Improved Small-scale Vegetable Production and Productivity in Africa with the Use of Agricultural Nets

Almost 33% of the sub-Saharan Africa population, close to 200 million people, is undernourished.  One of the contributing factors is the low fruit and vegetable consumption, which is estimated at 22% to 82% below the intake value threshold of 400 g/day recommended by the World Health Organization and Food and Agricultural Organization. This severe malnutrition leads to many chronic diseases among populations. Most vegetable growers in the region are smallholders with limited access to improved germplasm, pest and disease control tools, and improved crop production technologies. Vegetable farms are routinely devastated by pests, diseases, unreliable rains, and extended drought conditions. The goal of this partnership is to develop low-cost strategies for pest and micro-climate management in vegetable production systems.  Studies were conducted in Benin and Kenya to test the impact of agro-nets on pest exclusion and vegetable productivity using cabbage and tomato as model crops.  Tomato and cabbage seedlings or transplants were grown either in the open air or under netting.  Mesh size was 0.4 mm for transplant production and 0.9 mm for field production. The impact of netting on air temperature and relative humidity varied with location and growing season. Under hot and humid growing conditions (Benin), the air temperature under the nets was too high suggesting the need for nets with large mesh size. In cooler areas (Egerton, Kenya); the temperature increase under the net was beneficial for crop development. The use of nets improved seed germination, seedling establishment, and seedling growth in all growing conditions. The nets were beneficial for cabbage production with a reduction in pesticide input and showed good potential for tomato production. This technology needs more study to develop procedures for climate control inside the nets as well as for irrigation and management of pests that develop inside the net. This project was funded by the United States Agency for International Development (USAID) under Award No. EPP-A-00-09-00004 through Horticulture CRSP at UC Davis. For more information on the project visit http://www.bionetagro.org/