​Biological control of insect and mite pests on tomatoes: Survey of the natural enemy fauna of South Africa


Although a number of natural enemies for control of horticultural pests are available from overseas companies, it is impractical to import natural enemies in large numbers into South Africa because of environmental concerns and import restrictions, and distance and costs involved.

A joint initiative by ARC-PPRI Insect Ecology Division together with the Tomato Producers' Organisation aims to utilise South Africa’s fauna of natural enemies (parasitic wasps and predacious insects, mites and spiders) for the biological control of the ten most important insect and six most important mite pests on tomatoes as listed in Table 1.

Table 1. Key insect and mite pests of tomato recorded in South Africa



1.Bemisia tabaci (Gennadius)Hemiptera, AleyrodidaeTobacco, cotton or sweetpotato whitefly
2.Trialeurodes vaporariorum (Westwood)Hemiptera, AleyrodidaeGreenhouse whitefly
3.Macrosiphum euphorbiae (Thomas)Hemiptera, AphididaePotato aphid
4.Myzus persicae (Sulzer)Hemiptera, AphididaeGreen peach aphid
5.Frankliniella occidentalis (Pergande)Thysanoptera, ThripidaeWestern flower thrip
6.Thrips tabaci LindemanThysanoptera, ThripidaeOnion thrips
7.Liriomyza trifolii (Burgess)Diptera, AgromyzidaeAmerican leafminer
8.Phthorimaea operculella (Zeller)Lepidoptera, GelechiidaePotato tuber moth
9.Chrysodeixis acuta (Walker)Lepidoptera, NoctuidaeTomato semi-looper
10.Helicoverpa armigera (Hübner)Lepidoptera, NoctuidaeAfrican cotton bollworm (often wrongly referred to as American bollworm)



1.Tetranychus urticae Koch2Acari, TetranychidaeTwo-spotted spider mite
2.Tetranychus cinnabarinus (Boisduval)2Acari, TetranychidaeCommon red spider mite
3.Tetranychus evansi Baker & PritchardAcari, TetranychidaeTobacco spider mite
4.Tetranychus lombardinii Baker & PritchardAcari, TetranychidaeCrimson spider mite
5.Tetranychus ludeni ZacherAcari, TetranychidaeDark-red spider mite
6.Aculops lycopersici (Tryon)Acari, EriophyidaeTomato rust mite
1Although Agrotis spp. (Lepidoptera: Noctuidae; cutworms) are important pests no suitable insect natural enemies have been identified to date and other control measures have to be used.
2These two taxa belong to a complex of closely related species; some acarologists consider T. cinnabarinus to be a good species, but others recognise it as a junior synonym of T. urticae.

Survey of natural enemies

Qualitative surveys of natural enemies of key pests in three tomato-producing areas in the Northern Province, the North-West Province, and Gauteng Province, have been conducted. During the surveys, 42 sites in the three provinces were visited from November 1999 to April 2000. Based on the results of these recent surveys, scientific literature and records of specimens collected previously, potential biological control agents were selected for further evaluation against the ten most important insect and six most important mite pests on tomatoes.