Comparative Evaluation of the Efficacy of Aqueous Neem Extract and Dipel 2x on Diamondback Moth, Plutella xylostella Linn., on Cabbage in Kenya

  • S. OkothEmail author
  • C. K. P. Ogol
  • M. Basimike
  • M. Varela
Research Article


The efficacy of neem kernel cake powder water extract (NKCP-WE) and Dipel 2x (Bacillus thuringiensis var. kurstakt) in controlling the diamondback moth (DBM), Plutella xylostella Linn. (Lepidoptera: Yponomeutidae), on cabbage was evaluated in screenhouse experiments. All concentrations of NKCP-WE tested were larvicidal and plants treated with 25 and 50 g/l NKCP-WE retained larvicidal activity for up to 2 weeks after application. The efficacy of 25 and 50 g/l NKCP-WE and 0.5 g/l Dipel 2x was compared by observing DBM development on the treated plants and yields of those plants. Dipel 2x-treated plants had less DBM larval infestation than the neem-treated plants but the latter treatment gave better yield. The implications of these observations are discussed.

Key Words

neem Azadirachta indica Dipel 2x Bacillus thuringiensis diamondback moth Plutella xylostella cabbage Kenya 


On a comparé l’efficacité de l’extrait aqueux de neem kernel (NKCP-WE) au Dipel 2x (Bacillus thuringiensis var. kurstaki), pour lutter contre le papillon de nuit à dos diamant (DBM) Plutella xylostella Linn. (Lepidoptera: Yponomeutidae). Toutes les concentrations de NKCP-WE testées ont exprimé une action larvicide et les plantes traitées avec 25 et 50 g/l de NKCP-WE ont gardé une activité larvicide pendant les deux semaines suivantes. L’efficacité des traitements à 25 g/l et 50 g/l de NKCP-WE et 0.5 g/l Dipel 2x a été comparé en observant le développement du DBM sur les plants traités et les rendements de ces plants. Les plants traités au ‘Dipel 2x’ ont hébergé moins de larves que les plants traites au ‘neem’ mais ce dernier a donné un meilleur rendement. Les implications de ces observations sont discutées.

Mots Clés

neem Azadirachta indica Dipel 2x Bacillus thuringiensis le papillon de nuit a diamant Plutella xylostella le chou Kenya 


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Copyright information

© ICIPE 2002

Authors and Affiliations

  • S. Okoth
    • 1
    Email author
  • C. K. P. Ogol
    • 2
  • M. Basimike
    • 2
  • M. Varela
    • 3
  1. 1.Kenya Trypanosomiasis Research InstituteKikuyuKenya
  2. 2.Department of ZoologyKenyatta UniversityNairobiKenya
  3. 3.GTZ IPM Horticulture ICIPENairobiKenya

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