Hostname: page-component-8448b6f56d-mp689 Total loading time: 0 Render date: 2024-04-23T07:57:16.667Z Has data issue: false hasContentIssue false
  • English
  • Français

Maize Yield Losses from Stemborers in Kenya

Published online by Cambridge University Press:  19 September 2011

Hugo De Groote
Hugo De Groote
Affiliation:
International Maize and Wheat Improvement Center (CIMMYT), P. O. Box 25171, Nairobi, Kenya E-mail: h.degroote@cgiar.org
Get access

Abstract

Maize is the major food crop in Kenya, where 2.3 million tonnes are produced annually to feed an estimated 28.6 million people (79 kg/person p.a.). Population growth in the country is high (2.9 % p.a.), resulting in increased pressure on arable land and, consequently, increased pest pressure on crops. Stemborers are one of the most important pests of maize. Previous research with artificial infestation established clear links between damage factors and yield losses. These results, however, cannot be extrapolated to estimate crop losses in farmers' fields under natural infestation. Due to lack of field data, farmers' (often subjective) estimates of losses under natural infestation and the incidence of infestation were used to estimate maize yield losses for each of Kenya's major agroecological zones. The yield loss was estimated to be 12.9 %, amounting to 0.39 million tonnes of maize, with an estimated value of US$ 76 million. High-potential areas have relatively low crop loss levels (10–12 %), while the low-potential areas have higher losses (15–21 %). Taking into account the higher yield of the former areas (more than 2.5 t/ha), the loss per hectare is remarkably constant, between 315 and 374 kg/ha, except for the dry mid-altitude zones, where losses total approximately 175 kg/ha. The value of these losses is estimated at US$ 61–75/ha and US$ 34/ha, respectively. Such estimates are useful for setting research and extension priorities.

Résumé

Le maïs est la principale culture au Kenya, avec 2,3 million de tonnes produites annuellement pour nourrir une population estimée à 28,6 million (79 kg/personne et par an). La croissance dela population dans le pays est élevée (2,9 % par an), avec pour conséquence une pression croissante sur les terres arables, et une augmentation des problèmes dues aux ravageurs. Les foreurs sont un des ravageurs les plus importants du maïs. Des études antérieures, effectuées à partir d'infestations artificielles ont établi une relation étroite entre les pertes des récoltes et les dégâts lies aux foreurs. Toutefois, ces résultats ne peuvent pas être utilisés pour estimer les pertes dans les champs des paysans sous infestation naturelle. Pour palier à l'absence des données de terrains, les estimations des pertes sous infestation naturelle (souvent subjectives) et l'incidence de l'infestation telles que founis par les paysans, ont été utilisés pour estimer les pertes en recolte de maïs dans chaque zone agroecologique importante du Kenya. Les pertes moyennes ont été estimées à 12.9 %, équivalent à 0.39 million de tonnes de maïs d'une valeur approximative de 76 million de dollars. Les régions à haut potentiel ont généralement un taux de pertes plus faible (10–12 %) que les régions à faible potentiels (15–21 %). En valeur absolue, et du fait de rendements plus élevés dans les regions a haut potentiel, les pertes par ha sont relativement constante entre 315 et 374 kg/ha, excepté dans la zone sèche d'altitude moyenne où les pertes totales sont de 175 kg/ha. La valeur de ces pertes est estimée à respectivement 61–75 dollars par hectare et 34 $/ha. Ce genre d'estimations est utiles à la détermination des priorités de recherche et de la vulgarisation agricole.

Keywords

stemborercrop lossmaizeKenyaforeurperte de recoltemaïsKenya
Type
Research Articles
Information
International Journal of Tropical Insect Science , Volume 22 , Issue 2 , June 2002 , pp. 89 - 96
Copyright
Copyright © ICIPE 2002

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

Ajala, S. O. and Saxena, K. N. (1994) Interrelationship among Chilo partellus (Swinhoe) damage parameters and their contribution to grain yield reduction in maize (Zea mays L.). Appl. Entornol. Zool, 29, 469–476.CrossRefGoogle Scholar
Alghali, A. M. (1992) Effects of cultivar, time and amount of Chilo partellus Swinhoe (Lepidoptera: Pyralidae) infestation on sorghum yield components in Kenya. Maydica 37, 371–376.Google Scholar
Aquino, P., Carrión, F. and Calvo, R. (1999) Selected Maize Statistics. Part 3 of CIMMYT 1997/98 World Maize Facts and Trends; Maize Production in Drought-stressed Environments: Technical Options and Research Resource Allocation. CIMMYT, Mexico, D.F.Google Scholar
Cardwell, K.F., Schulthess, F., Ndemah, R. and Ngoko, Z. (1997) A systems approach to assess crop health and maize yield losses due to pests and diseases in Cameroon. Agric. Ecosyst. Environ. 65, 33–47.CrossRefGoogle Scholar
Cochran, W. G. (1977) Sampling Techniques. John Wiley and Sons, New York. 428 pp.Google Scholar
De Groote, H. (1996) Optimal survey design for rural data collection in developing countries. Q. J. Int. Agric. 35, 163–175.Google Scholar
Gounou, S., Schulthess, F., Shanower, T., Hammond, W.N.O., Braima, H., Cudjoe, A.R. and Antwi, K.K. with Olaleye, I. (1994) Stem and ear borers of maize in Ghana. Plant Health Management Research Monograph No. 4. International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria.Google Scholar
Gebre-Amlak, A., Sigvald, R. and Petersson, J. (1989) The relationship between sowing date, infestation and damage by the maize stalk borer, Busseola fusca (Noctuidae), on maize in Awassa, Ethiopia. Trop. Pest Manage. 35, 143–145.CrossRefGoogle Scholar
Hassan, R. M. (Ed.) (1998) Maize Technology Development and Transfer: A GIS Application for Research Planning in Kenya. CAB International, Wallingford, UK/CIMMYT/KARI. 230 pp.CrossRefGoogle Scholar
Kumar, H. and Saxena, K. N. (1994) Infestation and damage on three maize cultivars by the stalk-borer Chilo partellus (Swinhoe) in relation to their yield in western Kenya. Insect Sci. Applic. 15, 331–335.Google Scholar
LeClerg, E. L. (1971) Field experiments for assessment of crop losses. In Crop Loss Assessment Methods. FAO Manual on the Evaluation and Prevention of Losses by Pests, Diseases and Weeds (Edited by Chiarappa, L.). FAO, Rome.Google Scholar
Mulaa, M. A. (1995) Evaluation of factors leading to rational pesticide use for the control of the maize stalk borer Busseola fusca in Trans Nzoia district, Kenya. PhD thesis, University of Wales, Cardiff.Google Scholar
Pingali, P.L. (ed.) (2001) CIMMYT 1999–2000 World Maize Facts and Trends. Meeting World Maize Needs; Technological Opportunities and Priorities for the Public Sector. CIMMYT, Mexico, D.F.60 pp.Google Scholar
Seshu Reddy, K. V. and Sum, K. O. S. (1991) Determination of economic injury of the stemborer, Chilo partellus (Swinhoe) in maize, Zea mays L. Insect Sci. Applic. 12, 269–274.Google Scholar
Seshu Reddy, K. V. and Sum, K. O. S. (1992) Yield-infestation relationship and determination of economic injury level of the stem-borer, Chilo partellus (Swinhoe) in three varieties of maize, Zea mays L. Maydica 37, 371–376.Google Scholar
Swaine, G. (1957) The maize and sorghum stalkborer Busseola fusca in peasant agriculture in Tanganyika territory. Bull. Entomol. Res. 48, 711–722.CrossRefGoogle Scholar
Walker, P. T. (1991a) Empirical models for predicting yield loss caused by one type of insect: The stemborers, pp. 133–137. In Crop Loss Assessment and Pest Management (Edited by Teng, P. S.). APS Press, The American Phytopathological Society, St Paul, Minnesota.Google Scholar
Walker, P. T. (1991b) Measurement of insect pest populations and injury, pp. 19–29. In Crop Loss Assessment and Pest Management (Edited by Teng, P. S.). APS Press, The American Phytopathological Society, St Paul, Minnesota.Google Scholar
Walker, P. T. (1991c) Quantifying the relationship between insect populations, damage, yield and economic thresholds, pp. 114–125. In Crop Loss Assessment and Pest Management (Edited by Teng, P. S.). APS Press, The American Phytopathological Society, St Paul, Minnesota.Google Scholar