Hostname: page-component-5c6d5d7d68-wtssw Total loading time: 0 Render date: 2024-08-19T03:31:30.689Z Has data issue: false hasContentIssue false

Effect of cassava variety on the biology of Bemisia afer (Priesner & Hosny) (Hemiptera: Aleyrodidae)

Published online by Cambridge University Press:  19 September 2011

D. C. Munthali
Affiliation:
University of Malawi, P. O. Box 278, Zomba
Get access

Abstract

The biology of Bemisia afer (Prisner & Hosny) reared in clip cages on leaves of 15 varieties of cassava, Manihotesculenta (Crantz)(Euphorbiaceae) was studied under field conditions during the cold months of June–August and during the warm months of September–October. Both variety and time of the year significantly affected the developmental period, the rate of population increase and the mortality.

The longest mean developmental period (59.5 days) occurred on the MH108 leaves during the cold months (at 20°C and 62.9% r.h.), while the shortest (27.1 days) was on the Kithekere variety during the warm months (at 25°C and 53% r.h.).

The pest population increased most rapidly on MH84 (at 5.4 eggs per female per day) and slowest on the Nigerian 3057/1 (at 0.9 eggs per female per day). The mortality of the pest indicated that Chitembwere had the greatest killing power (K = 2.555) and Nigerian 3057/1 had the least (K = 0.0760).

The combined use of the developmental periods, rate of population Increase and mortality indicated that Gomani was the most resistant while Kithekere was the least resistant variety to B. afer. Other varieties with high resistance properties included MH108, Chitembwere and Mbundumali. Of the three biological characteristics used, the developmental period was the most powerful while the rate of population increase was the least.

Pubescence of a cassava variety was only weakly associated with resistance to B. afer (r = 0.48) suggesting that other factors are more responsible for resistance to this pest than hairiness.

Résumé

La biologie de Bemisia afer (Priesner & Hosny) élevée dans des cages en plastique sur les feuilles de manioc de quinze variétés, Manihot esculenta (Crantz) (Euphorbiaceae) était étudié sous les conditions de terrain pendant la saison froide du mois de juin au mois d'aôut et pendant des mois chauds de septembre à octobre. La variéte ainsi que le temps de l'année ont influencé de façon significative la période de développement, le taux de croissance de la population et la mortalité.

La moyenne la plus longue de la période de développement (de 59.5 jours) a eu lieu sur les feuilles de MH108 pendant les mois froids (à 20°C et 62.9% h.r.), alors que la plus courte (de 27.1 jours) était sur la variété de Kithekere pendant les mois chauds (à 25°C et 53% h.r.).

La population parasitaire augmenta le plus rapidement sur MH84 (à 5.4 oeufs par femelle par jour) et augmenta le moins vite sur le Nigerian 3057'1 (à 0.9 oeufs par femelle par jour). La mortalité des insectes indiquait que Chitembwere avait le plus grand pouvoir de tuer (K = 2.555) et le Nigerian 3057/1 avait le pouvoir le plus faible (K = 0.760).

L'utilisation à la fois des périodes développementales, le taux de croissance de la population et la mortalité indiquèrent que Gomani était la plus résistante alors que Kithekere était la variété la moins résistante à B. afer. D'autres variétés avec de hautes propriétés de résistance comprenait MH108, Chitembwere et Mbundumali. Des trois caractéristiques biologiques employées, la période développementale était la plus puissante tandis que le taux de la croissance de la population était la motndre.

Les poils d'une varlété de cassave n'était que faiblement associés à la résistance à B. afer (r = 0.48) suggérant le fait que d'autres facteurs sont plus responsables pour la resistance centre ce parasite que la présence des poils.

Type
Research Articles
Copyright
Copyright © ICIPE 1992

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

Gerling, D. (1985) Parasitoids attacking Bemisia tabaci (Hom.: Aleyrodidae) in Eastern Africa. Entomophaga 30, 163165.CrossRefGoogle Scholar
Githunguri, C. M., Ndong'a, M. F. O. and Amadalo, B. A. (1984) Cassava production and its constraints in Kenya. In Integrated Pest Management of Cassava Green Mite (Edited by Greathead, A. H., Markham, R. H., Murphy, R. J., Murphy, S. T. and Robertson, I. A. D.), pp. 7579. Proc. Training Workshop, 30 April-4 May 1984 Nairobi, Kenya.Google Scholar
Hahn, S. K. (1989) Breeding cassava for pestresistance with specific reference to the cassava mealybug and green mite. In Root Crops and Low-Input Agriculture (Edited by Aivarez, M. N. and Hahn, S. K.), pp. 7680, Proc. Third Eastern and Southern Africa Regional Workshop on Root Crops, 7–11 December 1987, Mzuzu, Malawi.Google Scholar
Makame, M. and Said, M. R. (1984) Cassava production in Tanzania—Zanzibar. In Integrated Pest Management of Cassava Green Mite (Edited by Greathead, A. H., Markham, R. H., Murphy, R. J., Murphy, S. T. and Robertson, I. A. D.), pp. 107111, Proc. Regional Training Workshop. 30 April-4 May 1984, Nairobi, Kenya.Google Scholar
Martin, J. H. (1987) An identification guide to common whitefly pest species of the world (Homoptera, Aleyrodidae). Trop. Pest Manage. 33, 298322.CrossRefGoogle Scholar
Muimba-Kankolongo, A., Muyolo, G., Mahungu, N. M. and Pandy, S.J. (1986) Strategies of Programme National Manioc (PRONAM) of Zaire and screening cassava for resistance to major diseases. In Tropical Root Crops: Root Crops and the African Food Crisis (Edited by Terry, E. R., Akoroda, M. O. and Arene, O. B.), pp. 109112. Proc. Third Triennial Symposium of the International Society for Tropical Root Crops, 17–23 August 1986, Oweri, Nigeria.Google Scholar
Mulindangabo, J. and Birandano, B. (1984) Some problems of cassava production in Rwanda. In Integrated Pest Management of Cassava Green Mite (Edited by Greathead, A. H., Markham, R. H., Murphy, R. J., Murphy, S. T. and Robertson, I. A. D.), pp. 95100. Proc. Regional Training Workshop, 30 April-4 May 1984, Nairobi, Kenya.Google Scholar
Otim-Nape, G. W. and Igoot, D. (1986) Effect of cultural practices on the African cassava mosaic disease and its vector, Bemisia tabaci. In Tropical Root Crops: Root Crops and the African Food Crisis (Edited by Terry, E. R., Akaroda, M. O. and Arene, O. B.), pp. 105108. Proc. of the Third Triennial Symposium of the International Society for Tropical Root Crops, 17–23 August 1986, Oweri, Nigeria.Google Scholar
Robertson, I. A. D. (1985) Cassava/Whitefly project: Part of Crop Virology Project R3177: Final Report. ODA, London.Google Scholar
Robertson, I. A. D. (1987) The whitefly Bemisia tabaci (Gennadius) as a vector of African cassava mosaic virus at the Kenya Coast and ways in which the yield losses in cassava Manihot esculenta (Crantz) caused by the virus can be reduced. Insect Sci. Applic. 8, 797801.Google Scholar
Sauti, R. F. N. (1982) Utilisation and production constraints of cassava in Malawi. In Integrated Pest Management of Cassava Green Mite (Edited by Greathead, A. H., Markham, R. H., Murphy, R. J., Murphy, S. T. and Robertson, I. A. D.), pp. 8186. Proc. of a Regional Workshop, 30 April–4 May 1984, Nairobi, Kenya.Google Scholar