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Dispersion pattern of adults and vertical distribution of larvae of Smicronyx guineanus Voss and Smicronyx umbrinus Hustache (Coleoptera: Curculionidae) on Striga hermonthica (Del.) Benth (Scrophulariaceae)

Published online by Cambridge University Press:  19 September 2011

Doulaye Traore
Affiliation:
Institut d'Études et de Recherches Agricoles (I.N.E.R.A.), 03 B.P. 7192 Ouagadougou 03, Burkina Faso, West Africa
Charles Vincent*
Affiliation:
Centre de Recherches et de Développement en Horticulture Agriculture et Agro-Alimentaire Canada, 430 Boul. Gouin, Saint-Jean-sur-Richelieu, Qué. Canada J3B 3E6
Robin K. Stewart
Affiliation:
Department of Natural Resource Sciences, Macdonald Campus of McGill University, 21111 Lakeshore Road, Ste-Anne-de-Bellevue, Quebec, Canada H9X 3V9
*
* Corresponding author.
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Abstract

Populations of adults of Smicronyx guineanus Voss and Smicronyx umbrinus Hustache were sampled on the witchweed Striga hermonthica (Del.) Benth, in Burkina Faso. Samples were taken at four localities in 1991 and at one locality in 1992 and 1993 using a Univac portable suction sampler, beginning at emergence time of the adult weevils, to assess their dispersion patterns and the optimum sample size for Smicronyx. Sampling was done weekly by placing the 60-mm-diameter suction cone on a Striga plant until it was about 5 cm above the ground. Smicronyx adults on S. hermonthica were aggregated. A sample size of 20 and 126 units provided a 25 and 10% precision level respectively at six Smicronyx adults per sampling unit. A chart was designed which could be useful for determining the level of precision attainable at various densities of Smicronyx adults for sampling and monitoring programmes. Larval vertical distribution of Smicronyx was described. Striga plants were stratified with respect to distance from the base and categories were designated as upper, central and lower parts. Results indicated that Smicronyx larvae were located in the upper stratum of the witchweed where they made galls and destroyed large numbers of seeds.

Résumé

Des études ont été conduites dans des champs infestés de Striga hermonthica (Del.) Benth pour échantillonner les adultes de Smicronyx guineanus Voss et Smicronyx umbrinus Hustache au Burkina Faso. Les échantillons ont été pris avec un aspirateur portable à insectes (Univac), dans quatre localités en 1991, une en 1992 et 1993 dès émergence des charançons afin de déterminer la distribution spatiale et de calculer la taille optimum d'échantillon. Une distribution groupée des adultes de Smicronyx a été observée sur S. hermonthica. Vingt unités d'échantillonnage ont procuré un niveau de précision sur la base de 6 spécimens d'insectes par unité. Un diagramme a été mis au point en tenant compte de la relation entre la densité et la degré de précision à des niveaux fixes. La distribution verticale des larves de Smicronyx a été décrite. Les plantes de Striga ont été divisées en trois catégories à partir de la base et désignées parties supérieure, centrale et inférieure. Les résultats indiquèrent que les larves du charançon étaient localisées dans la partie supérieure de la plante parasite où elles provoquaient des galles et détruisent ainsi de grandes quantités de graines.

Type
Research Articles
Copyright
Copyright © ICIPE 1994

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References

REFERENCES

Abacus Concepts Inc. (1989) Super ANOVA, v. 1.1, Accessible General Linear Modeling. Berkeley, California.Google Scholar
Abacus Concepts Inc. (1992) Stat View, v. 4.0, The Ultimate Integrated Data Analyses and Presentation System for Macintosh. Berkeley, California.Google Scholar
Bashir, M. O. (1987) The potential for biological control of witchweeds. In Parasitic Weeds in Agriculture (Edited by Musselman, L. J.), pp. 183206. CRC Press Inc., Boca Raton, Florida.Google Scholar
Bashir, M. O. and Musselman, L. J. (1984) Some natural enemies of Striga hermonthica in the Sudan. Trop. Pest Manage. 30, 211212.CrossRefGoogle Scholar
Cardwell, K. F., Smith, J., Weber, G. and Awad, A. (1991) Framework for orientation of Striga research at IITA. In Proc. V Int. Symp. Par. Weeds (Edited by Ransom, J. K., Musselman, L. J., Worsham, A. D. and Parker, C.), pp. 503511. CIMMYT, Nairobi, Kenya.Google Scholar
Ekbom, B. S. (1985) Spatial distribution of Rhopalosiphum padi (L.) (Homoptera: Aphididae) in spring cereals in Sweden and its importance in sampling. Environ. Entomol. 14, 312316.CrossRefGoogle Scholar
Elliott, N. C. and Kieckhefer, R. W. (1986) Cereal aphid populations in winter wheat: Spatial distributions and sampling with fixed levels of precision. Environ. Entomol. 15, 954958.CrossRefGoogle Scholar
Greathead, D. J. (1984) The natural enemies of Striga spp. and the prospects for their utilization as biological control agents. In Striga—Biology and Control. Proceedings of an international workshop held at Dakar, Senegal, November 1983, pp. 133160. ICSU Press Symposium Series No. 2.Google Scholar
Greathead, D. J. and Milner, J. E. D. (1971) A survey of Striga spp. (Scrophulariaceae) and their insect natural enemies in East Africa with a discussion on the possibilities of biological control. Trop. Agric. 48, 111124.Google Scholar
Iwao, S. (1968) A new regression method for analyzing the aggregation pattern of animal population. Res. Popul. Ecol. 10, 120.CrossRefGoogle Scholar
Iwao, S. (1977) The m-m statistics as a comprehensive method for analyzing spatial patterns of biological populations and its application to sampling problems. In Studies on Methods Estimating Population Density, Biomass and Productivity in Terrestrial Animals (Edited by Morisita, M.), pp. 2146. University of Tokyo Press, Japan.Google Scholar
Iwao, S. and Kuno, E. (1971) An approach to the analysis of aggregation pattern in biological populations. In Statistical Ecology (Edited by Patil, G. P., Pielou, E. C. and Waters, W. E.), vol. 1, pp. 461513. Pennsylvania State University, University Park.Google Scholar
Karandinos, M. G. (1976) Optimum sample size and some comments on some published formulae. Bull. Entomol. Soc. Am. 22, 417421.Google Scholar
Khan, M. Q. and Murthy, D. V. (1955) Smicronyx albovariegatus Faust (Curculionidae: Coleoptera) on Striga spp. Indian J. Entomol. 17, 362.Google Scholar
Lagoke, S. T. O., Parkinson, V. and Agunbiade, R. M. (1991) Parasitic weeds and control methods in Africa. In Proceedings of the International Workshop on Combating Striga in Africa (Edited by Kim, S. K.), pp. 314. 22–24 August 1988. IITA, Ibadan, Nigeria.Google Scholar
Llyod, M. (1967) Mean crowding. J. Anim. Ecol. 36, 130.CrossRefGoogle Scholar
Markham, R. H. (1985) Possibilities for the biological control of Striga species in the Sahel. Permanent Interstate Committee for Drought Control in the Sahel. Mission report, 20 pp.Google Scholar
Mboob, S. S. (1986) A regional programme for West and Central Africa. In Improved Management in Africa: Proceedings of the FAO/OAU All-Africa Government Consultation on Striga Control (Edited by Robson, T. O. and Broad, H. R.), pp. 191194. 20–24 October 1986, Maroua, Cameroon.Google Scholar
Monro, J. (1967) The exploitation and conservation of resources by populations of insects. J. Anim. Ecol. 36, 531547.CrossRefGoogle Scholar
Musselman, L. J. (1983) The need for consideration of biocontrol in Striga. In Proc. of the 2nd Int. Workshop of Striga (Edited by Vrinda, K.), pp. 109110. 5–8 October 1981, Ouagadougou, Upper Volta.Google Scholar
Ogborn, J. (1984) Research priorities in agronomy. In Striga—Biology and Control. Proceedings of an international workshop held at Dakar, Senegal, November 1983, pp. 195212. ICSU Press Symposium Series No. 2.Google Scholar
Osmond, C. B. and Monro, J. (1981) Prickly pear. In Plants and Man (Edited by Carr, D. J. and Carr, S. M.), pp. 194222. Academic Press, Sydney.Google Scholar
Ouédraogo, O. (1986) Striga in Burkina Faso. In Improved Management in Africa: Proc. of the FAO/OUA All-Africa Government Consultation on Striga Control (Edited by Robson, T. O. and Broad, H. R.), pp. 3436. 20–24 October 1986, Maroua, Cameroon.Google Scholar
Paré, J. (1993) Aspects de la dynamique de la formation de la graine chez le Striga (Scrophulariaceae) parasite des céréales tropicales. Thèse de doctorat d'État ès sciences naturelles. Université Pierre et Marie Curie-Paris VI.Google Scholar
Parker, C. and Riches, C. R. (1993) Parasitic Weeds of the World: Biology and Control. CAB International. Castlefield Press, Kettering, Northants, UK.Google Scholar
Sauerborn, J. (1991) The economic importance of the phytoparasites Orobanche and Striga. In Proc. V Int. Symp. Par. Weeds (Edited by Ransom, J. K., Musselman, L. J., Worsham, A. D. and Parker, C.), pp. 137143. CIMMYT, Nairobi, Kenya.Google Scholar
Smith, M. C., Holt, J. and Webb, M. (1993) Population model of the parasitic weed Striga hermonthica (Scrophulariaceae) to investigate the potential of Smicronyx umbrinus (Coleoptera: Curculionidae) for biological control in Mali. Crop Protection 12, 471476.CrossRefGoogle Scholar
Southwood, T. R. E. (1978) Ecological Methods. Chapman and Hall, London.Google Scholar
Stewart, G. (1990) Witchweed: A parasitic weed of grain crops. Outlook Agric. 19, 115119.CrossRefGoogle Scholar
Traoré, D. (1994) Bionomics of Smicronyx guineanus Voss and Sm. umbrinus Hustache (Coleoptera: Curculionidae), potential biocontrol agents of Striga hermonthica (Del.) Benth. Ph.D. thesis, Macdonald Campus, McGill University.Google Scholar
Traoré, D., Ouédraogo, O. and Kambou, G. (1990) Rapport Annuel: Projet Canado-Burkinabé de Protection des Végétaux, Laboratoire de Kamboinsé. Ouagadougou. 72 pp.Google Scholar
Traoré, D., Vincent, C. and Séré, A. (1991) Prospects for biological control of Striga (witchweed) in Burkina Faso. In Proc. V Int. Symp. Par. Weeds (Edited by Ransom, J. K., Musselman, L. J., Worsham, A. D. and Parker, C.), p. 328. CIMMYT, Nairobi, Kenya.Google Scholar
Ward, S. A., Rabbinge, R. and Mantel, W. P. (1985) The use of incidence counts for population estimation of aphid populations. 1. Minimum sample size for required accuracy. Neth. J. Plant Pathol. 91, 9399.CrossRefGoogle Scholar
Williams, C. N. and Caswell, G. H. (1959) An insect attacking Striga. Nature 184, 1668.CrossRefGoogle Scholar