The efficacy of a mosquito netting to protect cabbages, Brassica oleracea L., against pests was investigated in field trials in Benin, West Africa. A polyester net covered the plants at night by using a wood armature. The net was removed during the day to prevent overheating and excessive shade, both problems of insect-proof screens used under tropical conditions. The number of all lepidopteran larvae with netting protection and foliar insecticide sprays was significantly lower than the unprotected control. The number of diamondback moth, Plutella xylostella (L.), was significantly lower with netting protection compared with foliar insecticide sprays and control. Netting treated with deltamethrin gave total protection of young plants against the aphid Lipaphis erysimi (Kaltenbach). At harvest, the number of marketable cabbages protected with untreated netting was significantly higher compared with the production with foliar insecticide sprays. The protection of cabbages with netting can be an economically viable method. Considering the price of cabbages on local markets (US dollars 1/unit), the net returns per 100 m2 were US dollars 247 by using netting, US dollars 149 by using insecticides, and US dollars 117 for controls. The net returns for using netting are based on replacing the netting each crop cycle. But netting can be reused several times, depending upon conditions, increasing the profit margin. The netting protection may be an alternative to the growing unsustainable practices of vegetable cropping in peri-urban areas of tropical countries.

Domestication and Utilization. Traditional vegetables in many African rural areas are an important part of the daily diet and economy but have been poorly documented until recently. We undertook a survey in Benin on the diversity and patterns of use of traditional vegetables by 18 sociolinguistic groups in the three major phytogeographical regions. Major groups include the Yoruba-Nagot, Fon, Bariba, Adja, Cotafon, and Ditammari. Focus groups and field visits were conducted in 49 villages. Species richness at the country level and in phytogeographical regions was estimated using species accumulation curves. Our results indicated that 245 species belonging to 62 families are used as vegetable resources all over the country. The most frequently used families include Amaranthaceae, Asteraceae, Cucurbitaceae, and Leguminoseae. About 80% of collected vegetables are wild resources; only 19% were clearly under cultivation. Herbs were the most widely consumed life form. The Guinean and the Sudanian regions exhibit similar species richness while in the Sudano-Guinean region vegetable richness is higher. The use of a species as a vegetable depends not only on socio-cultural attributes but also on geographical occurrence. Based on this inventory, we identified needs for further research and activities for both the conservation and promotion of traditional vegetables.Diversité, Distribution Géographiques, et Mode de Consommation des Légumes Traditionnels dans les Groupes Sociolinguistiques du Bénin: Implications pour la Domestication et l'Utilisation des Ressources. Les légumes traditionnels représentent une part importante dans le régime alimentaire quotidien et l'économie des communautés rurales en Afrique. Cependant, ils ont été négligés par la recherche jusqu'à récemment. Au Bénin, nous avons entrepris un inventaire de la diversité et des types d'usage des légumes traditionnels au niveau de 18 groupes sociolinguistiques, dans les trois grandes zones phytogéographiques du pays. Les groupes linguistiques enquêtés comprennent les Yoruba-Nagot, Fon, Bariba, Adja, Cotafon, et Ditammari. Des entretiens de groupes et visites de terrain ont été organisés dans 49 villages. La richesse spécifique au niveau national et au niveau des zones phytogéographiques a été estimée par la méthode de courbes d'accumulation spécifique. Nos résultats indiquent que 245 espèces appartenant à 62 familles de plantes sont exploitées comme légumes au niveau national. Les familles fréquemment utilisées sont les Amaranthaceae, Asteraceae, Cucurbitaceae, et les Leguminoseae. Environ 80% des légumes collectés sont des ressources sauvages et seulement 19% sont clairement cultivés. Les herbacées représentent la majeur partie des légumes. Les zones Guinéenne et Soudanienne présentent des richesses spécifiques similaires, tandis que la richesse spécifique de légumes est supérieure dans la zone Soudano-Guinéenne. L'utilisation d'une espèce comme légume dépend 1

Protecting vegetables with a screen in peri-urban areas of tropical countries could reduce or even prevent often indiscriminate insecticide applications by small-scale farmers. The advantages of such an approach are protection of human health by reducing insecticide sprays, reducing environmental pollution from insecticide residues and increasing effectiveness of crop protection. Tunnel screens are well adapted to farmers cultivating intensively on small plots. Two trials were conducted to test the ability of screened tunnels to protect Brassica oleracea crops. The first was carried out onstation and the second in partnership with three farmers in Cotonou, Benin, West Africa. Tunnel screens impregnated with deltamethrin were found to be particularly well adapted to protect young plants in seedling nurseries against infestations by the aphid Lipaphis erysimi (Kaltenbach). The number of diamondback moth Plutella xylostella (Linnaeus) and borer Hellula undalis (Fabricius) on cabbages protected with the tunnel screen was significantly lower than that of plots conventionally treated with insecticides. The tunnel screen was not efficient against the armyworm Spodoptera littoralis (Boisduval) which laid eggs on the screen. After planting out, the use of a temporary screen from 1700 to 0900 h gave better control against pests than the use of a permanent screen possibly due to the impact of natural enemies during the day. The field trials showed that the protection of cabbage with a tunnel screen could be an economically viable method. The costs of pesticides are on average US$ 45 per 100 m 2 for one crop cycle compared with US$ 24 per 100 m 2 for tunnel screen material (assuming that this material can be used for 10 consecutive crop cycles). In addition, there are environmental benefits from a reduction of pesticide use. Farmers will have to cope with the initial investment for the screen material, which is, however, very cost-effective and locally available. Tunnel screens for vegetable protection can be easily combined with other integrated pest-management techniques.

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The efficacy of a mosquito netting to protect cabbages, Brassica oleracea L., against pests was investigated in field trials in Benin, West Africa. A polyester net covered the plants at night by using a wood armature. The net was removed during the day to prevent overheating and excessive shade, both problems of insect-proof screens used under tropical conditions. The number of all lepidopteran larvae with netting protection and foliar insecticide sprays was significantly lower than the unprotected control. The number of diamondback moth, Plutella xylostella (L.), was significantly lower with netting protection compared with foliar insecticide sprays and control. Netting treated with deltamethrin gave total protection of young plants against the aphid Lipaphis erysimi (Kaltenbach). At harvest, the number of marketable cabbages protected with untreated netting was significantly higher compared with the production with foliar insecticide sprays. The protection of cabbages with netting can be an economically viable method. Considering the price of cabbages on local markets (US dollars 1/unit), the net returns per 100 m2 were US dollars 247 by using netting, US dollars 149 by using insecticides, and US dollars 117 for controls. The net returns for using netting are based on replacing the netting each crop cycle. But netting can be reused several times, depending upon conditions, increasing the profit margin. The netting protection may be an alternative to the growing unsustainable practices of vegetable cropping in peri-urban areas of tropical countries.

Background: Environmental heterogeneity, emerging pathogens and limited access to financial and agricultural inputs prevent farmers from producing consistent crop yields in many developing countries. Yield instability impedes establishment of processing and export industries, thereby inhibiting economic development. Modern varieties offer significant increases in yield stability. Results:A deeply collaborative, multi-national germplasm trialing network was established in West Africa to identify tomato varieties well adapted to each country and mobilize those varieties into local seed distribution networks alongside an integrated pest management program. Research partners in seven West African countries evaluated over 100 tomato varieties for resistance to tomato leaf curl disease (ToLCD). Using biotechnology, the identity and distribution of the key viruses (begomoviruses) causing ToLCD in these countries were identified, and a vector-independent inoculation method (agroinoculation) was developed. The trials identified a set of high-performing varieties with resistance. Agroinoculation with the three prevalent begomoviruses confirmed resistance. Conclusions:These trial results fulfill the new Economic Community of West African States harmonized seed regulation policy, which requires at least 2 years of national performance trials prior to commercialization of a tomato variety. To compete with a rapidly expanding canned tomato import industry, West African growers need to increase productivity and processing capacity; therefore, we also assessed processing and export trade data for fresh and processed tomatoes from each of the seven countries.

We investigated if eco-friendly nets (EFNs) are a viable and acceptable alternative to extremely high levels of insecticide use in vegetable production. Using a choice experiment, we found that vegetable producing farmers in Benin preferred all of the characteristics of EFNs except the higher labor requirements. The nets had been distributed in a trial phase for free but in the long run farmers would need to purchase the EFNs. The break-even point for investing in nets was found to vary with the lifespan of EFNs, their purchase price and potential health benefits from avoiding large quantities of insecticides. To break even the nets need to be used for at least two production cycles. To overcome risk-averse farmer's reluctance to adopt EFNs we propose a credit and warranty scheme along with the purchase of the nets. The study's findings can guide the implementation of EFNs in other African countries as part of integrated pest management with global benefits for the environment and human health.

Cabbage (Brassicaceae) is one of the most frequently consumed exotic vegetables in Benin and also the most affected by insects. To meet growing food demand, farmers rely heavily on synthetic pesticides that are harmful for themselves, consumers and the environment. Integrated pest management has been proposed as the means to improve vegetable productivity and quality in many developing countries. One approach is to substitute pesticides with physical barriers to insects, like nets. Here, we assess consumers' OPEN ACCESSEnvironments 2015, 2 450 perceptions about cabbage and their purchasing behavior towards cabbage that was produced using these nets in two major cities in Benin. Results indicate that consumers are aware of the health risks associated with intensive use of pesticides but were not able to recognize the quality difference between cabbage produced under nets from those using pesticides. All consumers were willing to pay a price premium for cabbage with minimized pesticides residues compared with conventionally produced cabbage, the average premium being 38%. Women, older, highly educated consumers and those able to distinguish cabbage qualities were willing to pay the most. We suggest that farmers will obtain higher prices if their production of cabbage with preferred characteristics is accompanied by an improved marketing strategy.