Advertisement

Density and Parasitization of Grasshopper Egg-Pods in Pakistan

  • Tahira Z. Mahmood
  • M. H. Qazi
Research Article

Abstract

A total of 1244 egg-pods of 12 grasshopper species were collected — 26.7% were from low altitude hills, 23% from Swat valley, 22.1% from Punjab plains, 19.4% from Peshawar region and 8.8% from Potohar plateau. Aiolopus thalassinus was the dominant species comprising 27.7% of the total pods. This was followed by Shirakiacris shirakli (24.5%), Oxya multidentata (13.6%), Trilophidia annulata (9.7%), Spathosternum prasiniferum (9.7%), Atractomorpha acutipennis(7.4%), Stenohippus sp. (3.8%) and Phlaeoba punteli (1.8%). Others were rare being less than 1%.

Egg-pod density was effected by several closely related factors. Mean annual temperatures (15.6–23.4°C) and average precipitation (310–2100 mm) of the localities were not the ultimate controlling factors. Parasitism however, appears to play an important role. Highest parasitism of Scelio spp. was 10% on the Potohar plateau where egg-pod population was lowest. A. thalassinus was the most preferred host(41.7%) followed by S. prasiniferum (35.4%), S. shirakii (14.6%), O. multidentata (8.3%), T. annulata and Stenohippus sp. (2.1% each). Soil-type (clay-loam, loam, sandy-loam) and type of vegetationl(cultivated area, grasslands) also have a considerable bearing on the microclimate in which the insects live.

Key Words

Grasshopper egg-pod population parasitism Scelio spp 

Résumé

Un total de 1244 gousses, avec les pourcentages suivants: 26.7% des collines, 23% de la valley de Swat, 22.1% des plaines du Punjab, 195 de la region du Peshawar et 8.8% du plateau du Potohar, contenant des oeufs de 12 espèces de sauterelles a été collecté. L’ espèce dominante avec 27.7% du total des gousses fut Aiolopus thalassinus, suivit du Shirakiacris shirakii (24.5%), Oxya multidentata (13.6%), Trilophidia annulata (9.7%), Spathosternum prasiniferum (9.7%), Atractomorpha acutipennis (7.4%), Stenohippus sp. (3.8%) et Phlaeoba panteli (1.8%). Les autres espèces très rares n’ont pas fait 1%. La densité des gousses contenant des oeufs fut affecté par des différents facteurs. La moyenne annuelle des temperatures (15.6–23.4° C) et de pluviometrie (310–2100 mm) de ces localités n’étaient pas de facteurs de contrôle efficaces. Par ailleurs le parasitisme semble jouer un role important. Un parasitisme de 10% fut enregistre sur le plateau du Potohar la ou le nombre de gousses contenants des oeufs étaient très bas.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Brown V.K. (1983) Grasshoppers. Naturalists’ Handbooks 2. Cambridge University Press. Cambridge, London.Google Scholar
  2. Clark E.J. (1948) Studies in the ecology of British grasshoppers. Trans. R. ent. Soc. Lond. 99, 173–222.CrossRefGoogle Scholar
  3. Dempster J.P. (1963) The population dynamics of grasshoppers and locusts. Bio. Rev. 38, 490–529.CrossRefGoogle Scholar
  4. Ghauri A.S.K. (1960) Insect pests of Pakistan. FAO Techn. Doc. 8, 1–31.Google Scholar
  5. Greathead DJ. (1966) A brief survey of the effects of biotic factors on population of the desert locust. J. Appl. Ecol. 3, 239–250.CrossRefGoogle Scholar
  6. Irshad M., Ahmad M., Ghani M.A. and Ali R. (1978) Parasites of grasshopper (Acridoidea: Orthoptera) eggs: Distribution and life history of Scelio spp. (Hymenoptera: Scelionidae) in Pakistan. Can. Ent. 110, 449–454.CrossRefGoogle Scholar
  7. Metcalf CJL. and Flint W.P. (1951) Destructiv. and Useful Insects. McGraw-Hill Book Co. Inc. New York & London.Google Scholar
  8. Pickford R. (1972) The effects of climatic factors on egg survival and fecundity in grasshoppers. In Proceedings of the International Study Conference on the Current and Future Problems of Acridology (Edited by Hemmings CF., and Taylor T.H.C.), pp. 257–260. London: Centre for Overseas Pest Research.Google Scholar
  9. Putnam L.G. (1953) Observations on internal parasites (Hymenoptera: Scelionidae) of eggs of pest grasshopper species in the Prairie Province of Canada. Can. Ent. 85, 255–260.CrossRefGoogle Scholar
  10. Vestal D.G. (1913) Local distribution of grasshoppers in relation to plant associations. Bio. Bull. Mar. Bio. Lab. Woods Hole. 25, 141–180.CrossRefGoogle Scholar
  11. Waloff N. (1950) The egg-pods of British short-horned grasshoppers (Acrididae). Proceedings of the Royal Entomological Society of London, Series A. 25, 115–126.CrossRefGoogle Scholar
  12. Walter H. and Lieth H. (1960) Klimadiagram-Weltatlas. Klimadiagramme von Indien: 1–6. Veb. Gustav Fischer Verlag Jena.Google Scholar

Copyright information

© ICIPE 1989

Authors and Affiliations

  • Tahira Z. Mahmood
    • 1
  • M. H. Qazi
    • 2
  1. 1.National Agricultural Research CentrePakistan Agricultural Research Council P.O. National Institute of Health, ChakshahzadIslamabadPakistan
  2. 2.Quaid-e-Azam UniversityIslamabadPakistan

Personalised recommendations