Participatory Evaluation of Productivity, Fertility Management, and Dissemination of Irrigated Exotic Vegetables in the Sahel, West Africa
We conducted on-farm participatory experiments and activities for 3 years at three sites in the Fakara district of western Niger to demonstrate, verify, and evaluate crop productivity due to fertilizer application, economic benefits, and the dissemination of crop technology. We tested combinations of manure and mineral fertilizer on 13 exotic vegetables: bell pepper, cabbage, carrot, chili, eggplant, lettuce, melon, onion, potato, pumpkin, sweet potato, tomato, and zucchini. Farmers’ selectivity was evaluated as the number of plots that farmers selected to carry out their own trials. The application of 110 kg·N/ha manure plus 13.7 kg·N/ha mineral fertilizer increased overall vegetable yields by 161% (P < 0.01). The improvement of soil fertility increased the yield of subsequent rainfed millet by 124% (P < 0.05). Less-experienced female farmers could afford to grow cabbage, onion, lettuce, potato, and pumpkin, which yielded 4.8 - 11.4 t/ha fresh weight. Daily management by women in the vegetable gardens gave regular opportunities to chat and thus disseminate the technology.