Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-25T06:30:09.248Z Has data issue: false hasContentIssue false
  • English
  • Français

ENTOMOPHAGA GRYLLI (FRESENIUS) INFECTIONS IN GRASSHOPPER (ORTHOPTERA: ACRIDIDAE) POPULATIONS IN SASKATCHEWAN AND ALBERTA, 1985–19861

Published online by Cambridge University Press:  31 May 2012

M. A. Erlandson ,
D. L. Johnson  and
O. O. Olfert
M. A. Erlandson
Affiliation:
Agriculture Canada Research Station, 107 Science Crescent, Saskatoon, Saskatchewan, Canada S7N OX2
D. L. Johnson
Affiliation:
Agriculture Canada Research Station, Lethbridge, Alberta, Canada T1J 4B1
O. O. Olfert
Affiliation:
Agriculture Canada Research Station, 107 Science Crescent, Saskatoon, Saskatchewan, Canada S7N OX2
Get access Rights & Permissions [Opens in a new window]

Abstract

A survey of grasshopper populations in Saskatchewan and Alberta indicated that the fungal disease caused by Entomophaga grylli (Fresenius) pathotype II was present in melanopline grasshoppers in 1985 and 1986. The disease was more prevalent and widespread in 1986, being found at 44% of 128 survey sites in Saskatchewan compared with 11% of 190 sites in 1985. In Alberta a high incidence (≥ three per 100 m2) of infected grasshoppers was found at 6% of 1746 sites in 1986 as compared with less that 1% of 2055 sites in 1985. Levels of infection based on cadaver densities at sites with high incidence of disease in Saskatchewan were similar in both years ranging from 3 to 28% for the total population. Melanoplus bivittatus (Say) was the predominant host species for E. grylli pathotype II; M. sanguinipes (Fabricius) was less affected. Entomophaga grylli pathotype I was isolated from Camnula pellucida (Scudder) hosts from a few sites in both Saskatchewan and Alberta in 1986.

Résumé

Une enquête sur les populations de criquets effectuée en Saskatchewan et en Alberta a révélé que la maladie cryptogamique causée par le pathotype II de Entomophaga grylli (Fresenius) existait chez les criquets mélanoplines en 1985 et 1986. La maladie était plus dominante et répandue en 1986, du fait qu’on l’a rencontrée dans 44% des 128 emplacements d’enquête en Saskatchewan, comparativement à 11% des 190 emplacements recensés en 1985. En Alberta, on a observé une fréquence élevée (≥ 3/100 m2) des criquets infectés dans 6% des 1746 emplacements en 1986, comparativement à moins de 1% des 2055 emplacements recensés en 1985. Les taux d’infection fondés sur les densités de cadavres rencontrées aux emplacements affichant une fréquence élevée de morbidité en Saskatchewan étaient comparables pour les 2 années, variant de 3 à 28 % pour la population totale. Melanoplus bivittatus (Say) était l’hôte dominant du pathotype II de E. grylli, alors que M. sanguinipes (Fabricius) était moins touché. Les auteurs ont isolé le pathotype I de Entomophaga grylli de l’hôte Camnula pellucida (Scudder) à quelques emplacements situés en Saskatchewan et en Alberta en 1986.

Type
Articles
Information
The Canadian Entomologist , Volume 120 , Issue 3 , March 1988 , pp. 205 - 209
Copyright
Copyright © Entomological Society of Canada 1988

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

Anonymous. 1985. Prairie Provinces Weekly Weather Summary. Environment Canada, 1985. pp. 17–36.Google Scholar
Anonymous. 1986. Prairie Provinces Weekly Weather Summary. Environment Canada, 1986. pp. 17–36.Google Scholar
Humber, R.A., Ramoska, W.A.. 1986. Variations in entomophthoralean life cycles: practical implications, pp. 190–193 in Samson, R.A., Vlak, J.M., and Peters, D. (Eds.), Fundamental and Applied Aspects of Invertebrate Pathology. Fourth International Colloquium of Invertebrate Pathology, Wageningen, Netherlands. 711 pp.Google Scholar
McDaniel, B., Bohls, R.A.. 1984. The distribution and host range of Entomophaga grylli (Fresenius), a fungal parasite of grasshoppers in South Dakota. Proc. ent. Soc. Wash. 86: 864–868.Google Scholar
Pickford, R., Riegert, P.W.. 1964. The fungous disease caused by Entomophthora grylli Fres., and its effect on grasshopper populations in Saskatchewan in 1963. Can. Ent. 96: 1158–1166.CrossRefGoogle Scholar
Shotwell, R.C. 1935. Method for making a grasshopper survey. J. econ. Ent. 28: 486–491.CrossRefGoogle Scholar
Soper, R.S., May, B., Martinell, B.. 1983. Entomophaga grylli enzyme polymorphism as a technique for pathotype identification. Environ. Ent. 12: 720–723.Google Scholar