Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-12-01T00:08:27.607Z Has data issue: false hasContentIssue false
  • English
  • Français

SUSCEPTIBILITY OF THE MIGRATORY GRASSHOPPER, MELANOPLUS SANGUINIPES (FAB.) (ORTHOPTERA: ACRIDIDAE), TO BEAUVERIA BASSIANA (BALS.) VUILLEMIN (HYPHOMYCETE): INFLUENCE OF RELATIVE HUMIDITY

Published online by Cambridge University Press:  31 May 2012

S. Marcandier  and
G.G. Khachatourians
S. Marcandier
Affiliation:
Bioinsecticide Research Laboratory, Department of Applied Microbiology and Food Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 0W0
G.G. Khachatourians*
Affiliation:
Bioinsecticide Research Laboratory, Department of Applied Microbiology and Food Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 0W0
*
2 Author to whom correspondence should be addressed.
Get access Rights & Permissions [Opens in a new window]

Abstract

In laboratory tests, Melanoplus sanguinipes (Fab.) was susceptible to infection by Beauveria bassiana (Bals.) Vuillemin conidia. Infection occurred independently of the relative humidity (RH) (12, 33, 76, 100% RH). No significant difference was observed in the final percentage mortality of the treated grasshoppers and in the lethal times (LT50)(P > 0.05) under the RH conditions studied. However, the daily rate of mortality after treatment was higher at 76% RH than at 33% RH. High natural mortality occurred at 100% RH.

At 100% RH, treatment with B. bassiana was associated with an outgrowth of microorganism that created septicemic conditions in the absence of the characteristic symptoms of mycosis. Below 100% RH, mycelial growth on cadavers was never observed, even though partial or total insect mummification occurred, and a pink body coloration on approximately 80% of the insects indicated Beauveria as the killing agent. Once transferred to 100% RH, no more than 5% of the treated grasshoppers exhibited external mycelial growth.

The microenvironment at the cuticular level of the grasshopper allows expression of conidial pathogenicity regardless of ambient RH. Hence, together, these observations suggest the feasibility of field testing with B. bassiana as a bioinsecticide against M. sanguinipes in semi-arid climatic areas.

Résumé

Melanoplus sanguinipes (Fab.) est sensible aux conidies du champignon Beauveria bassiana (Bals.) Vuillemin dans les conditions testées au laboratoire. Le processus infectieux se développe quel que soit le taux d’humidité relative (HR) (12, 33, 76 et 100%). Le pourcentage final de mortalité des insectes traités avec Beauveria est comparable dans tous les cas. Les temps léthaux (TL50) ne sont pas significativement différents (P > 0.05). Cependant le taux journalier de mortalité est supérieur à 76% HR par rapport à 33% HR. Un fort pourcentage de mortalité naturelle est observé lorsque le degré hygrométrique atteint le point de saturation.

À 100% HR, le traitement avec B. bassiana est associé au développement de microorganismes ce qui se traduit par un taux élevé de septicémies et l’absence des symptômes caractéristiques des mycoses à muscardine. Dans des conditions d’humidité relative non saturantes, la présence de mycelium sur les cadavres mommifies n’a jamais été observée, bien que la mommification totale ou partielle et la coloration rose, d’environ 80% des insectes, indique que Beauveria était l’agent pathogène responsable de leur décès. Une fois replacés à 100% HR pas plus de 5% des insectes n’ont présenté de croissance mycelienne externe.

Le microenvironnement au niveau cuticulaire est favorable à l’expression du pouvoir pathogène des spores quelle que soit l’humidité relative environnante. Cette observation permet donc d’envisager de tester B. bassiana en tant que bioinsecticide contre M. sanguinipes, en plein champ, en zones climatiques semi-arides.

Type
Articles
Information
The Canadian Entomologist , Volume 119 , Issue 10 , October 1987 , pp. 901 - 907
Copyright
Copyright © Entomological Society of Canada 1987

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

Abbott, W.S. 1925. A method of computing the effectiveness of an insecticide. J. econ. Ent. 18: 265–267.Google Scholar
Albrecht, F.O. 1962. Some physiological and ecological aspects of locust phases. Trans. R. ent. Soc. Lond. 114: 335–375.Google Scholar
Albrecht, F.O., and Blackith, R.E.. 1960. Poids et délai de survie des larves nouveau-nées chez les acridiens migrateurs. Données physiologiques. C.R. Acad. Sci. Paris 250: 3388–3390.Google Scholar
Allen, G.E., Greene, G.L., and Whitcomb, W.H.. 1971. An epizootic of Sjpicaria rileyi on the velvetbean caterpillar, Anticarsia gemmatalis, in Florida. Fla. Ent. 54: 189–191.Google Scholar
Allen, G.E., and Kish, L.P.. 1976. Monitoring of microenvironmental parameters affecting the development of epizootics of Nomuraea rileyi on the velvetbean caterpillar in soybean. Proc. 1st Int. Coll. Invertebr. Pathol, Kingston. pp. 432–433.Google Scholar
Balfour-Browne, F.L. 1960. The green muscardine disease of insects, with special reference to an epidemic in a swarm of locusts in Eritrea. Proc. R. ent. Soc. Lond. (A) 35: 65–74.Google Scholar
Clerk, G.G., and Madelin, M.F.. 1965. The longevity of conidia of three insect-parasitizing hyphomycetes. Trans. Br. mycol. Soc. 48: 193–209.Google Scholar
Doberski, J.W. 1979. Comparative laboratory studies on three fungal pathogens of the elm bark beetle Scolytus scolytus — Effect of temperature and humidity on infection of Beauveria bassiana, Metarhizium anisopliae, and Paecilomices farinosus. J. Invertebr. Pathol. 37: 195–200.Google Scholar
Ferron, P. 1977. Influence of relative humidity on the development of fungal infection caused by Beauveria bassiana (Fungi Imperfecti, Moniliales) in imagines of Acanthoscelides obtectus (Col.: Bruchidae). Entomophaga 22: 393–396.Google Scholar
Ferron, P. 1981. Pest control by the fungi Beauveria and Metarhizium. pp. 465–482in Burges, H.D. (Ed.), Microbial Control of Pests and Plant Diseases 1970–1980. Academic Press, New York.Google Scholar
Finney, D.J. 1971. Probit analysis. Cambridge University Press, Cambridge, London, New York, Melbourne. 333 pp.Google Scholar
Gage, S.H., and Mukerji, M.K.. 1978. Crop losses associated with grasshoppers in relation to economics of crop production. J. econ. Ent. 71: 487–498.Google Scholar
Harris, J.L. 1984. Grasshopper control. Saskatchewan Agriculture, Regina, Saskatchewan. 18 pp.Google Scholar
Kramer, J.P. 1980. The house fly mycosis caused by Entomophthora muscae: influence of relative humidity on infectivity and conidial germination. J. N.Y. ent. Soc. 88: 236–240.Google Scholar
Ludwig, D. 1937. The effect of different relative humidities on respiratory metabolism and survival of the grasshopper, Chortophaga viridifasciata DeGeer. Physiol. Zool. 10: 342–351.Google Scholar
MacLeod, D.M. 1954. Investigations on the genera Beauveria Vuill. and Tritirachium Limber. Can. J. Bot. 32: 818–890.Google Scholar
Marcandier, S., and Khachatourians, G.G.. 1987. Evolution of relative humidity and temperature within a closed chamber used for entomological studies. Can. Ent. 119: 893–900.Google Scholar
Parker, J.R. 1930. Some effects of temperature and moisture upon Melanoplus mexicanus mexicanus Saussure and Camnula pellucida Scudder (Orthoptera). Univ. Montana Agric. Exp. Stn. Bull. 223. 132 pp.Google Scholar
Pickford, R., and Randell, R.L.. 1969. A non-diapause strain of the migratory grasshopper, Melanoplus sanguinipes (Orthoptera: Acrididae). Can. Ent. 101: 894–896.Google Scholar
Pickford, R., and Riegert, P.W.. 1964. The fungus disease caused by Entomophthora grylli Fres., and its effects on grasshopper populations in Saskatchewan in 1963. Can. Ent. 96: 1158–1166.Google Scholar
Ramoska, W.A. 1984. The influence of relative humidity on Beauveria bassiana infectivity and replication in the chinch bug, Blissus leucopterus. J. Invertebr. Pathol. 43: 389–394.Google Scholar
Riba, G., and Entcheva, L.. 1984. Influence de l'hygrométrie ambiante sur l'agressivité comparée de plusieurs hyphomycètes entomopathogènes à l'égard de l'aleurode des serres Trialeurodes vaporariorum (Westw.). C.R. hebd. Seanc. Acad. Agri. Fr. 70(4): 521–526.Google Scholar
Riba, G., and Marcandier, S.. 1984. Influence de l'humidité relative sur l'agressivite et la viabilité des souches de Beauveria bassiana (Bals.) Vuillemin et de Metarhizium anisopliae (Metsch.) Sorokin, hyphomycètes pathogenes de la pyrale du maïs, Ostrinia nubilalis Hubn. Agronomie 4: 189–194.Google Scholar
Schaefer, E.E. 1936. The white fungus disease (Beauveria bassiana) among red locusts in S. Africa and some observations on the grey fungus disease (Empusa grylli). Union S. Afr. Dep. Agric. Sci. Bull. 160, P1. Industry Ser. 18: 5–28.Google Scholar
Schaerffenberg, B. 1966. Konnen Pilzepidemien bei Insekten kunstlich hervorgerufen werden? Z. agnew. Ent. 58: 362–372.Google Scholar
Steinhaus, E.A. 1949. Principles of insect pathology. McGraw-Hill, New York, Toronto, London. 757 pp.Google Scholar
Veen, K.H. 1968. Recherches sur la maladie due a Metarhizium anisopliae chez le criquet pèlerin. Meded. Landbouwhogeschool Wageningen 68-5. 77 pp.Google Scholar