Hostname: page-component-7bb8b95d7b-wpx69 Total loading time: 0 Render date: 2024-09-12T16:50:12.264Z Has data issue: false hasContentIssue false

RELATIONSHIPS BETWEEN THE PARASITOID HYPOSOTER EXIGUAE AND THE CABBAGE LOOPER, TRICHOPLUSIA NI: EFFECTS ON HEAD-CAPSULE WIDTH, LIVE AND DRY WEIGHTS, AND HEMOLYMPH SPECIFIC GRAVITY OF HOSTS AT DIFFERENT AGES12

Published online by Cambridge University Press:  31 May 2012

Gerard F. Iwantsch
Affiliation:
Pesticide Research Laboratory and Graduate Study Center, The Pennsylvania State University, University Park
Zane Smilowitz
Affiliation:
Pesticide Research Laboratory and Graduate Study Center, The Pennsylvania State University, University Park

Abstract

The effects of parasitism by Hyposoter exiguae (Viereck) on certain developmental parameters of Trichoplusia ni (Hübner) were influenced by host age at parasitism.

Head-capsule growth increments for parasitized Trichoplusia ni became smaller with each successive molt during parasitism so that determination of instar on the basis of head-capsule width became impossible.

Parisitized T. ni showed a proportionately smaller gain in weight from time of stinging until parasitoid emergence the older they were when stung (6 times for 3rd instars; 2 times for 4th instars; and no gain for 5th instars). This retardation was evident 24 h after parasitism. Essentially the same results were obtained for dry weight.

Percentage dry weight of parasitized larvae tended to increase over control values until the 5th stadium when controls abruptly increased. Values for parasitized 5ths remained below the controls. Values found on the last days reflected those of the parasitoid which composed most of the mass inside the host cuticle.

Hemolymph specific gravity in controls and parasitized 3rd instars oscillated with a frequency of one stadium in the 3rd, 4th, and early 5th stadia. Specific gravity of controls then rose to a maximum of 1.0501 in the prespinning phase and dropped by the pharate–pupal phase. Values for parasitized larvae in the 5th stadium rose slightly before leveling off, and parasitized 5th instars rose to a maximum on the next-to-last day. Maximum values attained for hosts parasitized as 3rd and 5th instars never reached that for controls on day 11. This may be related to the complete unacceptability or unsuitability of T. ni larvae for parasitism from day 11 on.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1975

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

Baldwin, W. F. and House, H. L.. 1952. Factors influencing the specific gravity of insect haemolymph. Can. Ent. 84: 131139.CrossRefGoogle Scholar
Barras, D. J., Wiygul, G., and Vinson, S. B.. 1969. Amino acids in the haemolymph of the tobacco budworm, Heliothis virescens Fab., as affected by its habitual parasite Cardiochiles nigriceps Viereck. Comp. Biochem. Physiol. 31: 707714.CrossRefGoogle Scholar
Beegle, C. C. 1971. Effect of a nuclear polyhedrosis virus on the relationship between Trichoplusia ni and the parasite, Hyposoter exiguae. Ph.D. Thesis, Univ. California, Riverside. 113 pp. Univ. Microfilms, Ann Arbor, Mich. (Diss. Abstr. 73–5906).Google Scholar
Chen, P. S. 1966. Amino acid and protein metabolism in insect development. Adv. Insect Physiol. 3: 53132.CrossRefGoogle Scholar
Corbet, S. A. 1968. The influence of Ephestia kuehniella on the development of its parasite Nemeritis canescens. J. exp. Biol. 48: 291304.CrossRefGoogle Scholar
Dahlman, D. L. 1969. Haemolymph specific gravity, soluble total protein and total solids of plant-reared, normal and parasitized diet-reared tobacco hornworm larvae. J. Insect Physiol. 15: 20752084.CrossRefGoogle Scholar
Doutt, R. L. 1963. Pathologies caused by insect parasites, pp. 393422. In teinhaus, Edward A. (Ed.), Insect pathology, an advanced treatise, Vol. 2. Academic Press, New York.Google Scholar
Fisher, R. C. 1971. Aspects of the physiology of entoparasitic Hymenoptera. Biol. Rev. 46: 243278.CrossRefGoogle Scholar
Fisher, R. C. and Ganesalingam, V. K.. 1970. Changes in the composition of host haemolymph after attack by an insect parasitoid. Nature 227: 191192.CrossRefGoogle ScholarPubMed
Guillot, F. S. and Vinson, S. B.. 1972. The role of the calyx and poison gland of Cardiochiles nigriceps in the host-parasitoid relationship. J. Insect Physiol. 18: 13151321.CrossRefGoogle Scholar
Jones, R. L. and Lewis, W. J.. 1971. Physiology of the host-parasite relationship between Heliothis zea and Microplitis croceipes. J. Insect Physiol. 17: 921927.CrossRefGoogle Scholar
Junnikkala, E. 1966. Effect of braconid parasitization on the nitrogen metabolism of Pieris brassicae L. Ann. Acad. Sci. Fenn. (Ser. A). IV. Biologica. No. 100, 83 pp.Google Scholar
Oser, B. L. (Ed.). 1965. Hawk's Physiological Chemistry, 14th ed. McGraw-Hill, New York. 1472 pp.Google Scholar
Patton, R. L. 1962. The specific gravity of insect blood and its application to physiological problems. J. Insect Physiol. 8: 537544.CrossRefGoogle Scholar
Puttler, B. 1961. Biology of Hyposoter exiguae (Hymenoptera: Ichneumonidae), a parasite of lepidopterous larvae. Ann. ent Soc. Am. 54: 2530.CrossRefGoogle Scholar
Salt, G. 1941. The effects of hosts upon their insect parasites. Biol. Rev. 16: 239264.CrossRefGoogle Scholar
Smilowitz, Z. 1971. Hemolymph proteins in developing cabbage looper larvae and pupae. Ann. ent Soc. Am. 64: 340343.CrossRefGoogle Scholar
Smilowitz, Z. 1973. Electrophoretic patterns in hemolymph protein of cabbage looper during development of the parasitoid Hyposoter exiguae. Ann. ent. Soc. Am. 66: 9399.CrossRefGoogle Scholar
Smilowitz, Z. and Iwantsch, G. F.. 1975. Relationships between the parasitoid Hyposoter exiguae and the cabbage looper, Trichoplusia ni: The effect of host age on ovipositional rate of the parasitoid and successful parasitism. Can. Ent. 107: 689694.CrossRefGoogle Scholar
Smilowitz, Z. and Smith, C. L.. 1970. Distributions and frequencies of weight of cabbage looper larvae reared on artificial diet. J. econ. Ent. 63: 11061107.CrossRefGoogle Scholar
Smith, C. L. 1974. Hemolymph proteins in developing Pieris rapae larvae parasitized by Apanteles glomeratus. M.S. Thesis, The Pennsylvania State University. 53 pp.Google Scholar
Snedecor, G. W. 1956. Statistical methods, 5th ed. Iowa State College Press, Ames.Google Scholar
Syme, P. D. and Green, G. W.. 1972. The effect of Orgilus obscurator (Hymenoptera: Braconidae) on the development of the European pine shoot moth (Lepidoptera: Olethreutidae). Can. Ent. 104: 523530.CrossRefGoogle Scholar
Vinson, S. B. 1972. Effect of the parasitoid, Campoletis sonorensis, on the growth of its host, Heliothis virescens. J. Insect Physiol. 18: 15091514.CrossRefGoogle Scholar
Vinson, S. B. and Barras, D. J.. 1970. Effects of the parasitoid, Cardiochiles nigriceps, on the growth, development, and tissues of Heliothis virescens. J. Insect Physiol. 16: 13291338.CrossRefGoogle Scholar
Wigglesworth, V. B. 1972. The principles of insect physiology, 7th ed. Chapman and Hall, London. 827 pp.CrossRefGoogle Scholar
Wyatt, G. R. 1961. The biochemistry of insect hemolymph. A. Rev. Ent. 6: 75102.CrossRefGoogle Scholar