Box 4: Cost of training smallholder farmers in green agriculture practices
In a recent report on organic agriculture, the ADB concluded that the cost of transition for farmers to move from conventional agricultural practices to organic practices, including the cost of certification, was approximately US$ 77-170 per farmer for an average farm size of 1 hectare (ADB 2010). Training costs were estimated at US$ 6-14/farmer. These are fairly modest compared to the overall investment required for extricating farmers from poverty (an approximate investment of US$ 554-880, according to the World Bank (2008a). Yet there remain additional costs. These are the costs of enabling policies that allow research and development, market linkages and creating incentive systems on the demand and supply side. These costs cannot be understated and obviously require multilateral and bilateral support in the international arena.
suppress biotic stresses and combat pests, during the past few decades there has been a substantial increase of private and, to a much lesser degree, publicly-funded efforts to develop genetically modified (GM) crops to overcome pest and weed problems. After initial success, there is growing evidence of an evolving resistance to GMO crops by many pests and weeds. The IAASTD report (2009) recommended that research on the ecological, economic and social questions concerning the widespread application of GM crops should be increased, particularly in the public R&D sector, whose scientific advances could be more broadly and equitably available for use in developing countries.
Table 2 presents selected evidence on the costs and benefits of plant and animal health management strategies (PAHM). Plant and animal health management practices reduce farmers’ input costs and their exposure to hazardous chemicals while effectively supporting productive crop yields. Plant and animal health management practices also reduce or replace the use of chemical insecticides that often kill non-targeted insects. Many insect species killed as collateral damage from such insecticides have beneficial environmental and agricultural roles as pollinators and as predators of other pests, and are part of the natural food chain.
wide range of low-cost natural bio-control practices that improve the ability of plants and livestock to resist and
Strategy Intercropping Crop and country
Maize intercropped with Desmodium uncinatum, East Africa (Khan et al. 2008).
Costs
Most costs are associated with additional labour costs.
Evidence presented in Table 2 show that all PAHM interventions are highly profitable. Intercropping is a particularly useful strategy with high benefit to cost
Benefits
Maize grain yield increases ranged from double to five times in plots using push-pull strategies compared to monocropped plots. Levels of pests reduced significantly and were completely eliminated in some. (Reductions ranged from 75% to 99%).
Pest Management
The wasp predator to fight the cassava bug in Africa (Norgaard 1988). Cocoa in Cameroon (Dieu et al. 2006).
The cost of introducing the wasp across cassava growing countries in Africa (1978- 2003) is estimated at US$ 14.8 million. This includes research and distribution costs. For cocoa, IPM meant that labour costs increased by 14%. But total production costs decreased by 11% due to reduced use of fungicides.
Bio-pesticides
Fungal spores in fighting grasshopper in Benin, maize and cassava, cowpea and groundnuts crops (De Groote et al. 2001).
Estimated cost for effective intervention was US$ 4/ha.
Introducing the wasp predator introduction helped avoid 60% of the losses caused by the cassava mealy bug. In cocoa plantation, IPM reduced cost of fungicides by 39%.
Trends in revenues and profits after including additional costs of greening
Benefit to cost ratio is 2.5 to 1 using the push-pull strategy. Gross revenues with push-pull were US$ 424-880/ha compared to 82-132/ha using a mono- maize cultivation strategy.
Benefit cost ratio of 149 to 1 for the wasp predator strategy, across all cassava growing countries in Africa, 1978-2003. Reduced costs of fungicides in the context of obtaining similar yields can lead to increase in profitability for the farmers.
Cumulative mortality of grasshoppers after 20 days of spraying was over 90%.
Bio-pesticides have small costs and major benefits of avoided damage. Yield losses due to grasshoppers can reach 90% in cowpea and 33% in maize.
Table 2: Selected evidence on benefits and costs of plant and animal health management 52