Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-24T18:01:19.373Z Has data issue: false hasContentIssue false
  • English
  • Français

The population dynamics of Cryptolestes ferrugineus (Stephens) (Col., Cucujidae) in flour and on Manitoba wheat

Published online by Cambridge University Press:  10 July 2009

K. R. Ashby
K. R. Ashby
Affiliation:
Agricultural Research Council, Pest Infestation Laboratory, London Road, Slough.
Get access Rights & Permissions [Opens in a new window]

Summary

If adults of Cryptolestes ferrugineus (Steph.), of which the females have already been fertilised, are cultured on flour at low densities, the rate of oviposition is independent of the density of adults and juvenile mortality is negligible. At high densities there is a heavy mortality amongst eggs and young larvae, and there is evidence that, providing no great degree of conditioning of the medium has occurred, an equilibrium is reached with the number of eggs plus larvae present at any time being independent of the density of adults. Cannibalism is undoubtedly a major cause of the juvenile mortality under these conditions. Where crowding of adults is so great that conditioning of the medium becomes important, the number of eggs plus larvae present at a given time after the cultures have been set up decreases with increasing density of adults, there being some indication of an inverse linear relation.

Cultures of C. ferrugineus on a mixture at 70 per cent. R.H. of sound grain and grain already slightly damaged by Crypiolestes are capable of initiating dense infestations in the laboratory, at least at moderate and high temperatures. Under optimal conditions the infestations develop within 15 days. Values deduced for the pre-adult period at various temperatures were similar to those obtained by Rilett (1949). At 17°C., development was extremely slow but the low temperature did not increase mortality. Cannibalism and competition by adults and fully developed larvae appear to play an important part in limiting the production and survival of the juvenile stages.

Sound grain at 70 per cent. R.H. is unsuitable as a medium for culturing Cryptolestes in the laboratory but it becomes suitable after relatively small additions of flour and damaged grains. At 33°C. at least, a point is suddenly reached where an infestation is initiated, the critical feature being increased survival of larvae rather than an increase in the number of eggs laid. An increase in humidity has a similar effect to adding food.

Estimates of the production of CO2 at various temperatures gave values higher than previously reported. From 21 to 33°C. the rate of increase of the respiration rate and the increase in the speed of development are proportional to rise in temperature. This is in accord with other indications that C. ferrugineus has a high optimum temperature.

Type
Research Paper
Information
Bulletin of Entomological Research , Volume 52 , Issue 2 , June 1961 , pp. 363 - 379
Copyright
Copyright © Cambridge University Press 1961

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

Andkewartha, H. G. & Birch, L. C. (1954). The distribution and abundance of animals.—782 pp. Chicago, Ill., Univ. Chicago Press.Google Scholar
Ashby, K. R. (1961). The life-history and reproductive potential of Cryptolestes pusillus (Schönherr) (Col., Cucujidae) at high temperatures and humidities.—Bull. ent. Res. 52 pp. 353–361.CrossRefGoogle Scholar
Boyce, J. M. (1946). The influence of fecundity and egg mortality on the population growth of Tribolium confusum Duval.—Ecology 27 pp. 290–302.CrossRefGoogle Scholar
Crombie, A. C. (1942). The effect of crowding upon the oviposition of grain-infesting insects.—J. exp. Biol. 19 pp. 311–340.CrossRefGoogle Scholar
Crombie, A. C. (1944). The effect of crowding upon the natality of grain-infesting insects.—Proc. zool. Soc. Lond. (A) 113 pp. 77–98.Google Scholar
Davies, R. G. (1949). The biology of Laemophloeus minutus Oliv. (Col. Cucujidae).—Bull. ent. Res. 40 pp. 63–82.CrossRefGoogle Scholar
Finlayson, L. H. (1950). The biology of Cephalonomia waterstoni Gahan (Hym., Bethylidae), a parasite of Laemophloeus (Col., Cucujidae).—Bull. ent. Res. 41 pp. 79–97.CrossRefGoogle Scholar
Holdaway, F. G. (1932). An experimental study of the growth of populations of the “ flour beetle ” Tribolium confusum Duval, as affected by atmospheric moisture.—Ecol. Monogr. 2 pp. 261–304.CrossRefGoogle Scholar
Howe, R. W. & Lefkovitch, L. P. (1957). The distribution of the storage species of Cryptolestes (Col., Cucujidae).—Bull. ent. Res. 48 pp. 795–809.CrossRefGoogle Scholar
Howe, R. W. & Oxley, T. A. (1944). The use of carbon dioxide production as a measure of infestation of grain by insects.—Bull. ent. Res. 35 pp. 11–22.CrossRefGoogle Scholar
Lefkovitch, L. P. (1957). The biology of Cryptolestes ugandae Steel & Howe (Coleoptera, Cucujidae), a pest of stored products in Africa.—Proc. zool. Soc. Lond. 128 pp. 419–429.CrossRefGoogle Scholar
Lucas, C. E. & Oxley, T. A. (1946). Study of an infestation by Laemophloeus sp. (Coleoptera, Cucujidae) in bulk wheat.—Ann. appl. Biol. 33 pp. 289–293.CrossRefGoogle Scholar
Rilett, R. O. (1949). The biology of Laemophloeus ferrugineus (Steph.).—Canad. J.Res. (D)27 pp. 112–148.CrossRefGoogle ScholarPubMed
Smallman, B. N. (1944).—Entomological investigations.—Rep. Grain Res. Lab. Canada 18 pp. 39–40.Google Scholar
Wigglesworth, V. B. (1953). The principles of insect physiology.—5th edn., 546 pp. London, Methuen.Google Scholar
Williams, G. C. (1954). Observations on the life history of Laemophloeus minutus (Ol.) (Col. Cucujidae) when bred on various stored cereals and cereal products.—Bull. ent. Res. 45 pp. 341–350.CrossRefGoogle Scholar