almost 90% of African farmers currently practice diversified production, a more pragmatic approach may be to optimize the farming systems already in place by exploiting the particular advantages of these systems (IAC, 2004). Indeed, many technologies in SSA remain “on the shelf”, in part because they are relevant to specialized rather than diversified systems and in part because they are not relevant to the particular environmental characteristics of the region. For development and sustainability goals to be reached, new technologies will need to address the sustainability of the agricultural systems themselves and the impact they have on non-agricultural ecosystems that provide services important for improving livelihoods and the environment.

 There is a growing consensus that collaborative research with local farmers and groups, and putting local people’s perspectives at the center of research efforts is the best way forward, particularly for small-scale diversified farms. Yet there is little evidence as to whether such approaches are likely to be successful in the future, and knowledge on how to operationalize them (Omamo, 2003). Many of the recommendations are not evidence based, but rather advocate new and intuitively appealing approaches. However, SSA’s poor agricultural performance relative to other regions suggests that a change is needed. Given the criticisms of earlier AKST developments (technologies that are inadequately responsive to farmer needs and based on unrealistic results from experimental stations), more inclusive non-linear approaches may be more successful.

5.2.1.1 Participatory approaches to R&D
Participatory approaches are increasingly accepted by many stakeholders as a way of increasing the likelihood that farming solutions will be adopted by farmers (Ashby et al., 2000; Ngugi, 2005.) Participatory plant breeding (PPB) and farmer participatory research processes decentralize control over the research agenda and permit a broader set of stakeholders to become involved in research, thereby also addressing the different needs of men and women for technical innovation. The paradigm of involving farmers in research is based on strong evidence (Pretty and Hine, 2001) that enhancing farmers’ technical skills and research capabilities and involving them as decision makers in the technology development process results in innovations that are more responsive to their priorities, needs and constraints. This is an important strategy in making research more demand-driven and responsive to the growing needs of farmers and can contribute to the development of technologies that meet the needs and priorities of farmers. Many of the participatory approaches that have been proposed or implemented reflect the diversity of farmers’ fields and socioeconomic circumstances and illustrate clear differences between controlled scientific off-farm experiments and the reality of farming in much of SSA. The development and adoption of a diverse range of technologies for water harvesting and conservation in East Africa has been attributed in part to the adoption of community-based participatory approaches in place of the traditional top-down approach to technology research and extension (Lundgren, 1993).

 In general participatory approaches have not been proven as yet to be more effective than earlier approaches

(Farrington and Martin, 1988; Bentley, 1994), and may be constrained by the existing institutional structures in many SSA countries, including the NARS system (Hall and Nahdy, 1999). A number of specific drawbacks to and criticisms of farmer-led and participatory approaches have been identified. First, there has been a tendency for these approaches to emphasize food security, with insufficient attention paid to development of the value chain through marketed and valueadded goods. Increasing the involvement of the private sector and recognizing the role of the market could increase the relevance and further adoption of appropriate technologies (Heemskerk et al., 2003). Second, participatory approaches have typically been used for applied and adaptive research and technology transfer, and so they have not as yet been a source of significant scientific data (Probst et al., 2003). This is in part due to the lack of scientists involved in longer-term participatory research, which is a consequence of a rewards system based on the generation of data at meso and macro levels (Probst et al., 2003).

 It may not be possible to have statistically valid results from participatory trials because of the high variance in farmers’ fields. Rather, the aim might be to get results that are satisfactory within the context of a particular production system that, again, are difficult to publish in more traditional scientific journals (Mavedzenge et al., 1999). Third, participatory and integrated approaches tend to be local, often incorporating specific local and traditional knowledge, and so are difficult to scale up and are often costly relative to their impact. Where approaches have proven to be locally successful when working with a farmer group or a community, a key issue is to understand how participatory approaches can be adapted and used with large numbers of farmers to achieve wider impact, while still retaining the expected human and social capital benefits of participation. Finally, even in situations where research benefits from supply-led approaches, the needs, demands and circumstances of farmers in SSA can inform the research directions (Rothschild, 2005). For example, there are many examples of successful integrated pest and disease management projects, as well as work on climate change adaptation that have been led by scientists but have incorporated a participatory approach.

 One outstanding factor that has received little attention in the participatory development discourse as it pertains to agricultural extension in SSA is that of language. Projects and agencies concerned with agricultural development tend to function in languages different from those that farmers and rural communities use in their livelihoods and for communicating local knowledge (Chaudenson, 2004). It is not possible to say that this is a cause for the poor performance of agriculture, but it is a factor that is underresearched. SSA is the only region where formal education and government services function in languages different from the first languages of almost the entire citizenry. There is anecdotal evidence that this “linguistic divide” in SSA agriculture leads to poor understanding of science and technology (Fagerberg- Diallo, 2002). Farmer participation may require the use of local languages in order to be responsive to farmers’ needs. Despite shortcomings, a number of specific participatory approaches have the potential to improve the likely impact of AKST.