Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-24T13:29:27.840Z Has data issue: false hasContentIssue false

Determination of the Number of Instars of the Silkworm Anaphe venata Butler (Lepidoptera: Notodontidae)

Published online by Cambridge University Press:  19 September 2011

M. O. Ashiru
Affiliation:
Forestry Research Institute of Nigeria, Entomology Section, P.M.B. 5054, Ibadan, Nigeria
Get access

Abstract

The number of instars in the silkworm Anaphe venata was determined using three methods namely: (1) direct observation of cast exuviae by larvae reared through the entire larval stage, (2) use of frequency distributions of head capsule lengths and widths taken from larvae representative of the entire larval stage of the species and (3) morphological observations and examinations of larval segments and anal plates. Seven instars were observed for A. venata. The most reliable method was the direct observation of cast exuviae by larvae reared through the entire larval stage. It is further suggested that either the method of histograms of head capsules or examination of larval segments and anal plates be used to supplement this method for better reliability.

Résumé

Le nombre d'instars dans le ver à soie Anaphe venata était déterminé en utilisant trois méthodes-notamment (1) L'observation directe de jet (exuvise) par les larves qui sont élévées entierement a travers l'étape larvaire. (2) L'emploi des distributions de fréquence de longeur et de largeur de capsule de tête pris des représentatives des larves dans toute l'étape larvaire des espèces et (3) les observations et inspections morphologiques des segments larvaires et des plaques anales.

Sept instars étaient observés pour A. venata. La methode le plus sûr était l'observation directe de jet exuvise par les larves élévées à travers l'étape larvaire toute entière.

Il est proposé que la method d'histogram de capsule de tête ni l'inspections morphologiques des segments larvaires et des plaques anal peut être utilisée pour complétes cette méthode-pour mieux solidité.

Type
Research Articles
Copyright
Copyright © ICIPE 1988

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

Albrecht, F. O. (1955) La densite des populations et la croissance chez Schistocerca gregaria (Forsk.) et Nomadacris septemfasciata (Serv.); la mue d'adjustment. J. Agric. Trop. Bot. appl. 11, 109192.Google Scholar
Ashiru, M. O. (1986) The bionomics and socio-economic importance of Anaphe venata Butler (Lepidoptera: Notodontidae), a defoliator of Triplochiton scleroxylon K. schum. Ph.D. thesis, Department of Agricultural Biology, University of Ibadan.Google Scholar
Browne, F. G. (1968) Pests and diseases of forest plantation trees. Clarendon Press, Oxford, pp. 49 and 1155.Google Scholar
Butler, A. (1878) Descriptions of some new genera and species of Lepidoptera from old Calabar and Madagascar Ann. Mag. Nat. Hist. 2, 455465.CrossRefGoogle Scholar
Daramola, A. M. (1974) A review on the pests of Cola species in West Africa. Nigerian J. Ent. 1, 2129.Google Scholar
Dyar, H. G. (1890) The number of moults of lepidopterous larvae. Psyche 5, 420422.CrossRefGoogle Scholar
Ene, J. C. (1963) Insects and Man in West Africa. Ibadan University Press.Google Scholar
Ene (1965) The distribution and bionomics of the Anaphe silk moths of Nigeria. Proc. Sci. Assoc. Nig. 6, 5761.Google Scholar
Fox, R. C., Anderson, S. C., Garner, S. C. and Walker, A. I. (1972) Larval headcapsules of the Nantucket pine tip moth. Ann. Ent. Soc. Am. 65, 513514.CrossRefGoogle Scholar
Gaines, J. C. and Campbell, F. L. (1935) Dyar's rule as related to the number of instars of the corn ear worm, Heliothis obsoleta (Fab.) collected in the field. Ann. Ent. Soc. Am. 28, 445461.CrossRefGoogle Scholar
Golding, F. D. (1942) The wild silkworms of Nigeria, Fm. For. 3, 3540.Google Scholar
Hoxie, R. P. and Wellso, S. G. (1974) Cereal leaf beetle instars and sex, defined by larval head capsule widths. Ann. Ent. Soc. Am. 67, 183186.CrossRefGoogle Scholar
Jolly, M. S., Sen, S. K., Sonwalkar, T. N. and Prasad, G. K. (1979) Non-mulberry silks. F.A.O. Agric. Serv. Bull. Rome 29.Google Scholar
Jones, N. and Kudler, J. (1971) A survey of fruiting of Triplochiton scleroxylon K. schum and the insects made in 1969–1970. Ghana. J. Sci. 10, 93106.Google Scholar
Kennedy, J. D. (1936) Forest flora of Southern Nigeria, Lagos. Government Printing Department.Google Scholar
Kishi, Y. (1971) Reconsideration of the method to measure the larval instars by use of the frequency distribution of headcapsule widths or lengths. Can. Ent. 103, 10111015.CrossRefGoogle Scholar
Long, D. B. (1953) Effects of population density on larvae of lepidoptera. Trans. R. Ent. Soc. Lond. 104, 543584.CrossRefGoogle Scholar
Parker, D. L. and Meyer, M. W. (1972) Biology of a leaf roller, Archips negundamus, in Utah (Lepidoptera, Tortricidae) Ann. Ent. Soc. Am. 65, 14151418.CrossRefGoogle Scholar
Peterson, A. and Haeussler, C. J. (1928) Some observations on the number of larval instars of the oriental peach moth, Laspeyresia molesta Busck. J. Econ. Ent. 21, 843852.CrossRefGoogle Scholar
Pomeroy, A. W. (1923) The production of Anaphe silk in Nigeria for export and its possible economic value. 2nd Ann. Bull. Nig. Agric. Dep.Google Scholar
Roberts, H. (1969) Forest insects of Nigeria, with notes on their biology and distribution. Comm. For. Inst. paper No. 44 p. 5.Google Scholar
Schmidt, F. H., Campbell, R. K. and Trotter, S. J. Jr (1977) Errors in determining instar numbers through head capsule measurements of a Lepidopteran—a laboratory study and critique. Ann. Ent. Soc. Am. 70, 750756.CrossRefGoogle Scholar
Schmidt, F. H. and Lauer, W. L. (1977) Developmental polymorphism in Christoneura spp. (Lepidoptera: Tortricidae). Ann. Ent. Soc. Am. 70, 112118.CrossRefGoogle Scholar
Taylor, R. L. (1931) On ‘Dyar's rule’ and its application to sawfly larvae. Ann. Ento. Soc. Am. 24, 451–66.CrossRefGoogle Scholar
Teissier, G. (1936) La loi Dyar et la Croissance des Arthropodes. Livre jubil, Bouvier, Paris, 335342.Google Scholar
Vanderwerker, G. K. and Kulman, H. M. (1974) Stadium and sex determination of yellow-headed spruce sawfly larvae, Pikonema alaskensis C. Ann. Ent. Soc. Am. 67, 2931.CrossRefGoogle Scholar
Wigglesworth, V. B. (1972) The principles of insect physiology. Chapman and Hall. London.CrossRefGoogle Scholar
Wilson, L. G. (1974) Life history and habits of a leaf tier, Aroga argutiola (Lepidoptera: Gelechiidae) on sweet fern in Michigan. Can. Ent. 106, 991994.CrossRefGoogle Scholar