Academe Research Journals

International Journal of Agricultural Science Research

Full Length Research Paper

Evaluating the insecticidal potential of aqueous plant extracts from Zanthoxylum zanthoxyloides and Anacardium occidentale against insect pest complexes of cabbage in an open field experiment.

Angelina Fathia Osabutey ¹, Vincent Eziah², Thomas Buxton³, Ebenezer Oduro Owusu⁴

¹African Regional Postgraduate Programme in Insect Science (ARPPIS) University of Ghana, Legon PMB Ghana

²Department of Crop Science, University of Ghana, Legon, P. O. Box LG 25, Legon, Ghana

³Forest and Horticultural Crops Research centre, University of Ghana, Legon, P.O. Box LG 25, Legon, Ghana

⁴Department of Animal Biology and Conservation Science, University of Ghana, Legon, P. O. Box LG 25, Legon, Ghana

*Corresponding author. E-mail: ofathiaangelina@gmail.com

Accepted 21 June 2018

Abstract

Cabbage production and consumption have drastically increased in both rural and urban dwellings in Ghana. Although the plant is susceptible to insect pests, the tendency to produce quality with low insecticide cabbage head has been a problem yet to be fully resolved. The study was to evaluate the insecticidal activity of some Ghanaian botanicals: Zanthoxylum zanthoxyloides leaf and stem bark, Anacardium occidentale leaf and nutshell against insect pest complexes of cabbage in an open field conditions during 2013 major and minor rainy seasons. Infestation level of reduced P xylostella and B. brassicae was significantly lower on botanical treated plot, synthetic plots than the contol plots in both seasons. The level of predators and parasitoids did not differ significantly on botanical treated plot and control plot. Botanical treated plots recorded high cabbage heads weight and diameter with less damage thereby increasing the number of marketable heads on botanical treated plots than the control plots.

Keywords: Zanthoxylum zanthoxyloides, Anarcardium occidentale Plutella xylostella, Brevicornye brassicae