transmitting agricultural knowledge across generations. The disproportionate effect of HIV/AIDS on women intersects with their greater responsibility for agricultural production and results in decreased labor available for agriculture when women fall ill or care for others who fall ill. Also, women from AIDS-infected households are less able than others to
adopt innovations from advances in AKST. As the agricultural labor pool decreases, households retreat from cash crop production and resort to low-labor staples, often root vegetables of inadequate nutritional value. Relying on staple foods decreases household income and further stretches labor and other resources.

The effects of HIV/AIDS on agriculture are visible throughout SSA. In Uganda, for instance, AIDS-affected households in mixed agriculture, fisheries and pastoral sectors are producing less. In Zambia, AIDS-related deaths among the productive population have led to an increase in orphaned children, which places an additional burden on the community. In Uganda’s Rakai District, herd sizes have tended to decrease. Rising rates of HIV in pastoral communities are being reported in Kenya around Lake Turkana and in southern Sudan (IRIN, 2006).

Impact on agricultural extension services. Agricultural extension workers play a pivotal role in adopting and transmitting AKST. As workers spend fewer hours on the job due to illness, extension services are curtailed. A local extension officer in Uganda noted that between 20 and 50% of total work time was lost as a result of HIV/AIDS. Staff members were frequently absent from work, attending funerals and caring for sick relatives (FAO, 1994). In eastern and southern Africa, HIV and AIDS have resulted in a high number of deaths of skilled workers, whose replacement will take time (Jayne et al., 2004).

The loss of agricultural knowledge and management skills. When one or both parents die or are seriously ill, their skills may not be transferred to their children or other relatives. This may have far-reaching implications for agricultural production. In areas where the incidence of HIV and AIDS is high and agricultural skills are lacking, farming is often neglected and yields are poor.

The consequences of HIV/AIDS on rural populations and agricultural systems include the threat to household and community food security; a decline in the nutrition and health of small-scale producers and their families; a decline in educational status, as children are forced to leave school; and changes in social structures, as households adapt to the break-up of families, to the growing incidence of femaleheaded households, and to the increasing number of orphans and rural poor. The impact of the pandemic is also likely to be severest among already vulnerable populations such as those who are malnourished.

Pesticides. Health hazards from chemical pesticides are a major source of concern. After decades of extensive chemical use in many SSA countries, the long-term effects on human health and the environment cannot be oversimplified. Since 1996 several studies of large-scale agricultural enterprises in Ethiopia show that agricultural workers have health problems caused by exposure to chemical pesticides (Lakew and

Mekonnen, 1998; Mekonnen and Agonafir, 2002; Ejigu and Mekonnen, 2005). Studies of agricultural workers in Senegal (Abiola et al., 1988) and in Tanzania have reported unsafe pesticide handling (Ngowi et al., 2001). The environmental effects of these chemicals, however, have not been well studied.

3.1.2 Gender dynamics in AKST
Most women in sub-Saharan Africa bear multiple responsibilities: producing food; weeding and harvesting on men’s fields; post-harvest processing; providing fuelwood and water; and maintaining the household. The burden on rural women is increasing as population growth outpaces the evolution and adoption of agricultural technology and as growing numbers of men leave farms for urban jobs. Women’s marginalization within AKST and their overall burden and disproportionate responsibility in the household amplify their disempowerment and compromise household nutrition and food security. The vital role of women farmers requires measures to increase their managerial and technical capacity and to empower them to play a dynamic role in implementing future improvements (Dixon et al., 2001).

Women are typically marginalized at household, production and consumption levels. They are also marginalized at policy, market and institutional levels, with consequences for their households and communities. Women are usually responsible for agricultural production, but often are not empowered to make household decisions about labor and expenditures. Lower yields from farm plots controlled by women are usually the result of insufficient labor and inputs rather than poor management skills. Also, women are typically allocated land of poorer quality.

At the policy level. In some countries the state controls the land, while in others land can be owned privately. Land tenure laws, however, often favor men, sometimes even prohibiting women from owning land. This translates into a lack of collateral to obtain microfinance and credit, which could be used to hire labor, access new technologies, purchase inputs such as fertilizer and improved seed varieties, grow crops that require cash investments or buy land.

At the market level. A lack of access to microfinance and credit makes it harder for women to invest in agricultural inputs and tools that could increase yields. Typically, cash crops are seen as the province of men and it can be difficult for women to break into these markets. Access to markets, technology and practical information are keys to achieving development goals. Advances in information and communications technology, when provided to women, can be particularly effective in addressing gender issues (IAC, 2004).

At the organizational level. Women are not adequately represented among or served by agriculture extension. They represent only 3% of all agriculture extension agents in Africa (Brown et al., 1995). Women are also underrepresented in scientific research institutions, which may result in technology innovations that do not take into account women’s roles in agricultural production. For example, new crop varieties that have higher yields are often not adopted because they require inputs that women typically cannot afford, or