Spatial Distribution of Maruca Testulalis Larvae on Cowpea, and a Sequential Sampling Plan for Estimating Larval Densities

  • S. Firempong
  • H. Magalit
Research Article


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.

Key Words

Maruca testulalis cowpea sequential sampling plan 


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.

Mots Cléfs

Maruca testulalis niébé méthode d’échantillonage séquentiel 


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Copyright information

© ICIPE-ICIPE Science Press 1990

Authors and Affiliations

  • S. Firempong
    • 1
  • H. Magalit
    • 1
  1. 1.The International Centre of Insect Physiology and Ecology (ICIPE)Mbita Point Field StationMbitaKenya

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