Journal of Food, Agriculture and Environment




Vol 8, Issue 2,2010
Online ISSN: 1459-0263
Print ISSN: 1459-0255


Extracts of tropical African spices are active against Plutella xylostella


Author(s):

Nelson N. Ntonifor 1*, Irene Mueller-Harvey 2, Ron H. Brown 2

Recieved Date: 2009-12-16, Accepted Date: 2010-04-02

Abstract:

Extracts from Piper guineenseAframomum meleguetaAframomum citratum and Afrostyrax kamerunensis were investigated for their antifeedant, lethal and developmental effects against Plutella xylostella larvae through laboratory dual-choice tests and topical application. Water and ethanol extracts of P. guineense were dose-dependent antifeedants at concentrations ≥300 and 500 ppm, respectively, whilst methanol extracts required ≥1,000 ppm. Methanol and hexane extracts of A. melegueta acted at ≥100 ppm and water extracts at ≥300 ppm, but ethanol extracts were deterring feeding only slightly at ≥1,000 ppm. Hexane and methanol extracts of A. citratum inhibited feeding at ≥300 ppm and water extracts did so at ≥500 ppm. None of the Afrostyrax kamerunensis extracts deterred feeding at any of the concentrations tested. No mortality was observed at any of the concentrations after topical application of the extracts on the larvae. However, the effects on larval development varied with extract concentration and larval age. Ingestion of the water and ethanol extracts of P. guineense caused 100% mortality of second instars at ≥100 ppm two to three days after infestation (DAI). Methanol and water extracts of A. melegueta and A. citratum, respectively, achieved ≥80% mortality of larvae at concentrations of ≥500 ppm and ≥1,000 ppm, respectively. With third instars, the mortalities were significantly lower; however, the P. guineense water or ethanol extracts caused 100% mortality two to four DAI. Larvae that survived till pupation had significantly longer larval periods compared with the control after application of A. melegueta extracts. We concluded that potent extracts from Aframomum meleguetaAframomum citratum and especially P. guineense could be used as complementary measures in the management of P. xylostella by subsistence farmers.

Keywords:

Piper guineense, Aframomum meleguata, Aframomum citratum, Afrostyrax kamerunensis, crude extracts, biological activity, diamondback moth


Journal: Journal of Food, Agriculture and Environment
Year: 2010
Volume: 8
Issue: 2
Category: Agriculture
Pages: 498-502


Full text for Subscribers
Information:

Note to users

The requested document is freely available only to subscribers/registered users with an online subscription to the Journal of Food, Agriculture & Environment. If you have set up a personal subscription to this title please enter your user name and password. All abstracts are available for free.

Article purchasing

If you like to purchase this specific document such as article, review or this journal issue, contact us. Specify the title of the article or review, issue, number, volume and date of the publication. Software and compilation, Science & Technology, all rights reserved. Your use of this website details or service is governed by terms of use. Authors are invited to check from time to time news or information.


Purchase this Article:   20 Purchase PDF Order Reprints for 15

Share this article :