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Losses in yield due to pests in tropical crops and their value in policy decision-making

Published online by Cambridge University Press:  19 September 2011

P. T. Walker
P. T. Walker
Affiliation:
10 Cambridge Road, Salisbury, Wiltshire SPI 3BW, England
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Abstract

Recent developments in the assessment and collection of yield loss data due to pests are discussed. The information is needed for decision-making on resource allocation, on pest management, crop production planning and crop improvement. The difficulties in accurate loss assessment include lack of information on the distribution of pests in space and time, the difference between research and farmers yields, how much control has been used, and changes in crop resistance and in pest status. Sources of data are described and examples of losses in a number of tropical crops. The difficulties met in using losses to justify research and crop improvement projects, with particular reference to banana pests in Tanzania and cassava pests in Ghana, include the absence of reliable data, the selection of a base-line yield and the effects of other causes of loss.

Résumé

Les développements récents dans l'évaluation et la collection des données des pertes de production causées par les insectes nuisibles sont discutés. Ces données sont nécessaires pour faire les décisions sur la répartition des ressources, sur la lutte integrée et sur l'amélioration des cultures. Les difficultés rencontrées sont le défaut de renseignements sur le distribution des insectes en espace et en temps, la différence entre les rendements sur la ferme et experimentales, le degré de lutte chimique, et les changements dans la résistance des cultures et de la situation des insectes nuisibles.

Les origines des données et examples des pertes de quelques cultures tropicales sont presentés. Les difficultés rencontrées en utiliser les données pour justifier des projets d'amélioration des bananiers en Tanzanie et la manioc en Ghana comprendent l'absence des données sériouses, la sélection d'une ligne base de rendement, et les effets d'autres causes de perte.

Keywords

Crop losspestseconomic effectsyield lossbanana pestsCosmopolitescassava pestsPhenacoccusMononychellusPertes de productioneffets économiquesinsectes nuisibles aux bananiers et manioc
Type
Symposium VI: Economie Impact of Insects in the Tropics
Information
International Journal of Tropical Insect Science , Volume 8 , Issue 4-5-6: Recent Advances in Research on Tropical Entomology , December 1987 , pp. 665 - 671
Copyright
Copyright © ICIPE 1987

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