Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-13T03:31:29.582Z Has data issue: false hasContentIssue false
  • English
  • Français

Spatial and temporal changes in the distribution of eggs of Heliothis armiger (Hübner) (Lepidoptera: Noctuidae) on Cotton in the Sudan Gezira

Published online by Cambridge University Press:  10 July 2009

Margaret J. Haggis
Margaret J. Haggis
Affiliation:
Centre for Overseas Pest Research, College House, Wrights Lane, London W8 5SJ, UK
Get access Rights & Permissions [Opens in a new window]

Abstract

To determine the extent to which the distribution of ovipositing Heliothis armiger (Hb.) might be ‘clumpy’ rather than random, the numbers of eggs on cotton throughout the 10 000 km2 Sudan Gezira were subjected to analyses of variance. It was found that at any time there was less variability within than between areas, highly significantly less for units of 600–700 km2. Within all areas, the numbers of eggs varied very significantly with time and many-fold increases in numbers of eggs occurred simultaneously over thousands of square kilometres. In every three-day period, there were two or more significantly different levels of infestation, each extending over areas ranging from a few hundred to several thousand square kilometres; the boundaries of such areas changed continuously, and no consistent differences or patterns were found. These findings suggest that redistribution of mobile populations of moths takes place over large distances. At all times there were areas with egg numbers below those considered economically serious; this has been utilised in new control strategy and tactics which have been effectively implemented experimentally. Larval spraying appeared also to reduce oviposition for at least three days and could in part account for some, but certainly not all, of the differences between areas.

Type
Original Articles
Information
Bulletin of Entomological Research , Volume 71 , Issue 2 , June 1981 , pp. 183 - 193
Copyright
Copyright © Cambridge University Press 1981

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

Allan, W. N. & Smith, R. J. (1948). Irrigation in the Sudan.— 593–632in Agriculture in the Sudan.— 974 pp. London, Oxford University Press.Google Scholar
Balla, A. N. (1970). American bollworm in the Gezira and Managil..—pp. 281–292in Siddiq, M. A. & Hughes, L. C. (Eds). Cotton growth in the Gezira environment (A symposium to mark the 50th Anniversary of the Gezira Research Station).—318 pp.Wad Medani, Sudan, Agricultural Research Corporation.Google Scholar
Cowland, J. W. (1935). Experimental work carried out by the staff of the Gezira Entomological Section during the season 1933/34..—Rep. Gezira Agric. Res. Serv., Sudan 1934, 99–118.Google Scholar
El Tigani, M. & El Tayib, M. (1978). Development of crop protection in the Sudan, with special reference to application of ULV and water-based insecticides..—pp. 149–163in 4th Scientific Conference: Chemicalisation of plant production in the tropics and subtropics. Vol. 3, 237 pp. Leipzig, DDR, Institut für tropische Landwirtschaft, Karl-Marx Universität..Google Scholar
Haggis, M. J. (1973). Conference report. Insect Flight and its Relevance to the Strategy of Control of Insect Pests of Cotton in the Sudan Gezira..—Pest Artic. & News Summ. 19, 419–421.Google Scholar
Haggis, H. J. (1978 a). Distribution of American bollworm eggs in the Sudan Gezira: spatial and temporal changes and their relation to weather..—pp. 24–67. in Proceedings of the Third Seminar on the Strategy for Cotton Pest Control in the Sudan..—357 pp. Basle, Switzerland, Ciba-Geigy.Google Scholar
Haggis, M. J. (1978 b). Conference report. Third Ciba-Geigy Seminar on the Strategy for Cotton Pest Control in the Sudan, Basle, May 1978..—Pest Artic. & News Summ. 24, 531–533.Google Scholar
Hassan, H. M. (1970). Progress in chemical control of pests..—pp. 232–246in Siddiq, M. A. & Hughes, L. C. (Eds). Cotton growth in the Gezira environment. (A symposium to mark the 50th Anniversary of the Gezira Research Station).—318 pp. Wad Medani, Sudan, Agricultural Research Corporation.Google Scholar
Johnson, C. G. (1969). Migration and dispersal of insects by flight..—763 pp. London, Methuen.Google Scholar
Joyce, R. J. V. (1955). Cotton spraying in the Sudan Gezira. I and II..—Pl. Prot. Bull. F.A.O. 3, 86–92, 97–103.Google Scholar
Joyce, R. J. V. (1975).The implications to control strategy of the observed flight activity of pest species in the Sudan Gezira..—(15 pp.) in Proceedings of a Seminar on Strategy for Cotton Pest Control in the Sudan Gezira. Wad Medani, Sudan, Ciba-Geigy..Google Scholar
Joyce, R. J. V. (1976 a).Sequential aerial spraying of cotton at ULV rates in the Sudan Gezira as a contribution to synchronised chemical application over the area occupied by the pest population..—pp.47–54in Proceedings of the Fifth International Agricultural Aviation Congress.-.—403 pp. UK, International Agricultural Aviation Centre.Google Scholar
Joyce, R. J. V. (1976 b).Insect flight in relation to problems of pest control.—pp. 135–155in Rainey, R. C. (Ed.). Insect flight.—287 pp. Oxford, Blackwell Scientific.Google Scholar
Joyce, R. J. V. (1978).Yield response of Gossypium barbadense in the Sudan Gezira to aerial spraying at ULV rates with Nuvacron 40R.—pp. 229–242in Proceedings of the Third Seminar on Strategy for Cotton Pest Control in the Sudan.—357 pp. Basle, Switzerland, Ciba-Geigy..Google Scholar
Pearson, E. O. (1958). The insect pests of cotton in tropical Africa..— 355 pp. London, Emp. Cott. Gr. Corp. & Commonw. Inst. Ent..Google Scholar
Rainey, R. C. (1976).Flight behaviour and features of the atmospheric environment.—pp.75–112in Rainey, R. C. (Ed.). Insect flight.—287 pp. Oxford, Blackwell Scientific.Google Scholar
Topper, C. (1978 a).The incidence of Heliothis armigera larvae and adults on groundnuts and sorghum and the prediction of oviposition on cotton..—pp. 17–33in Proceedings of the Third Seminar on Strategy for Cotton Pest Control in the Sudan..—357 pp. Basle, Switzerland, Ciba-Geigy.Google Scholar
Topper, C. (1978 b).The effect of commercial spraying against eggs and larvae on adult Heliothis armigera, 1977.—pp. 243–259in Proceedings of the Third Seminar on Strategy for Cotton Pest Control in the Sudan.—357 pp. Basle, Switzerland, Ciba-Geigy..Google Scholar