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Spatial distribution of Maruca testulalis larvae on cowpea, and a sequential sampling plan for estimating larval densities

Published online by Cambridge University Press:  19 September 2011

S. Firempong
Affiliation:
The International Centre of Insect Physiology and Ecology (ICIPE), Mbita Point Field Station, P.O. Box 30, Mbita, Kenya
H. Magalit
Affiliation:
The International Centre of Insect Physiology and Ecology (ICIPE), Mbita Point Field Station, P.O. Box 30, Mbita, Kenya
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Abstract

Larvae of Maruca testulalis were found to be randomly dispersed on flowers of cowpea cultivar Vita 1. Three models based on Taylor's power law, Lloyd's mean crowding and the negative binomial were tested to find out the best fit for developing a sequential sampling plan for this pod borer. Taylor's power law model gave the best fit whilst the negative binomial gave the least. A sequential sampling plan and a table of optimum sample size for use in the field were therefore developed, based on the random distribution.

Résumé

Sur les fleurs de niébé, cultivar Vita 1, les chenilles de Maruca testulalis se répartisent au hasard. Trois modèles basées sur “Taylor's power law”, “Lloyd's mean crowding” et la binomiale négative ont été testées dans le but de dévélopper une méthode d'échantillonage séquentiel de ces foreurs de gousses. “Taylor's power law” s'est montré le plus approprié. C'est pourquoi une méthode d'échantillonage séquentiel et une table de nombre d'échantillonage optimal ont été dévéloppée pour les travaux de tenain.

Type
Research Articles
Copyright
Copyright © ICIPE 1990

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References

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