Integrated pest management in vegetable production: a guide for extension workers in West Africa

Indigenous and exotic vegetables are central to most nutrition, food security and poverty reduction programmes around the world. However, in most of West Africa, the economic opportunities offered by vegetables are often undermined by production and trade constraints (i.e. pest damage, inappropriate pesticide usage, absence of environmental safeguard policies and/or stringent food safety standards). Extension workers and, in places, farmers groups and local community organizations, are working towards helping farmers to increase their yields in sustainable ways that create wealth and reduce the risks to productivity. All too often, extension workers do not know the cause of common pest problems in the crops they work with. Pest problems usually arise when the biological, ecological and sociological processes which underpin agriculture are disrupted. This guide helps to fill that information gap. It is one of many responses by the International Institute of Tropical Agriculture (IITA) which enables such workers to develop and use technologies. It focuses on accurate identification and better understanding of biodiversity in the development and application of Integrated Pest Management (IPM) options against vegetable pests. IPM is a knowledge-intensive approach to enhance profitability of agricultural systems, while minimizing threats to human health and the environment. The technical knowledge and skills in this guide can be used to look for, develop and apply effective vegetable IPM options. The IPM options outlined here are in harmony with the environment, sustainable, simple to apply, and cheap to maintain. The guide addresses IITA’s strategic aim of increasing the quality and usefulness of IPM research in support of reducing food security and poverty. It draws heavily on IITA’s experiences in Africa, with a particular emphasis on vegetable agroecosystems in Benin. Given the substantial economic costs of pest infestations in vegetable agroecosystems, the use of this guide in Africa is expected to improve incomes and overall agricultural productivity in the long-term. Peter Hartmann Director General International Institute of Tropical Agriculture March 2010 ForewordThis guide has been produced by the International Institute of Tropical Agriculture (IITA) and Institut National des Recherches Agricoles du Bénin (INRAB), Cotonou, Benin, with support from the CGIAR Systemwide Program on Integrated Pest Management (SP-IPM), to improve the quality and usefulness of pest management research. This publication was part funded by the ACP-EU Technical Centre for Agricultural and Rural Cooperation (CTA)

Gestion intégrée des nuisibles en production maraîchère : Guide pour les agents de vulgarisation en Afrique de l'Ouest

Les parasites se manifestent généralement en cas de bouleversement des processus biologiques, écologiques et sociologiques qui sous-tendent l'agriculture. En plus d'apporter des informations sur la gestion durable des menaces biotiques portées à une production végétale saine, ce guide suggère également des manières d'enseigner et de diffuser des pratiques de lutte antiparasitaire intégrée auprès d'un public plus large. Exceptionnellement bien illustré par des illustrations, tableaux et photos, cet ouvrage se promet d'être une référence précieuse pour les professionnels sur le terrain, les agents de vulgarisation, les techniciens, les étudiants et les scientifiques

Insecticide dissipation from soil and plant surfaces in tropical horticulture of southern Benin, West Africa

In Sub-Saharan Africa, horticulture provides livelihood opportunities for millions of people, especiallyin urban and peri-urban areas. Although the vegetable agroecosystems are often characterized byintensive pesticide use, risks resulting therefrom are largely unknown under tropical horticulturalconditions. The objective of this study therefore was to study the fate of pesticides in two representativehorticultural soils (Acrisol and Arenosol) and plants (Solanum macrocarponL.) after field applicationand thus to gain first insight on environmental persistence and dispersion of typical insecticides used invegetable horticulture in Benin, West Africa. On plant surfaces, dissipation was rapid with half livesranging from 2 to 87 h (a-endosulfan <b-endosulfan < deltamethrin). Soil dissipation was considerablyslower than dissipation from plant surfaces with half-lives ranging from 3 (diazinon) to 74 d (totalendosulfan), but persistence of pesticides in soil was still reduced compared to temperate climates.Nevertheless, for deltamethrin and endosulfan, a tendency for mid-term accumulation in soil uponrepeated applications was observed. The soil and plant surface concentrations of the metaboliteendosulfan sulfate increased during the entire trial period, indicating that this compound is a potentiallong-term pollutant even in tropical environments

Potential of Beauveria bassiana and Metarhizium anisopliae isolates from Benin to control Plutella xylostella L. (Lepidoptera: Plutellidae)

Published OnlineDiamondback moth (DBM), Plutella xylostello L., is the main pest limiting cabbage production in Benin. Inthe search for biological agents to control the pest, eight isolates of the entomopathogenic fungiBeauveria bassiana and Metarhizium anisopliae indigenous to Benin were screened for virulence againstlarvae of the insect. The B. bassianc isolates tested were Bba14, Bba5644, 8ba5645, 8ba5653, Bba5654,and Bba5655, and M. anisopliae isolates were Ma178 and Ma182. The isolate Bba5653 caused 94%mortality of DBM larvae, and the mortality was significantly higher than that caused by any of the otherisolates. Cabbage yield was 44.1 tlha for plots treated with water formulation of Bba5653 at 1 kg conidiapowder (CP) per hectare and 41.9 t/ha for plots treated with emulsion formulation of Bba5653 at same CPdose. Each of the yields was approximately threefold higher than the yield in plots treated with theinsecticide bifenthrin or in untreated plots. In water formulations, 1 kg/ha of the conidia powder ofBba5653 reduced DBM populations at about the same rate as did 0.75 kg and 0.5 kgCP/ha, but signifi-cantly more than did 0.25 kgCP/ha

Management of rootknot nematodes on Solanum macrocarpon using botanicals in Benin

Root-knot nematode (RKN), Meloidogyne spp. is an economically important pest of the traditional leafy vegetable, Solanum macrocarpon L., in Benin. In the search for IPM options, the effect of 5, 20, 35 and 50 g of dried skin peels of cassava storage roots (CP) and orange fruits (OP) each on incidence and damage severity of RKNs and biomass of S. macrocarpon was compared to that of 1, 2, 3 and 4 mg of commercially available fungal nematicide Paecilomyces lilacinus (Pl) and the chemical nematicide Rugby10 applied at 0.4 gpotted S. macrocarpon. In the field experiment CP and OP applied at 840 g and 1200 g1.4 m x 1 m bed; Pl at 75 g and 96 gbed and Rugby10 at 12 gbed. The botanicals, Pl and Rugby10 were mulched into soil, which was later planted with S. macrocarpon seedlings from nematode-free nurseries. In the potted plant experiment, pots were each inoculated with 1500 juveniles of RKNs. In the study, the botanicals showed promise against RKNs, especially when applied at highest doses. In pots, OP applied at 50 gpot and Rugby10 reduced percentage roots with galls significantly more than did control treatment. CP and OP at 50 gpot were as efficient as Pl and Rugby10 in reducing nematode population density. CP at 50 gpot had higher biomass than potted plants with Pl at dose inferior to 4 mgpot, Rugby10 and control plants. In field, OP, CP and Pl when applied at highest doses significantly reduced percentage roots with galls and nematode population density and increased plant biomass as compared to control

Extending Integrated Pest Management to indigenous vegetables

Leafy gboma (Solanum macrocarpon) and amaranths (Amaranthus sp.) are the two most important indigenous vegetables in the urban and peri-urban areas of Benin. IITA’s vegetable project has generated extensive baseline information on diversity, distribution and economic importance of pests of the crops; identified abuse and misuse of chemical pesticides in the vegetable sector; isolated suitable strains of entomopathogenic fungi as biopesticides against foliage feeders; and identified botanicals against root knot nematodes. Among 435 project-trained vegetable producers (30% women), 81 of them serve as community organizers to assist their colleagues incorporate research findings into vegetable production, increase local ownership and wider adoption of IPM options. Private-sector participation is required to assist move proven biologically-based IPM options from experimental to commercial level