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Histopathological changes in Heliothis armigera infected with Bacillus thuringiensis as detected by electron microscopy

Published online by Cambridge University Press:  19 September 2011

H. S. Salama
Affiliation:
Laboratory of Plant Protection, National Research Centre, Dokki, Cairo, Egypt
A. Sharaby
Affiliation:
Laboratory of Plant Protection, National Research Centre, Dokki, Cairo, Egypt
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Abstract

The histopathological changes caused by Bacillus thuringiensis var. entomocidus HD-635 in the cotton bollworm, Heliothis armigera, have been investigated using electron microscopy. Death of the larvae due to infection was a gradual process involving a sequence of symptoms. Most of the histopathological changes that occurred on the fourth day after treatment with B. thuringiensis were mainly localized in the midgut, where the epithelium was greatly affected losing its integrity; the peritrophic membrane and microvilli were degenerated; and the musculosa was also affected. Other associated effects were observed in the integument, nerve ganglion, fat body cells, tracheoles and Malpighian tubules. In the integument, the exo- and endocuticles were clumped with an obvious separation from each other. An obvious degeneration of the nerve cells surrounding the second abdominal nerve ganglion as well as the neurilemma of the nerve fibres occurred. Vacuolization of the fat body cells, degeneration of their nuclei and destruction of the membraneous sheath surrounding these cells occurred. Tracheoles showed excessive cellular hypertrophy with disintegration of its mitochondria. The Malpighian tubules showed a reduction in their lumen, with nuclei degeneration and nuclear chromatin clumping. Uric acid crystals were released in the lumen of the tubules and a rupture was observed in some parts of the microvilli. A rapid phagocytosis occurred in the haemocytes. The plasmatocytes and granular haemocytes phagocytosed the bacteria. The counts of haemocytes were at a minimum and bacterial numbers at a maximum on the fourth day after feeding the larvae on B. thuringiensis-contaminated diet.

Résumé

Les changements histopathologiquea causeś par Bacillus thuringiensis var. entomocidus HD-635 sur Heliothus armigera ont ete etudies par microscope electronique. La mortalite larvaire due a l'infection, reflete un syndrome des symptomes progressivement gradues. Les changements histopathologiques observes au 4eme jour de traitement sout principallement localises dans l'intestin moyen. C'est montre par l'epithelium largement touche qui perd son integrité en plus. La membrane peritrophic ainsi que les microvillosites sont assez dégrades, Les muscles sont aussi touches, avec quelques effets sur le teguments, ganglions nerveuses, cellules du corps gras, trachés et les tubes de Malpighies.

L'effét sur tégument est caracterisé par des changements phisiques de l'exo et endocuticle qui separent chaqun de l'autre. Une degradation nette est observee dans les cellules nerveuses entourant le second ganglion nerveuse abdominale, ausi les nerfs fibreux. Sur tissu adipeux, les vacuoles dans les cellules, degradation des noyaux et destruction de l'enveloppe de tissue est egalement distincte. Les cellules tracheoles sont excessivement hypertrophiées avec une desintegration de leur mitochondries. Les tubes de Malpighian montrent une reduction de volume de leure lumiere, degradation des noyaux et en particulier la nucléole. Dans le lumiere des tubes on observe des crystaux d'acide (uric acide), de ruptures son aussi remarqués sur quelques parties de microvillosite. Les haemocytes sont nettement phagocites. Des bacteries sont aussi phagocites par des haemocytes granulaires et de plasmocytes. Après 4 jours de traitement, le nombre des haemocytes est arrivée au minimum, par contre, de nombre de bacteries augment au maximum chez les larves infectées par contamination sue milieu artificiel.

Type
Research Articles
Copyright
Copyright © ICIPE 1985

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References

REFERENCES

Anderson, R. S., Holmes, B. and Good, R. A. (1973) In vitro bactericidal capacity of Blaberus cranifer hemocytes. J. invertebr. Path. 22, 127135.CrossRefGoogle Scholar
Atwa, W. A. and Abdel Rahman, H. A. (1974) Histo-pathological effects of Bacillus thuringiensis Berlin, on larvae of Pieris rapae (L.). Z. angew. Ent. 76, 326331.CrossRefGoogle Scholar
Cheung, P. Y. K., Grula, E. A. and Burton, R. L. (1978) Haemolymph responses in Heliothis zea to inoculation with Bacillus thuringiensis or Micrococcus lysodeikticus. J. invertebr. Path. 31, 148156.CrossRefGoogle Scholar
Crossley, A. C. S. (1964) An experimental analysis of the origins and physiology of haemocytes in the blue blow-fly Calliphora erythrocephala (Meig.). J. exp. Zool. 157, 375398.CrossRefGoogle Scholar
DeRobertis, E. D., Nowinski, A. A. and Seaz, F. (1965) Cell Biology, 4th edn, p. 117. Saunders, Philadelphia, Pa.Google Scholar
Ebershold, H. R., Luethy, P. and Mueller, M. (1977) Changes in the fine structure of the gut epithelium oí Pieris brassica induced by the δ-endotoxin of Bacillus thuringiensis. Mitt. Schweiz. Ent. Gesellsch. 50, 269276.Google Scholar
Endo, Y. and Nishitsutsuji-Uwo, J. (1980) Mode of action of Bacillus thuringiensis endotoxin. Histopathological changes in the silkworm midgut. J. invertebr. Path. 36, 90103.CrossRefGoogle Scholar
Gerald, R. S. and Earle, S. R. (1967) Histopathology of European corn borer larvae treated with Bacillus thuringiensis. J. invertebr. Path. 9, 90103.Google Scholar
Harpaz, I., Kislev, N. and Zelcer, A. (1969) Electron-microscopic studies on haemocytes of the Egyptian cotton worm, Spodoptera littoralis (Boisduval) infected with a nuclear-polyhedrosis virus, as compared to non infected haemocytes. J. invertebr. Path. 34, 207212.Google Scholar
Heimpel, A. M. and Angus, T. A. (1959) The site of action of crystalliferous bacteria in lepidoptera larvae. J. Insect Path. 1, 152170.Google Scholar
Hoopingarner, R. and Matern, M. (1964) The toxicology and histopathology of Bacillus thuringiensis Berliner in Galleria mellonella (Linn.). J. Insect Path. 6, 2630.Google Scholar
Kinsinger, R. A. and McGaughy, W. M. (1979) Histopathological effects of Bacillus thuringiensis on the larvae of the Indian meal moth and the almond moth. Ann. ent. Soc. Am. 72, 787790.CrossRefGoogle Scholar
McLaughlin, R. E. and Sikorowski, P. P. (1978) Observations of boll weevil midgut when fed natural food or on bacterially contaminated artificial diet. J. invertebr. Path. 32, 6470.CrossRefGoogle Scholar
Narayanan, K. and Jayaraj, S. (1974) Mode of action of Bacillus thuringiensis Berliner in citrus leaf caterpillar Papilio demoleus. Indian J. exp. Biol. 12, 8991.Google Scholar
Ramakrishnan, N. and Tiwari, L. D. (1967) Histopathological changes in Plusia oricholsia caused by Bacillus thuringiensis. J. invertebr. Path. 9, 579580.CrossRefGoogle Scholar
Ratcliffe, N. A. and Rowley, A. F. (1975) Cellular defence reactions of insect haemocytes in vitro. Phagocytosis in a new suspension culture system. J. invertebr. Path. 26, 225233.CrossRefGoogle Scholar
Ratcliffe, N. A. and Walters, J. B. (1983) Studies on the in vivo cellular reactions of insects: Clearance of pathogenic and non-pathogenic bacteria in Galleria mellonella larvae. J. Insect Physiol. 29, 407415.CrossRefGoogle Scholar
Reese, J. C., Yonke, T. R. and Fairchild, M. L. (1972) Fine structure of the midgut epithelium in larvae of Agrotis ipsilon. J. Kans. ent. Soc. 45, 242251.Google Scholar
Rowley, A. F. and Ratcliffe, N. A. (1976) An ultrastructural study of the in vitro phagocytosis of Escher ichia coli by the haemocytes of Calliphora erythrocephala. J. Ultrastruct. Res. 55, 193202.CrossRefGoogle Scholar
Rowley, A. F. and Ratcliffe, N. A. (1978) An ultrastructural study of the in vitro phagocytosis of Escherichia coli by the hemocytes of Calliphora erythrocephala. J. Ultrastruct. Res. 55, 193202.CrossRefGoogle Scholar
Salama, H. S. (1970) Rearing the corn borer Ostrinia nubilalis Hubn. on a semiartificial diet. Z. angew. Ent. 65, 216218.CrossRefGoogle Scholar
Salama, H. S. and Zaki, F. N. (1983) Histopathological studies on Spodoptera littoralis as affected by Bacillus thuringiensis Berliner. Ann. agric. Sci., Cairo 28, 301318.Google Scholar
Salama, H. S., Foda, M. S. and Sharaby, A. M. (1981) Potency of spore–δ-endotoxin complexes of Bacillus thuringiensis against some cotton pests. Z. angew. Ent. 91, 388398.CrossRefGoogle Scholar
Steinhaus, E. A. (1949) Principles of Insect Pathology, pp. 3740. McGraw-Hill, New York.Google Scholar
Sutter, G. R. and Raun, E. S. (1967) Histopathology of European corn borer larvae, treated with Bacillus thuringiensis. J. invertebr. Path. 9, 90103.CrossRefGoogle Scholar
Wittig, G. (1965) Phagocytosis by blood cells in healthy and diseased caterpillars 1. Phagocytosis of Bacillus thuringiensis Berliner in Pseudaletia unipuncta (Haworth). J. invertebr. Path. 7, 474488.CrossRefGoogle Scholar