, but the influence was greater on Rp-R26. High temperature (25 °C) facilitated more transmission than did low temperature (14 °C), and high temperature for AAP played a more important role than it did for IAP.

Collections (68) of spruce budworm from 33 locations from Newfoundland to Alaska were analysed for isozyme frequencies using horizontal starch gels. Collections represented pre-, early-, mid-, late-, and post-outbreak stages of several populations in balsam fir, white spruce, and mixed host forests, as well as successive annual collections at several locations. Isozymes were measured at 11 loci in mature larvae and at six loci in pheromone-trapped males; frequencies were essentially the same in both stages, and from all host species. Three loci (IDH-2, LDH-1, and AAT-1) were found to be sex-linked, with no heterozygotes in females. Mean percentage heterozygosity ranged from 13.2 to 23.1; at individual locations it tended to decrease over successive years of outbreak and over successive collections in the same year. Contingency chi-square analysis indicated small differences related to location and outbreak history but all populations were generally homogeneous over the entire range. Nevertheless, one allozyme of AAT-1 exhibited a significant cline in frequency from the southeast to the northwest. Gene flow across the entire range appeared to be appreciable.

Allozymes at several polymorphic loci were assayed in larval collections of 12 recognized species and two possible new species of Choristoneura and two species of Archips. Most of the 48 collections came from high density populations, and those of C. fumiferana, C. occidentalis, and C. pinus represented much of the geographic range of these species. Mean percentage heterozygosity ranged from 2.0 to 18.6%, based on nine polymorphic loci. Three loci are sex-linked in C. fumiferana, two in C. pinus and C. occidentalis and probably in some other members of the group. Allozymes of aspartate transaminase (AAT-1) were most varied among the species and permit identification of individual C. fumiferana in better than 95% of cases. Among the group of coniferophagous Choristoneura species genetic distances were small (max. Nei = 0.232); C. fumiferana was the most distinct species. Wagner trees based on modified Rogers’ distances supported the above conclusions but indicated that separations among C. biennis, C. orae, C. occidentalis, C. carnana, C. subretiniana, and the two new species of Choristoneura were very small and probably below the species level, based on the allozymes measured.

Adding queen mandibular pheromone into honey bee colonies earlier than 24 h after queen loss resulted in an inhibition of queen-rearing, but not when added after 4 days. The number of queen cells initiated in each treatment decreased with the addition of the pheromone, although there were no effects on the number of queen cells torn down following pheromone treatment. The effect of adding the pheromone to queenless colonies given newly hatched female larvae under different regimens of queen cell provisioning and cell structure also was investigated. Only colonies in which larvae were presented in unmodified worker comb exhibited significantly lower rates of queen-rearing. Results indicate that queen mandibular pheromone inhibits the initiation of queen-rearing but not the maintenance of established cells.

The genus Paratelenomus Dodd is revised from a worldwide perspective. Three species are described as new: P. angor [Taiwan, Thailand], P. indivisus [Papua New Guinea, Australia], and P. matinalis [Vanuatu]. Paratelenomus bicolor (Dodd) [Australia], P. saccharalis (Dodd) [southern Europe, Africa, tropical Asia, Australia], P. ophiusa (Dodd) [Papua New Guinea, Australia], P. striativentris (Risbec) [Africa, India], and P. tetartus [Indonesia, Malaysia, Philippines] are redescribed. Aphanurus graeffei Kieffer, 1917 and Asolcus minor Watanabe, 1954 are junior synonyms of P. saccharalis (Dodd), 1913. An identification key to species is provided. The relationship of Paratelenomus within Telenominae is discussed; the hypothesized sister group is Nirupama Nixon.

A systematic revision of North American species of the genus Ameletus, excluding parthenogenetic species, is presented. Seven new species are described (A. andersoni, A. bellulus, A. doddsianus, A. edmundsi, A. majusculus, A. pritchardi, and A. tolae), separate keys are given to western and eastern species, annotated accounts of all 30 presently recognized bisexual species are provided, taxonomic characters are illustrated, and distribution data are presented for all species. The following nomenclatural changes are proposed: Ameletus aequivocus is considered a junior synonym of A. sparsatus; A. alticolus and A. celeroides junior synonyms of A. celer; A. connectina and A. connectus junior synonyms of A. velox; A. facilis a junior synonym of A. vancouverensis; A. monta a junior synonym of A. similior; A. querulus a junior synonym of A. shepherdi. The specific status of A. tuberculatus is questioned and it is provisionally considered to be the same as A. celer.

While conducting research on the geographic origin of the wheat stem sawfly (Cephus cinctus Norton), we compared North American specimens to specimens of Eurasian Cephus spp., and discovered that specimens currently placed as C. hyalinatus Konow from Siberia are conspecific with the North American species. Given the pest status of the North American populations, which attack wheat and other cereals in the upper Great Plains (Weiss and Morrill 1992), this discovery has important implications for the management of the species. Discussion of these implications will be provided elsewhere (Ivie 1996).

The addition of legumes in the small grain cropping system of the western prairie regions of North America has several advantages: an increased diversity in the landscape may reduce pest loads of insects, plant pathogens, and weeds; a decreased financial risk for producers by diversifying the types of crops produced; and increased soil nitrogen via fixation and mineralization. Several alternative legumes are being examined for potential production in this region, including lupins (Lupinus spp.), faba bean (Vicia faba L.), chickpea (Cicer arietinum L.), and lentil (Lens culinaris Medikus).

The cabbage maggot, Delia radicum (L.), is a major root-infesting pest of cruciferous crops (Davidson and Lyon 1979). Current control methods include soil drenches with fensulfothion, carbofuran, and chlopyrifos (Matthews-Geringer and Hough-Goldstein 1988). Partial deterrency of oviposition by cabbage maggots was achieved using turpentinesoaked stakes (Havukkala 1982), and 3,5-dimethoxy-4-hydroxycinnamica cid, produced in the frass of a lepidopteran pest of cabbage (Jones et al. 1988). A blend of three monoterpenes (3-carene, limonene, and p-cymene) was found by Ntiamoah et al. (1996) to be the major oviposition deterrent for the onion maggot, Delia antiqua (Meigen), in a commercial pine oil, Norpine 65 (Northwest Petrochemicals, Annacortes, Washington). Our objectives were to evaluate this blend, and a more complex blend containing three additional constituents, as oviposition deterrents in the laboratory for the cabbage maggot.

Detoxicative enzyme systems, such as the cytochrome P450 monooxygenases, gluthione S-transferases, and general esterases, have been widely studied in holometabolous insects (e.g. Lepidoptera, Diptera, and Coleoptera). These, and other enzyme systems, play important roles in insecticide resistance, but are also important in insect–host plant relationships, because host range can partially depend on the ability of an insect to cope with putatively toxic allelochemicals in an otherwise suitable host plant (e.g. Lindroth 1989). In some cases, differences in the relative activities of these enzymes between closely related insect taxa can have significant biological consequences (Siegfried and Mullin 1989).