Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-18T15:03:20.615Z Has data issue: false hasContentIssue false
  • English
  • Français

Seasonal changes in seed reduction in lodgepole pine cones caused by feeding of Leptoglossus occidentalis (Hemiptera: Coreidae)

Published online by Cambridge University Press:  02 April 2012

Ward B. Strong
Ward B. Strong
Affiliation:
British Columbia Ministry of Forests and Range, Kalamalka Forestry Centre, 3401 Reservoir Road, Vernon, British Columbia, Canada V1B 2C7 (e-mail: Ward.Strong@gov.bc.ca)
Get access Rights & Permissions [Opens in a new window]

Abstract

Management of Leptoglossus occidentalis Heidemann in lodgepole pine (Pinus contorta var. latifolia Engelm.) seed orchards of British Columbia, Canada, would be improved with knowledge of its damage potential at different times of the growing season. Mesh insect-exclusion bags were placed over cones, and adults or nymphs of L. occidentalis were enclosed in different bags for 9 periods of 10 to 38 days between 6 May and 17 September 2004. Feeding by adult females between 6 May and 28 May reduced total extractable seeds, a result of ovule damage before fertilization. Reduction in the number of filled seeds per cone was highest between 6 May and 29 June, with each adult female reducing yield by approximately 1.7 seeds per day. Between 29 June and 10 August, each adult female reduced the number of filled seeds per cone (seed set) by 1.0 to 1.25 per day. Seed set reduction declined to approximately 0.25 filled seeds per adult female per day after 10 August. Third to fifth instars caused seed set reduction between 0.6 and 1.2 filled seeds per cone per nymph feeding day from 29 June to 10 August. Utilizing these findings would improve management of L. occidentalis in a commercial seed orchard setting.

Résumé

La gestion des Leptoglossus occidentalis Heidemann dans les pépinières à graines du pin vrillé (Pinus contorta var. latifolia Engelm.) en Colombie-Britannique serait améliorée si on connaissait leur potentiel de dommage à différents moments dans la saison de croissance. Des sacs d'exclusion en filet ont été placés sur les cônes; des adultes ou des larves de L. occidentalis ont été introduits dans des sacs différents durant 9 périodes de 10 à 38 jours entre le 6 mai et le 17 septembre 2004. L'alimentation par les femelles adultes entre le 6 mai et le 28 mai a réduit le nombre total de graines récupérables, à cause du dommage fait aux ovules avant la fécondation. La réduction du nombre de graines pleines par cône est maximale entre le 6 mai et le 29 juin, alors que chaque femelle adulte réduit le rendement par environ 1,7 graine par jour. Entre le 29 juin et le 10 août, chaque femelle adulte réduit les graines pleines de 1,0 à 1,25 graine par jour. La réduction des ensembles de graines diminue à 0,25 graine pleine par adulte femelle par jour après de 10 août. Les larves de troisième à cinquième stades causent une réduction des ensembles de graines de 0,6 à 1,2 graines pleines par jour d'alimentation de larve entre le 29 juin et le 10 août. L'utilisation de ces résultats dans le contexte d'une pépinière à graines commerciale pourrait améliorer la gestion de L. occidentalis.

[Traduit par la Rédaction]

Type
Articles
Information
The Canadian Entomologist , Volume 138 , Issue 6 , December 2006 , pp. 888 - 896
Copyright
Copyright © Entomological Society of Canada 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bates, S.L. 1999. Impact of the western conifer seed bug, Leptoglossus occidentalis Heidemann (Hemiptera: Coreidae), on yield, seed storage reserves and seedling vigour in Douglas-fir. Master of Pest Management thesis, Simon Fraser University, Burnaby, British Columbia.Google Scholar
Bates, S.L. 2002. Detection, impact and management of the western conifer seed bug, Leptoglossus occidentalis (Heteroptera: Coreidae), in lodgepole pine seed orchards. Ph.D. thesis, Simon Fraser University, Burnaby, British Columbia.Google Scholar
Bates, S.L., and Borden, J.H. 2005. Life table for Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae) and prediction of damage in lodgepole pine seed orchards. Agricultural and Forest Entomology, 7: 145–151.Google Scholar
Bates, S.L., Borden, J.H., Kermode, A.R., and Bennett, R.G. 2000. Impact of Leptoglossus occidentalis (Hemiptera: Coreidae) on Douglas-fir seed production. Journal of Economic Entomology, 95: 1444–1451.CrossRefGoogle Scholar
Bates, S.L., Lait, C.G., Borden, J.H., and Kermode, A.R. 2001. Effect of feeding by the western conifer seed bug, Leptoglossus occidentalis,onthe major storage reserves of developing seeds and on seedling vigor of Douglas-fir. Tree Physiology, 21: 481–487.CrossRefGoogle Scholar
Bates, S.L., Lait, C.G., Borden, J.H., and Kermode, A.R. 2002 a. Measuring the impact of Leptoglossus occidentalis (Heteroptera: Coreidae) on seed production in lodgepole pine using an antibody-based assay. Journal of Economic Entomology, 95: 770–777.CrossRefGoogle ScholarPubMed
Bates, S.L., Strong, W.B., and Borden, J.H. 2002 b. Abortion and seed set in lodgepole and western white pine conelets following feeding by Lepto-glossus occidentalis (Heteroptera: Coreidae). Environmental Entomology, 31: 1023–1029.CrossRefGoogle Scholar
Blatt, S.E., and Borden, J.H. 1996. Distribution and impact of Leptoglossus occidentalis Heidemann (Hemiptera: Coreidae) in seed orchards in British Columbia. The Canadian Entomologist, 128: 1065–1076.CrossRefGoogle Scholar
Blatt, S.E., and Borden, J.H. 1998. Interactions between the Douglas-fir seed chalcid, Megastigmus spermotrophus (Hymenoptera: Torymidae), and the western conifer seed bug, Leptoglossus occidentalis (Hemiptera: Coreidae). The Canadian Entomologist, 130: 775–782.CrossRefGoogle Scholar
Connelly, A.E., and Schowalter, T.D. 1991. Seed losses to feeding by Leptoglossus occidentalis (Heteroptera: Coreidae) during two periods of second-year cone development in western white pine. Journal of Economic Entomology, 84: 215–217.CrossRefGoogle Scholar
Hanson, P.D. 1984. Comparison of damage to douglas-fir (Pseudotsugae menziesii (Mirb.) Franco) seed, by each life stage of Leptoglossus occidentalis Heidemann (Hemiptera: Coreidae). B.Sc. (Forestry) thesis, University of British Columbia, Vancouver, British Columbia.Google Scholar
Koerber, T.W. 1963. Leptoglossus occidentalis (Hemiptera: Coreidae), a newly discovered pest of coniferous seed. Annals of the Entomological Society of America, 56: 229–234.CrossRefGoogle Scholar
Krugman, S.L., and Koerber, T.W. 1969. Effect of cone feeding by Leptoglossus occidentalis on ponderosa pine seed development. Forest Science, 15: 104–110.Google Scholar
Lait, C.G., Bates, S.L., Morrissette, K.K., Borden, J.H., and Kermode, A.R. 2001. Biochemical assays for identifying seeds of lodgepole pine and other conifers fed on by Leptoglossus occidentalis Heidemann (Hemiptera: Coreidae). Canadian Journal of Botany, 79: 1349–1357.CrossRefGoogle Scholar
Owens, J.N., and Molder, M. 1984. The reproductive biology of lodgepole pine. British Columbia Ministry of Forests, Information Services Branch, Victoria, British Columbia.Google Scholar
Portlock, F.T. 1996. A field guide to collecting cones of British Columbia conifers. Canadian Forest Service, Victoria, British Columbia.Google Scholar
Schowalter, T.D., and Sexton, J.M. 1990. Effect of Leptoglossus occidentalis (Heteroptera: Coreidae) on seed development of Douglas-fir at different times during the growing season in western Oregon. Journal of Economic Entomology, 83: 1485–1486.CrossRefGoogle Scholar
Steel, R.G.D., and Torrie, J.H. 1960. Principles and procedures of statistics. McGraw-Hill, Toronto, Ontario.Google Scholar
Strong, W.B., Bates, S.L., and Stoehr, M.U. 2001. Feeding by Leptoglossus occidentalis (Hemiptera: Coreidae) reduces seed set in lodgepole pine (Pinaceae). The Canadian Entomologist, 133: 857–865.CrossRefGoogle Scholar