Hostname: page-component-7479d7b7d-q6k6v Total loading time: 0 Render date: 2024-07-08T13:38:16.434Z Has data issue: false hasContentIssue false
  • English
  • Français

Adjuvants to improve aerial control of the citrus mealybug Planococcus citri (Hemiptera: Pseudococcidae) using entomopathogenic nematodes

Published online by Cambridge University Press:  11 November 2013

S. van Niekerk  and
A.P. Malan
S. van Niekerk
Affiliation:
Department of Conservation Ecology and Entomology, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Matieland7602, South Africa
A.P. Malan*
Affiliation:
Department of Conservation Ecology and Entomology, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Matieland7602, South Africa
*
*E-mail: apm@sun.ac.za
Get access Rights & Permissions [Opens in a new window]

Abstract

The citrus mealybug, Planococcus citri, is a highly destructive pest of citrus, occurring only in the aerial parts of plants. Humidity will be one of the key factors to consider when using entomopathogenic nematodes (EPN) as biological control agents. Different adjuvants can be added to suspensions of EPNs, to improve control as a foliar application. An aqueous suspension containing Heterorhabditis zealandica and 0.3% Zeba® significantly increased P.citri mortality by 22% at 80% relative humidity (RH) with a temperature cycle starting at 22°C for 14 h and 11°C for 11 h. The same polymer formulation was tested for Steinernema yirgalemense and mortality of P. citri increased by 21% at 60% RH and by 27% at 80% RH. The addition of Nu-Film-P® and Zeba® to H. zealandica suspensions did not significantly retard application run-off on citrus leaves. The combination of Nu-Film-P® and Zeba®, however, was able to significantly retard sedimentation, increasing the average number of nematodes deposited on 2-cm2 leaf discs by 10 nematodes. In an aqueous suspension, nematodes settle rapidly to the bottom, resulting in an uneven distribution of nematodes. Xanthan gum, at a concentration of 0.2%, was highly effective at retarding sedimentation, with 72% of the initial nematode number still in suspension after 1 h. Zeba®, at a concentration of 0.3%, despite not being as effective as Xanthan gum, nevertheless still retarded sedimentation significantly. This is the first report of the potential of Nu-Film-P® and Zeba® to improve EPN performance against P. citri when used above ground in citrus orchards.

Type
Research Papers
Information
Journal of Helminthology , Volume 89 , Issue 2 , March 2015 , pp. 189 - 195
Copyright
Copyright © Cambridge University Press 2013 

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. Journal of Economic Entomolology 18, 265–267.Google Scholar
Bartlett, B.R. & Lloyed, D.C. (1958) Mealybugs attacking citrus in California – a survey of their natural enemies and the release of new parasites and predators. Journal of Economic Entomolology 52, 90–93.Google Scholar
Blumberg, D. & Van Driesche, R.G. (2001) Encapsulation rates of three encyrtid parasitoids by three mealybug species (Homoptera: Pseudococcidae) found commonly as pests in commercial greenhouses. Biological Control 22, 191–199.Google Scholar
Blumberg, D., Klein, M. & Mendel, Z. (1995) Response by encapsulation of four mealybug species (Homoptera, Pseudococcidae) to parasitisation by Anagyrus pseudococci. Phytoparasitica 23, 157–163.Google Scholar
De Waal, J.Y., Malan, A.P. & Addison, M.F. (2013) A superabsorbent polymer formulation for improved efficacy of Heterorhabditis zealandica (Rhabditida: Heterorhabditidae) control of codling moth larvae, Cydia pomonella (L.) (Lepidoptera: Tortricidae). Biocontrol Science and Technology 23, 62–78.Google Scholar
Efron, B. & Tibshirani, R. (1993) An introduction to the bootstrap. 436 pp. Boca Raton, CRC.Google Scholar
Franco, J., Suma, P., Da Silva, E., Blumberg, D. & Mendel, Z. (2004) Management strategies of mealybug pests of citrus in mediterranean countries. Phytoparasitica 32, 507–522.CrossRefGoogle Scholar
Gaugler, R. & Boush, G.M. (1978) Effects of ultraviolet radiation and sunlight on the entomopathogenic nematode, Neoaplectana carpocapsae. Journal of Invertebrate Patholology 32, 291–296.Google Scholar
Gaugler, R. & Boush, G.M. (1979) Nonsusceptibility of rats to the entomogenous nematode Neoaplectana carpocapsae. Environmental Entomolology 8, 656–660.Google Scholar
Gaugler, R., Bednarek, A. & Campbell, J.F. (1992) Ultraviolet inactivation of heterorhabditid and steinernematid nematodes. Journal of Invertebrate Pathology 59, 155–160.CrossRefGoogle Scholar
Grewal, P., Ehlers, R.-U. & Shapiro-Ilan, D.I. (2005) Nematodes as biological control agents. Wallingford, UK, CAB International.Google Scholar
Gullan, P.J. (2000) Identification of the immature instars of mealybugs (Hemiptera: Pseudococcidae) found on citrus in Australia. Australian Journal of Entomolology 39, 160–166.Google Scholar
Hattingh, V. (1993) Mealybugs and cottony cushion scale on citrus in Southern Africa. Citrus Journal 3, 20–22.Google Scholar
Hattingh, V. & Moore, S.D. (2003) Mealybugs. pp. 65–69in Grout, T.G. (Ed.) Integrated production guidelines for export citrus. Integrated Pest and Disease Management. Nelspruit, CRI.Google Scholar
Hattingh, V. & Tate, B.A. (1995) Effects of field-weathered residues of insect growth regulators on some Coccinellidae (Coleoptera) of economic importance as biological control agents. Bulletin of Entomological Research 85, 489–493.Google Scholar
Hattingh, V. & Tate, B.A. (1996) The pest status of mealybugs on citrus in Southern Africa. Proceedings of the International Society of Citriculture 1, 560–563.Google Scholar
Hattingh, V., Cilliers, C.J. & Bedford, E.C.G. (1998) Citrus mealybugs. pp. 112–120in Bedford, E.C.G., Van den Berg, M.A. & De Villiers, E.A. (Eds) Citrus pests in the Republic of South Africa. Nelspruit, ARC-Institute for Tropical and Subtropical Crops.Google Scholar
Kaya, H.K. & Stock, S.P. (1997) Techniques in insect nematology. pp. 281–301in Lacey, L.A. (Ed.) Manual of techniques in insect pathology. London, Academic Press.Google Scholar
Lacey, L.A., Neven, L.G., Headrick, H. & Fritts, R.J. (2005) Factors affecting entomopathogenic nematodes (Steinernematidae) for control of overwintering codling moth (Lepidoptera: Tortricidae) in fruit bins. Journal of Economic Entomology 6, 1863–1869.CrossRefGoogle Scholar
Mahfoudhi, N.D. & Dhouibi, M.H. (2009) Survey of mealybugs (Hemiptera: Pseudococcidae) and their natural enemies in Tunisian vineyards. African Entomolology 17, 154–160.Google Scholar
Malan, A.P., Nguyen, K.B. & Addison, M.F. (2006) Entomopathogenic nematodes (Heterorhabditidae and Steinernematidae) from the southwestern parts of South Africa. African Plant Protection 12, 65–69.Google Scholar
Malan, A.P., Knoetze, A.P. & Moore, S.D. (2011) Isolation and identification of entomopathogenic nematodes from citrus orchards and their biocontrol potential against false codling moth. Journal of Invertebrate Pathology 108, 115–125.CrossRefGoogle ScholarPubMed
Michelakis, S. & Hamid, H.A. (1995) Integrated control methods of the citrus mealybug, Planococcus citri (Risso) in Crete, Greece. Israel Journal of Entomolology 29, 277–284.Google Scholar
Mráček, Z. (2002) Use of entomoparasitic nematodes (EPANS) in biological control. pp. 235–264in Upadhyay, R.K. (Ed.) Advances in microbial control of insects. New York, Kluwer Academic, Plenum Publishers.CrossRefGoogle Scholar
Navon, A. & Ascher, K.R.S. (2000) Bioassays of entomopathogenic microbes and nematodes. Wallingford, UK, CABI.Google Scholar
Nguyen, K.B. (2007) Methodology, morphology and identification. pp. 59–119in Nguyen, K.B. & Hunt, D.J. (Eds) Nematology monographs and perspectives, Vol. 5, Entomopathogenic nematodes: Systematics, phylogeny and bacterial symbionts. Leiden, The Netherlands, Koninklijke Brill NV.CrossRefGoogle Scholar
Pieterse, W., Muller, D.L. & Jansen van Vuuren, B. (2010) A molecular identification approach for five species of mealybug (Hemiptera: Pseudococcidae) on citrus fruit exported from South Africa. African Entomolology 18, 23–28.Google Scholar
Schroer, S. & Ehlers, R.-U. (2005) Foliar application of the entomopathogenic nematode Steinernema carpocapsae for biological control of diamondback moth larvae (Plutella xylostella). Biological Control 33, 81–86.CrossRefGoogle Scholar
Schroer, S., Ziermann, D. & Ehlers, R.-U. (2005) Mode of action of a surfactant–polymer formulation to support performance of the entomopathogenic nematode Steinernema carpocapsae for control of diamondback moth larvae (Plutella xylostella). Biocontrol Science and Technolology 15, 601–613.Google Scholar
Smith, D., Beattie, G.A.C. & Broadle, R. (1997) Citrus pests and their natural enemies: Integrated Pest Management in Australia. Queensland Department of Primary Industries, Queensland, Australia.Google Scholar
Tomalak, M., Piggott, S. & Jagdale, G.B. (2005) Glasshouse applications. pp. 147–166in Grewal, P.S., Ehlers, R.-U. & Shapiro-Ilan, D.I. (Eds) Nematodes as biocontrol agents. Wallingford, UK, CAB International.Google Scholar
Unruh, T.R. & Lacey, L.A. (2001) Control of codling moth, Cydia pomonella (Lepidoptera: Tortricidae), with Steinernema carpocapsae: Effects of supplemental wetting and pupation site on infection rate. Biological Control 20, 48–56.Google Scholar
Van Niekerk, S. & Malan, A.P. (2012) Potential of South African entomopathogenic nematodes (Heterorhabditidae and Steinernematidae) for control of the citrus mealybug, Planococcus citri (Pseudococcidae). Journal of Invertebrate Pathology 111, 166–176.CrossRefGoogle ScholarPubMed
Wakgari, W.M. & Giliomee, J.H. (2003) The biology of three mealybug species (Hemiptera: Pseudococcidae) found on citrus in the Western Cape Province, South Africa. African Entomology 11, 173–182.Google Scholar
Wakgari, W.M. & Giliomee, J.H. (2005) Description of adult and immature females of six mealybug species (Hemiptera: Pseudococcidae) found on citrus in South Africa. African Entomology 13, 281–332.Google Scholar
Winston, P.W. & Bates, D.H. (1960) Saturated solutions for the control of humidity in biological research. Ecology 41, 232–237.Google Scholar
Wright, D.J., Peters, A., Schroer, S. & Fife, J.P. (2005) Application technology. pp. 91–106in Grewal, P.S., Ehlers, R.-U. & Shapiro-Ilan, D.I. (Eds) Nematodes as biocontrol agents. Wallingford, UK, CAB International.Google Scholar