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An analysis of the population dynamics of the Jamaican sugar-cane pest Saccharosydne saccharivora (Westw.) (Hom., Delphacidae)

Published online by Cambridge University Press:  10 July 2009

J. R Metcalfe
J. R Metcalfe
Affiliation:
Sugar Manufacturer' Association (of Jamaica) Ltd., Mandeville, Jamaica
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Extract

The Varley & Gradwell method of population analysis is applied to data on populations of Saccharosydne saccharivora (Westw.), comprising 51 generations from 21 fields, obtained in Jamaica in 1961–62. Populations were estimated at five points in each generation, namely, maximum potential natality, and numbers of eggs laid, instar 1, peak instars 3–5, and of normal reproducing adults. Taking maximum potential natality as the first point in each life budget, graphical analysis showed that the key factor was mortality between instar 1 and reproducing adults or between peak instars 3–5 and reproducing adults. Reduced fecundity, due to submaximal leaf nitrogen, was density independent or possibly inversely density dependent; one egg parasite, Tetrastichus sp., was inversely density dependent while another, Anagrus flaveolus Waterh., and an undetermined egg mortality factor were density independent; parasitism of nymphs and presumably adults also by Stenocranophilus quadratus Pierce was density dependent, and was Considered to be the only regulating factor. The key factor was density independent, and it is concluded that, of the separate mortality factors contained within it, dispersal of adults is the most important. This itself depends on crop characters which could be altered by selective breeding or agricultural practice.

Type
Original Articles
Information
Bulletin of Entomological Research , Volume 62 , Issue 1 , July 1972 , pp. 73 - 85
Copyright
Copyright © Cambridge University Press 1972

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References

Greathead, D. J. (1970). A study of the host relations of Halictophagus pontifex Fox (Strepsiptera), a parasite of Cercopidae (Hem., Aphrophorinae), in Uganda.—Bull. ent. Res. 60, 33–42.CrossRefGoogle Scholar
Luck, R. F. (1971). An appraisal of two methods of analyzing insect life tables.—Can. Ent. 103, 1261–1271.CrossRefGoogle Scholar
Metcalfe, J. R. (1969). Studies on the biology of the sugar-cane pest Saccharosydne saccharivora (Westw.) (Hom., Delphacidae).—Bull. ent. Res. 59, 393–408.CrossRefGoogle Scholar
Metcalfe, J. R. (1970). Studies on the effect of the nutrient status of sugar-cane on the fecundity of Saccharosydne saccharivocra (Westw.) (Hom., Delphacidae).—Bull. ent. Res. 60, 309–325.CrossRefGoogle ScholarPubMed
Metcalfe, J. R. (1971). Observations on the ecology of Saccharosydne saccharivora (Westw.) (Hom., Delphacidae) in Jamaican sugar-cane fields.—Bull. ent. Res. 60, 565–597.CrossRefGoogle ScholarPubMed
Southwood, T. R. E. (1967). The interpretation of population changes.—J. Anim. Ecol. 36, 519–529.CrossRefGoogle Scholar
Sugar Manufacturer' Association (of Jamaica) (1963). Rep. Res. Dep. Sug. Mfrs' Ass. Jamaica, 23.Google Scholar
Varley, G. C. & Gradwell, G. R. (1960). Key factors in population studies.—J. Anim. Ecol. 29, 399–401.CrossRefGoogle Scholar
Varley, G. C. & Gradwell, G. R. (1968). Population models for the winter moth.—Symp. R. ent. Soc. Lond. 4, 132–142.Google Scholar