Brown locust

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Roy Bateman (talk | contribs) at 14:58, 17 July 2009 (→‎Biology). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Brown locust
Brown locust(LPA) nymphs, killed by Serratia: Karoo, South Africa
Scientific classification
Kingdom:
Phylum:
Class:
Order:
Suborder:
Family:
Subfamily:
Genus:
Locustana
Species:
L. pardalina
Binomial name
Locustana pardalina
Walker, 1870

Locustana pardalina is a medium-sized small locust species found in Southern Africa and shows classic gregarious behaviour with phase polymorphism) on crowding[1].

Description

Adults

Hoppers

Distribution

Biology

"With its drought-resistant egg stage, short life cycle with 2–4 generations per year, high fecundity and highly gregarious behaviour, the Brown Locust regularly produces intense outbreaks. Eggs are usually laid in dry soil and during the summer months will hatch approximately 10 days after 15–25mm of rain has fallen. Under drought conditions, eggs enter various states of diapause and quiescence and can remain viable for up to 3 years.

Incipient outbreaks generally arise following the end of droughts and are characterised bythe dramatic increase in the density of the solitary phase adult population over wide areas of the Karoo. Hatching hoppers then aggregate and develop into thousands of small, discrete, highly gregarious hopper bands. For example, over 250,000 hopper bands and 40,000 fledging adult swarms were controlled in the massive 1985–86 upsurge. Swarming populations can then perpetuate themselves for a number of years, requiring an intense control effort, before gradually dying out during another drought cycle." [2]

Outbreaks and Control

Hopper band outbreaks are frequent in the Karoo and are controlled by farmers with insecticide spray operations: usually deltamethrin with motorised mistblowers set for ULV rates of application (subsidised by the Government).

Because of the environmental sensitivity of the Karoo biome and concerns about toxicity to grazing sheep, a biological pesticide product called 'Green Muscle', based on the entomopathogenic fungus (Metarhizium anisopliae var. acridum), was tested by the LUBILOSA Programme in collaboration with the South African Plant Protection Institute: using novel application technique to compensate for the slow speed of kill[3].

References

  1. ^ Uvarov, B.P. (1966). "Phase polymorphism". Grasshoppers and Locusts (Vol. 1). Cambridge University Press.
  2. ^ R. E. Price and H. D. Brown (2000) A Century of Locust Control in South Africa. Ch 4. Workshop on Research Priorities for Migrant Pests of Agriculture in Southern Africa,Plant Protection Research Institute, Pretoria, South Africa, 24–26 March 1999.R. A. Cheke, L. J. Rosenberg and M. E. Kieser (eds) (2000) Natural Resources Institute,Chatham, UK.
  3. ^ Price, R.E., Bateman, R.P., Brown, H.D., Butler, E.T. and Müller, E.J. (1997) Aerial spray trials against brown locust (Locustana pardalina, Walker) nymphs in South Africa using oil-based formulations of Metarhizium flavoviride. Crop Protection, 16, 345-351

Notes

This is a stub