Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-27T07:13:12.851Z Has data issue: false hasContentIssue false
  • English
  • Français

Development of the Parasitoid Microplitis rufiventris Reared in Hosts Treated with Lefenuron, a Chitin Synthesis Inhibitor

Published online by Cambridge University Press:  19 September 2011

E. M. Hegazi ,
A. M. El-Minshawy ,
W. E. Khafagi  and
N. El-Singaby
E. M. Hegazi*
Affiliation:
Department of Entomology, Faculty of Agriculture, Alexandria University, Egypt
A. M. El-Minshawy
Affiliation:
Department of Entomology, Faculty of Agriculture, Alexandria University, Egypt
W. E. Khafagi
Affiliation:
Plant Protection Research Institute, Sabahia, Alexandria, Egypt
N. El-Singaby
Affiliation:
Department of Entomology, Faculty of Agriculture, Alexandria University, Egypt
*
Corresponding author: EMH.
Get access

Abstract

Eggs and larvae of Microplitis rufiventris Kok. (Braconidae: Hymenoptera) were exposed to two sublethal concentrations (0.2 and 0.4 ppm) of the chitin synthesis inhibitor lefenuron, by feeding treated artificial diet to their hosts, Spodoptera littoralis (Boisd.) (Noctuidae: Lepidoptera) larvae. Each concentration was initiated during the egg stage or different instars of the parasitoid larvae. Between 4.3 and 33.8% of parasitoid larvae in lefenuron-treated hosts showed morphological and developmental abnormalities. The effect of the compound on the developmental rate and sensitivity of the parasitoid larvae varied according to the parasitoids' age at treatment; the egg stage and older parasitoid larvae were more tolerant to the compound than the first instars. In all treated hosts the developmental rate of the parasitoid was lower than that of controls. The lower lefenuron concentration (0.2 ppm) was more effective at disrupting the development of young parasitoid larvae than the higher one. Delayed or latent effects of the compound were evident in non-emergence of parasitoid adults that were exposed to the compound as first instars. Reduced sensitivity of old parasitoid larvae could be compatible with survival of the parasitoid in integrated control programme of S. littoralis.

Résumé

Les oeufs et larves de Microplitis rufiventris Kok. (Hymenoptera: Braconidae) étaient exposés á deux concentrations sub-létales (0,2 et 0,4 ppm) de lefénuron, un inhibiteur de synthèse de la chitin, par alimentation sur milieu artificiel des chenilles de Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) qui sont des hôtes du braconidé. Chaque dose était administrée au stade oeuf ou á des différents stades larvaires du parasitoïde. Les chenilles nourries au lefénuron ont révélé entre 4,3 et 33,8% de larves mal développées du parasitoïde et possédant des anomalies morphologiques. L'effet du lefénuron sur le taux de croissance et de développement ainsi que sur la sensibilité des larves variaient avec l'âge du parasitoïde, au moment du traitement. Les oeufs et larves âgées du parasitoïde étaient plus tolérants vis-á-vis du produit plus que les jeunes stades. La basses concentration du lefénuron pertubait le développement des jeunes larves plus que les concentrations élevées. L'arrière-effet et la latence du produit étaient manifestes et ils étaient reflétés par la non-émergence des adultes chez les larves exposées au produit á leur premier stade de développement. Dans un programme de lutte intégrée contre S. littoralis, une sensibilité réduite des larves âgées du parasitoïde pourrait présager une survie du parasitoïde.

Keywords

Spodoptera littoralisMicroplitis rufiventrislefenuronendodevelopmental rateSpodoptera littoralisMicroplitis rufiventrislefénurontaux de développement interne
Type
Research Articles
Information
International Journal of Tropical Insect Science , Volume 19 , Issue 2-3 , September 1999 , pp. 199 - 206
Copyright
Copyright © ICIPE 1999

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

REFERENCES

Bartlett, B. R. (1958) Laboratory studies on selective aphicides favoring natural enemies of the spotted alfalfa aphid, J. Econ. Entonwl. 51, 374–378.Google Scholar
Bartlett, B. R. (1964) Integration of chemical and biological control, pp. 489–514. In Biological Control of Insect Pests and Weeds (Edited by De Bach, P.). Reinhold, New York. 844 pp.Google Scholar
Beckage, N. E., Metcalf, J. S., Nesbit, D.J., Schleifer, K. W., Zetlan, S. R. and DeBuron, I. (1990) Host haemolymph monophenoloxidase activity in parasitized Manduca sexta larvae and evidence for inhibition by wasp polydnavirus. Insect Biochem. 20, 285–294.CrossRefGoogle Scholar
Deakle, J. P. and Bradley, J. R. (1982) Effects of early season applications of diflubenzuron and azinphosmethyl on population levels of certain arthropods in cotton fields, J. Ga. Entomol. Soc. 17, 200–204.Google Scholar
El-Sawy, E. A. (1994) Effect of some insect growth regulators on the braconid parasite Microplitis rufiventris Kok. MSc Thesis, Faculty of Agriculture, University of Alexandria, Egypt.Google Scholar
Granett, J. and Weseloh, R. M. (1975) Dimilin toxicity to the Gypsy moth larval parasitoid, Apanteles melanoscelns. J. Econ. Entomol. 68, 577–580.CrossRefGoogle Scholar
Hegazi, E. M. and El-Minshawy, A. M. (1979) Laboratory technique for mass rearing of Microplitis rufiventris Kok. (Braconidae; Hymenoptera) an internal parasite of the cotton leafworm, Spodoptera littoralis (Boisd.) (Noctuidae; Lepidoptera). Boll. Lab. Ent. Agr. “F. Silvestri” 36, 205–210.Google Scholar
Hegazi, E. M., El-Menshawy, A. M. and Hammad, S. M. (1977) Mass rearing of the Egyptian cotton leafworm, Spodoptera littoralis (Boisd.) on semi-artificial diet, pp. 61–70. In Proceedings Second Arab Pesticide Conference, Tanta University. Tanta Press, Egypt.Google Scholar
Horn, D. J. (1988) Ecological Approach to Pest Management. Guilford, New York.Google Scholar
Kitano, H., Wago, H. and Arakawa, T. (1990) Possible role of teratocytes of the gregarious parasitoid, Colesia (= Apanteles) glomerata in the suppression of phenoloxidase activity in the larval host, Pieris rapae crucivora. Arch. Insect Biochem. Physioi. 13, 177–185.CrossRefGoogle Scholar
Ripper, W. E. (1944) Biological control as a supplement to chemical control of insect pests. Nature (Lond.) 153 448–452.CrossRefGoogle Scholar
Stern, V. M. (1963) The effect of various insecticides on Trichogramma semifumatum and certain predators in Southern California, J. Econ. En t omol. 56, 348–350.Google Scholar
Stoltz, D. B. and Cook, D. I. (1983) Inhibition of host phenoloxidase activity by parasitoid Hymenoptera. Experientia 39, 1022–1024.CrossRefGoogle Scholar
Strand, M. R., Vinson, S. B., Nettles, W. C. Jr., and Xie, Z. N. (1988) In vitro culture of the egg parasitoid Telenomus heliothidis: The role of teratocytes and medium consumption in development. Entomol. Exp. Appi. 46, 71–78.CrossRefGoogle Scholar
Stroka, P. and Vinson, S. B. (1978) Phenoloxidase activity in the haemolymph of parasitized and unparasitized Heliothis virescens. Insect Biochem. 8, 399–402.CrossRefGoogle Scholar
Tamashiro, M. and Sherman, M. (1955) Direct and latent toxicity of insecticides to Oriental fruit fly larvae and their internal parasites, J. Econ. Entomol. 48, 75–79.CrossRefGoogle Scholar
Tanaka, T. and Wago, H. (1990) Ultrastructural and functional maturation of teratocytes of Apanteles kariyai. Arch. Insect Biochem. Physioi. 13, 187–197.CrossRefGoogle Scholar
Wilkinson, J. D. and Ignoffo, C. M. (1973) Activity of a juvenile hormone analogue on a parasitoid, Apanteles rabeada, via its host, Pieris rapae. J. Econ. Entomol. 66, 643–646.CrossRefGoogle Scholar
Wilkinson, J. D., Biever, K. D., Ignoffo, C. M., Pons, W. J., Morrison, R. K. and Seay, R. S. (1978) Evaluation of diflubenzuron formulations on selected insect parasitoids and predators, J. Georgia Entomol. Soc. 13, 227–236.Google Scholar
Wright, J. E. and Spates, G. E. (1972) A new approach in integrated control: Insect juvenile hormone plus a hymenopteran parasite against the stable fly. Science (Wash., D.C.) 178, 1292–1294.CrossRefGoogle Scholar