Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-27T08:32:15.712Z Has data issue: false hasContentIssue false
  • English
  • Français

Interrelationship between an entomogenous fungus and two ant-homopteran (Hymenoptera: Formicidae-Hemiptera: Pseudococcidae & Aphididae) mutualisms on guava trees

Published online by Cambridge University Press:  10 July 2009

M. J. Samways
M. J. Samways
Affiliation:
Citrus & Subtropical Fruit Research Institute Nelspruit, South Africa.
Get access Rights & Permissions [Opens in a new window]

Abstract

On guava trees at Nelspruit, South Africa, there was a mutualism between the ant Anoplolepis custodiens (F. Sm.) and the mealybug Planococcus citri (Risso), which raised the population levels of both. When ants were excluded from half the trees, their overall population level also dropped by half. Further, they moved their nests to be as near as possible to their main food source, the honeydew of the mealybugs. When deprived of their ant mutualists, the mealybugs were heavily preyed on by coccinellids such as the ant–intolerant Exochomus flavipes (Thnb.) and the ant–tolerant Scymnus spp. Later, the mealybugs were almost totally eliminated by the primary entomogenous fungus Cladosporium sp. near C. oxysporum. The coccinellids, now without food, were forced to abandon the trees. In contrast, in trees where ants were allowed to continue their normal activity, the epizootic among the mealybugs was delayed by 14 days. This limitation by the ants of disease allowed a basal but fragmented mealybug population to survive. As the mealybugs declined, the ants switched to attending the aphid Aphis gossypii Glov. Fifteen days after the epizootic struck the ant–attended mealybug population, it began to devastate the aphid population. With both mealybugs and aphids at a low level, the ant population declined. However, the ant–homopteran mutualisms, although severely hit by the epizootic, nevertheless remained intact.

Type
Original Articles
Information
Bulletin of Entomological Research , Volume 73 , Issue 2 , June 1983 , pp. 321 - 331
Copyright
Copyright © Cambridge University Press 1983

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

Addicott, J. F.. (1978). Competition for mutualists: aphids and ants. — Can. J. Zool. 56, 2093–2096.CrossRefGoogle Scholar
Evans, H. C. (1982). Entomogenous fungi in tropical forest ecosystems: an appraisal. — Ecol, Entomol. 7, 47–60.Google Scholar
Le Pelley, R. H. (1968). Pests of coffee. — 590 pp. London, Longmans.Google Scholar
Paine, R. T.. (1980). Food webs: linkage, interaction strength and community infrastructure.—J. Anim. Ecol. 49, 667–685.CrossRefGoogle Scholar
Samways, M. J.. (1981). Comparison of ant community structure (Hymenoptera: Formicidae) in citrus orchards under chemical and biological control of red scale, Aonidiella aurantü (Maskell) (Hemiptera: Diaspididae).—Bull. ent. Res. 71, 663–670.CrossRefGoogle Scholar
Samways, M. J.. (1982). Ecologically sound and commercially acceptable control of ants in guava trees.—Subtropica 3, 19–20.Google Scholar
Samways, M. J.. (in press).(1982) Community structure of ants (Hymenoptera: Formicidae) in a series of habitats associated with citrus.—J. appl. Ecol.Google Scholar
Samways, M. J.., Nel, M.Prins, A. J. (1982). Ants (Hymenoptera: Formicidae) foraging in citrus trees and attending honeydew–producing Homoptera.—Phytophylactica 14, 155–157.Google Scholar
Schwartz, R. E.. (1978). Citrus aphids in Bedford, E. C. G. (Ed.). Citrus pests in the Republic of South Africa. —Pretoria, Department of Agricultural Technical Services. – pp. 81–84Google Scholar
Smit, B.. Bishop, H. J.. (1934). A study of the citrus mealybug and its association with ants in the Eastern Province.—Sci. Bull. Dep. Agric. Un. S. Afr. no. 125, 41 pp.Google Scholar
Steyn, J. J. (1954). The pugnacious ant (Anoplolepis custodiens Smith) and its relation to the control of citrus scales at Letaba.—Mem. ent. Soc. sth. Afr. no. 3, 96 pp.Google Scholar
Strickland, A. H.. (1947). Coccids attacking cacao (Theobroma cacao, L.), in West Africa, with descriptions of five new species.—Bull. ent. Res. 38, 497–523.CrossRefGoogle ScholarPubMed
Way, M. J.. (1963). Mutualism between ants and honeydew-producing Homoptera.—A. Rev. Ent. 8,307–344.CrossRefGoogle Scholar
Whitehead, V. B.. (1957). A study of the predators and parasites of Planococcus citri (Risso) (Homoptera) on vines in the western Cape Province, South Africa.—280 pp. M.Sc. thesis,Rhodes University, Grahamstown.Google Scholar