utilized plants, plant breeders can develop varieties of these foods that can be produced and consumed by small-scale farmers as well as sold in high value niche markets. Beyond increasing the availability of diverse foods, preservation methods must be improved to reduce the loss of micronutri-ents (Ndawula et al., 2004)
.         In addition to increasing the range of plant foods in the diet, animal source foods, such as meat, milk, and insects from wild and domesticated sources can provide critical nu­trients that may be completely unavailable in plant-based diets, such as vitamin B12 (Neumann et al., 2002; for Kenyan example see Siekmann et al., 2003). An effective strategy to increase the intake of animal source foods could include the improved small-scale livestock production through the use  of appropriate breeds,  disease prevention and con­trol,  and  affordable high  quality animal  feeds  (Brown, 2003).
        Improving soil management practices, such as increas­ing the organic matter in the soil and mineral fertilizers (Sheldrick and Lingard, 2004), can improve food security and enable farmers to produce sufficient yields and allow for more crop diversification. These practices can optimize plant nutritional quality. For example, crops grown on zinc defi­cient soils often produce grains with low zinc concentrations and these seeds may produce plants with lower grain yields and poorer seed quality (Rengel, 2001). Soil management solutions have the advantage of providing a wide range of nutrients, while other approaches, such as fortification and supplements are limited to specific nutrients.

6.7.2 Research needs for reducing malnutrition and micronutrient deficiencies
Biofortified crops developed through plant breeding can im­prove human nutrition. Biofortification has shown promise in feeding studies in the Philippines where iron biofortified rice consumption improved iron status in the study partici­pants (Murray-Kolb et al., 2004). While conventional pro­cessed food fortification can work well to improve the avail­ability of critical nutrients in the diet, rural subsistence pro­ducers may not have access to fortified foods. Thus, where food processing facilities are unavailable, biofortification can improve the availability of target nutrients. In addition, where government regulation and enforcement of food for­tification is still in the nascent stages of development, bio­fortified crops can serve as a cost-effective source of micro-nutrients. Dietary quality can be improved by selection of crop varieties that are more nutritionally dense when these are substituted for less nutritious alternatives. Consumption of carotenoid-rich red palm oil in lieu of other vegetable oils has improved vitamin A status in Burkina Faso (Zagre et al., 2003), while lysine and tryptophan-rich maize may of­fer improved growth potential for undernourished children consuming diets with low protein quality (Graham et al., 1990).
        While plant breeding efforts to biofortify staple crops are  underway,  plant-breeding programs  can  also target health-related qualities such as antioxidants in fruits or vegetables (HarvestPlus, 2006). For example, plant breed­ers can select for high lutein content, an antioxidant with beneficial effects on eye health (Seddon, 2007) in carrots

(Nicolle et al., 2004). Plant breeding can include traditional techniques and approaches using advances in biotechnol­ogy, such as rDNA. Conventional plant breeding methods have been used to develop biofortified crops and rDNA ap­proaches have increased carotenoid content in rice (Beyer et al., 2002). While approaches using rDNA and similar tech­niques have the potential to contribute to developing nutri­tionally improved crop varieties, research, monitoring, and evaluation are needed to ensure there are no adverse unin­tended consequences to human and environmental health.

Reducing food contaminants. When present in food systems, heavy metals and other contaminants, veterinary drug resi­dues, pesticide residues, pathogens, and the toxins produced by pathogens such as mycotoxins can cause a range of short-and longer-term adverse human health consequences.
        Good agricultural practices (GAPs) can lead to safer use of pesticides and veterinary drugs. GAPs can also en­able the management of risks associated with pathogen contamination of foods such as fruits and vegetables. FAO has developed guidance for governments and the private sector on conducting risk assessments and to implement­ing risk management options throughout food systems, in­cluding on-farm practices and in food processing facilities (FAO/WHO, 2006). Hazard analysis critical control point principles can be used to target issues of biosecurity, dis­ease monitoring and reporting, safety of inputs (including agricultural and veterinary chemicals), control of potential foodborne pathogens, and traceability (Olson and Slack, 2006). The development and adoption of GAPs for specific production systems and food safety/quality issues can be facilitated by approaches that involve broad participation. Plants can become susceptible to infection with the fungus that produces aflatoxins when they are exposed to water stress or insect damage (Dowd, 2003). There are readily available approaches management approaches (preharvest, harvest, and postharvest) to reduce aflatoxin (Mishra and Das, 2003); e.g., in tree nuts, peanuts, and cereals such as maize.
       In addition, dietary approaches are being developed to counteract the effects of mycotoxins (Galvano et al., 2001). Additional research is needed to verify the detoxification ability of the proposed food components, their long-term efficacy and safety, and their economic and technical fea­sibility. To manage risks associated with pathogens such as Escherichia coli O157:H7 in fruit and vegetable production, sanitation systems throughout the food production chain are integral to GAPs guidance for preventing the presence of these organisms (Fairbrother and Nadeau, 2006). Addi­tional strategies are being developed to reduce foodborne pathogens, e.g., chlorate as a food supplement to prevent colonization of food-producing animals by E. coli and other pathogens (Anderson et al., 2005).
        Achieving fuller deployment of GAPs to improve food safety  and  public   health  requires  establishing  effective national regulatory standards and liability laws that are consistent with international best practice, along with the necessary infrastructure to ensure compliance, including sanitary and phytosanitary surveillance programs for ani­mal and human health, laboratory analysis and research ca-