A SIMPLE TECHNIQUE FOR INDEXING THE MATING STATUS OF MALE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

1986 ◽  
Vol 118 (1) ◽  
pp. 37-41 ◽  
Author(s):  
J.C. Bergh ◽  
W.D. Seabrook
Keyword(s):  
Simple Technique ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Reliable Index ◽  
Mating Status ◽  
Yellow Substance ◽  
Laboratory Colony ◽  
Unmated Male

AbstractSection 7 of the primary simplex of the ductus ejaculatorius of unmated male spruce bud worm moths, Choristoneura fumiferana, contains a yellow substance that is not present in recently mated males. The yellow substance occurs in laboratory-colony males reared on diet and in feral males reared on foliage. It is shown that the presence/absence of this material is a reliable index of copulation during the previous 24 h. Although the yellow substance regenerates over a period of several days, males 0–72 h post-copulation may be indexed when compared with unmated males of similar age.

THE MATING STATUS OF SPRUCE BUDWORM MALES, CHORISTONEURA FUMIFERANA (CLEM.) (LEPIDOPTERA: TORTRICIDAE), CAUGHT IN PHEROMONE-BAITED TRAPS

1986 ◽  
Vol 21 (3) ◽  
pp. 254-262 ◽  
Author(s):  
J. Chris Bergh ◽  
William D. Seabrook
Keyword(s):  
Choristoneura Fumiferana ◽  
Ejaculatory Duct ◽  
Spruce Budworm ◽  
Sampling Period ◽  
Male Mating ◽  
Mating Status ◽  
Mating History ◽  
Baited Traps ◽  
Significant Difference ◽  
Flight Season

The mating status of recently-mated male spruce budworm moths, Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae), caught in traps baited with five different treatments was indexed. During two sampling periods at two test sites both virgin and mated C. fumiferana males were trapped. Significantly more unmated males were captured early in the flight season. There was no significant difference between the proportion of mated and unmated males caught near the end of the flight season. Within sampling periods and sites there were not significant differences among treatments in the proportion of mated males captured nor were these proportions significantly different within sampling periods and between sites. Within sites and between sampling periods the proportion of mated males captured was significantly different, with more mated males being trapped during the later sampling period. The four lepidopteran species for which methodologies have been developed for indexing male mating status are compared with respect to the nature and behaviour of the colored ejaculatory duct fluids that are used as markers of mating history. Current limitations of the method are discussed and possible solutions to these are suggested.

THE MATING STATUS OF FIELD-COLLECTED MALE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEM.) (LEPIDOPTERA: TORTRICIDAE), IN RELATION TO TRAP LOCATION, SAMPLING METHOD, SAMPLING DATE, AND ADULT EMERGENCE

1988 ◽  
Vol 120 (8-9) ◽  
pp. 821-830 ◽  
Author(s):  
J.C. Bergh ◽  
E.S. Eveleigh ◽  
W.D. Seabrook
Keyword(s):  
Sampling Method ◽  
Choristoneura Fumiferana ◽  
Adult Emergence ◽  
Spruce Budworm ◽  
Mate Location ◽  
Mating Status ◽  
Baited Traps ◽  
Trap Location ◽  
Flight Season

AbstractMale spruce budworm moths, Choristoneura fumiferana (Clem.), were captured in 1986 and 1987 and the proportion recently mated was determined for each sample. Mating status was examined in relation to trap location, sampling method, sampling date, and adult emergence. On a given day the proportion of recently mated males captured was similar among pheromone-baited traps both within and among test sites. The number of males trapped increased with increasing trap elevation, although there was no difference in the proportion of mated males at each elevation. Males exhibiting “mate-location behaviour” were captured individually with an insect net and were found to be mated in the same proportion as those caught in pheromone-baited traps. The proportion of recently mated males trapped tended to increase during the early part of the flight season, to fluctuate during the middle portion, and then to decline toward the end of the season. This pattern was due, in part, to adult emergence trends.

Identification of cocoons of Apanteles and Dolichogenidea (Hymenoptera: Braconidae) species attacking Choristoneura fumiferana (Lepidoptera: Tortricidae) and associated Microlepidoptera

2003 ◽  
Vol 135 (5) ◽  
pp. 677-684 ◽  
Author(s):  
Eldon S. Eveleigh ◽  
Steven J. Pollock ◽  
Henri Goulet ◽  
John Huber
Keyword(s):  
Banding Pattern ◽  
Simple Technique ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Identification Key ◽  
Ecological Problems ◽  
Unique Banding Pattern

AbstractWe examined the cocoons of six species of the genera Apanteles and Dolichogenidea attacking spruce budworm, Choristoneura fumiferana Clemens, and Microlepidoptera in the same microhabitat in an effort to overcome taxonomic and ecological problems associated with the identification of these species when adults fail to emerge from their cocoons. Neither cocoon length nor width nor ratio of length to width could be used to identify the six species, owing to considerable overlap in these attributes among the species and the effects of the source of the cocoons. Using a simple technique to examine webbing characteristics of the cocoons, however, we found that each species has a unique banding pattern, determined by the manner in which the density of the webbing varies along the length of the cocoon. This pattern can be used to reliably identify each species. We describe and illustrate the webbing characteristics of each species and provide an identification key based on these characteristics.

scholarly journals Influence of a Foliar Endophyte and Budburst Phenology on Survival of Wild and Laboratory-Reared Eastern Spruce Budworm, Choristoneura fumiferana on White Spruce (Picea glauca)

Forests ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 503 ◽  
Author(s):  
Dan Quiring ◽  
Greg Adams ◽  
Leah Flaherty ◽  
Andrew McCartney ◽  
J. David Miller ◽  
...  
Keyword(s):  
Field Study ◽  
Wild Population ◽  
Choristoneura Fumiferana ◽  
Insect Pest ◽  
Intervention Strategy ◽  
Adult Emergence ◽  
Spruce Budworm ◽  
White Spruce ◽  
Eastern Spruce Budworm ◽  
Laboratory Colony

A manipulative field study was carried out to determine whether the foliar endophyte fungus, Phialocephala scopiformis DAOM 229536, decreased the performance of eastern spruce budworm, Choristoneura fumiferana larvae developing on white spruce trees. Overwintered second-instar budworm larvae from a laboratory colony or from a wild population were placed on endophyte positive or negative trees one or two weeks before budburst. The presence of the endophyte in the needles reduced the survival of C. fumiferana from both a wild population and a laboratory colony. Survival for budworm juveniles up to pupation and to adult emergence was 13% and 17% lower, respectively, on endophyte positive trees. The endophyte did not influence the size or sex of survivors and budworm survival was not influenced by any two- or three-way interactions. Budworm survival was higher for wild than for laboratory-reared budworm and for budworm placed on trees a week before budburst. This may be the first field study to demonstrate the efficacy of an endophytic fungus against wild individuals of a major forest insect pest. The efficacy of the endophyte at low larval densities suggests that it could be a useful tactic to limit spruce budworm population growth in the context of an early intervention strategy.

Geographic variation in susceptibility of the spruce budworm,Choristoneura fumiferana(Lepidoptera: Tortricidae), toBacillus thuringiensisssp. kurstaki is limited

1996 ◽  
Vol 74 (10) ◽  
pp. 1943-1946
Author(s):  
Kees van Frankenhuyzen ◽  
Debbie Gauthier ◽  
John Dedes
Keyword(s):  
Geographic Variation ◽  
Prince Edward Island ◽  
Choristoneura Fumiferana ◽  
Internal Standard ◽  
Spruce Budworm ◽  
Instar Larva ◽  
Probit Regression ◽  
Forest Protection ◽  
Susceptible Population ◽  
Laboratory Colony

Geographic variation in susceptibility to the pathogen Bacillus thuringiensis Berliner ssp. kurstaki was assessed among five populations of the spruce budworm, Choristoneura fumiferana (Clemens), across Canada. Larvae or pupae were collected from Prince Edward Island, northern New Brunswick, central Ontario, northeastern Alberta, and northeastern British Columbia. The response of field populations to the 1980 industrial standard of the HD-1 strain of the pathogen was compared with the concurrent response of a laboratory colony as an internal standard. Equal slopes of the probit regression lines indicated homogeneity of variation in susceptibility among populations. LC50values ranged from 2.6 international units (IU) per sixth-instar larva for the most susceptible population to 8.3 IU per larva for the least susceptible. Although significant, the variation in population susceptibility was within the range of variation that is commonly observed among repeated bioassays against cohorts of a single population. We conclude that variation in susceptibility to B. thuringiensis among spruce budworm populations is low. The data provide a basis for monitoring changes in susceptibility of spruce budworm populations in response to increased use of this pathogen in forest-protection programs.

CARPENTER ANTS AS PREDATORS OF SPRUCE BUDWORM IN THE BOREAL FOREST OF NORTHWESTERN ONTARIO

1992 ◽  
Vol 124 (6) ◽  
pp. 1093-1100 ◽  
Author(s):  
C.J. Sanders ◽  
A. Pang
Keyword(s):  
Boreal Forest ◽  
Boreal Forests ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Western North America ◽  
Tree Crown ◽  
Carpenter Ants ◽  
Northwestern Ontario ◽  
Large Numbers ◽  
Laboratory Colony

AbstractIn the boreal forest of northwestern Ontario, where carpenter ants (Camponotus spp.) construct extensive underground tunnels, few worker ants were seen on the aerial portions of trees containing colonies of the ants or on neighboring trees, even though the trees were infested by large numbers of spruce budworm [Choristoneura fumiferana (Clem.)] larvae. Immunochemical techniques detected less spruce budworm soluble protein in worker ants from this area than in a laboratory colony that had been fed budworm larvae, or in a colony located in a spruce tree that was surrounded by gravel where the ants were unable to build underground tunnels and instead foraged extensively in the tree crown. This suggests that, in contrast to evidence from western North America, carpenter ants in the boreal forests of northwestern Ontario, and perhaps elsewhere throughout the range of the spruce budworm, are of limited importance as predators of the spruce budworm.

Derivation of Pheromone-Based Larval Thresholds in Spruce Budworm Accounting for Distance to Defoliated Forest Stands

2021 ◽  
Author(s):  
Marc Rhainds ◽  
Ian DeMerchant ◽  
Pierre Therrien
Keyword(s):  
Boreal Forests ◽  
Large Scale ◽  
Choristoneura Fumiferana ◽  
Intervention Strategy ◽  
Spruce Budworm ◽  
Interactive Effects ◽  
The Novel ◽  
Forest Stands ◽  
General Guideline ◽  
Number Of Males

Abstract Spruce budworm, Choristoneura fumiferana Clem. (Lepidoptera: Tortricidae), is the most severe defoliator of Pinaceae in Nearctic boreal forests. Three tools widely used to guide large-scale management decisions (year-to-year defoliation maps; density of overwintering second instars [L2]; number of males at pheromone traps) were integrated to derive pheromone-based thresholds corresponding to specific intergenerational transitions in larval densities (L2i → L2i+1), taking into account the novel finding that threshold estimates decline with distance to defoliated forest stands (DIST). Estimates of thresholds were highly variable between years, both numerically and in terms of interactive effects of L2i and DIST, which limit their heuristic value. In the context of early intervention strategy (L2i+1 > 6.5 individuals per branch), however, thresholds fluctuated within relatively narrow intervals across wide ranges of L2i and DIST, and values of 40–200 males per trap may thus be used as general guideline.

Weather and Outbreaks of the Spruce Budworm in the Province of Quebec from 1939 to 1956

1961 ◽  
Vol 93 (2) ◽  
pp. 118-123 ◽  
Author(s):  
J. G. Pilon ◽  
J. R. Blais
Keyword(s):  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
The Past ◽  
Forest Regions ◽  
Tree Component ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula

Nearly all forest regions in the Province of Quebec where balsam fir (Abies balsamea (L.) Mill.) is an important tree component have been subjected to severe defoliation by the spruce budworm, Choristoneura fumiferana (Clem.), during the past 20 years. These outbreaks have followed an easterly direction beginning near the Ontario-Quebec border in 1939 and ending in the Gaspé Peninsula in 1958.

GROUND RELEASES OF TRICHOGRAMMA MINUTUM RILEY (HYMENOPTERA: TRICHOGRAMMATIDAE) AGAINST THE SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE)

1987 ◽  
Vol 119 (3) ◽  
pp. 251-263 ◽  
Author(s):  
S.M. Smith ◽  
M. Hubbes ◽  
J.R. Carrow
Keyword(s):  
Optimal Strategy ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Egg Mass ◽  
Northern Ontario ◽  
Inundative Release ◽  
Egg Masses ◽  
Trichogramma Minutum ◽  
Spruce Stands ◽  
Natural Parasitism

AbstractDuring 1982 and 1984, ground releases of Trichogramma minutum Riley were assessed for control of the spruce budworm, Choristoneura fumiferana (Clemens), on 12- to 20-year-old, white spruce stands in northern Ontario. Maximum parasitism of susceptible egg masses was 16 and 87% following the release of 480 000 and 12 million female T. minutum per hectare, respectively. Releases at intervals of 1 week maintained parasitism of susceptible egg masses at constant levels throughout the oviposition period of spruce budworm. When parasitism of susceptible egg masses was maintained above 78.2% during the ovipositional period, total egg mass parasitism averaged 58.0% and resulted in an 80.3% reduction of overwintering 2nd-instar larvae. The optimal strategy for reducing spruce budworm was two releases of T. minutum at an interval of 1 week in the ovipositional period. This allowed a second generation of parasitoids to emerge from the spruce budworm eggs that were more efficient in maintaining high levels of parasitism than those emerging from the standard rearing host. Natural parasitism of spruce budworm egg masses was less than 4% and there was no carryover of parasitism in the years following inundative release. The rate of T. minutum release necessary to achieve effective mortality of spruce budworm during outbreak populations is discussed briefly.

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