Cuba's agriculture after the 1959 revolution had been based on large-scale, capital intensive monoculture, which made Cuba heavily dependent on the socialist bloc for subsidized agrichemical inputs and for set prices of agricultural exports. However, with the collapse of the Soviet Union and its Eastern European allies in 1989–90, Cuba's inputs of fertilizer, pesticides, and petroleum dropped by more than half Cuba responded with a dramatic shift in its agricultural development model that featured appropriate technology, alternative organization of labor, alternative planning, and environmental preservation. Cuban pest control efforts now focus on biological control and on enhanced monitoring and diagnostic techniques. Soil management emphasizes biofertilizers and vermiculture. Minimum tillage and crop rotation are frequent practices among Cuba's independent farmers, agricultural cooperatives, and state farms. The transition to low-input agriculture has decreased the exodus of people from rural areas to cities, and has lead to establishment of lab or camps with volunteer labor and long-term programs for rebuilding rural communities. To address the loss of important food imports while ensuring environmental conservation, agricultural planning now gives priority to crop rotations, city gardens, and introduction of food crops in sugar cane areas.

What scientists include among the essential attributes of sustainable agricultural systems can influence the development of agricultural research agendas and how research is done. Current perspectives on sustainability place varying emphasis on environmental and agrarian values and propose different amounts and kinds of change in agricultural production, agricultural science, and rural social institutions. In a delphi study, agricultural scientists at North Central region land-grant universities considered environmental management and development of new farming technologies as essential to a definition of sustainable agriculture, but gave little importance to social or scientific restructuring. With some qualifications, we characterize their view of sustainability as a stewardship perspective that does not include social considerations and explicitly rejects radical social change.

Amaranth is an alternative grain crop that shows significant promise in the U.S. A geographic information system (GIS) was used to analyze the most suitable regions for growing amaranth in Missouri. GIS software provides tools to manipulate and display geographically based information, in this case the factors affecting amaranth's suitability. Of several such factors considered, the ones used were soils, rainfall, sorghum production, disease potential, and labor availability. Soil, rainfall, and disease information were assumed to be direct factors in yield potential. Current sorghum production areas were considered likely areas for amaranth production, given the similarities between the crops. Labor availability also was assumed to affect adoption, since amaranth requires more labor than traditional grain crops. The analysis showed that central and southeastern Missouri would be the most favorable areas for amaranth production. Other suitable areas are along the Mississippi and Missouri river valleys and in western Missouri. This GIS approach can be modified to include additional factors and refinements, and could be used with other alternative crops or for other regions of the country.

We evaluated selected cool-season annual and perennial legumes as potential ground covers to supply nitrogen and to increase beneficial arthropod populations in a pecan orchard. Densities of aphids (Homoptera: Aphididae), lady beetles (Coleoptera: Coccinellidae), damsel bug (Hemiptera: Nabidae), green lacewings (Neuroptera: Chrysopidae), brown lacewings (Neuroptera: Hemerobiidae), hover flies (Diptera: Syrphidae), spined soldier bug and other stink bugs (Hemiptera: Pentatomidae), and spiders (Araneida) were monitored at 7–14 day intervals during the growing season for three years. Aboveground biomass production and nitrogen content of the legumes was measured for two years. Aphids peaked during early spring each year, with the highest density usually on ‘Dixie’ crimson clover and ‘Kenland’ red clover. Density of lady beetles was positively correlated with that of aphids, but spider densities were not. Other arthropods usually were not abundant. Nitrogen in the tops of the annual legumes ranged from 20 kg/ha to 89 kg/ha when assessed after a single harvest at anthesis; for the perennial legumes it was from 108 kg/ha to 179 kg/ha following two harvests in June and September. We chose two annual legumes (‘Dixie’ crimson clover and hairy vetch) and two perennial legumes (‘Louisiana S-1’ white clover and ‘Kenland’ red clover) for further evaluation.

Participatory assistance (PA) is a proposed approach for promoting change that involves both the biophysical processes of farms and the management processes of farmers. It integrates external expertise, inputs, and expectations with the unique character of a particular farming system. It focuses on improving the processes of the farm and farmer rather than on the traditional interests of “outsiders” such as disciplinary researchers, industry sales people, government regulators, consumers, or environmental interest groups. As an alternative to transfer of technology, it promotes learning both by the farmer and by specialists from academia, industry, government, and the public. Participatory assistance can promote innovations in the operation of farms, in the conduct of research and education, in the development of products and services, in the formulation of policy, and in the involvement of the public in agriculture. The outcome is not assumed to be the adoption of the “best” technology, but may be found in the emerging properties that result from innovations. Assessing the improvement that follows each innovation will require clear specification of the relevant performance criteria, provision of appropriate technical support, and reinforcement by the appropriate incentives. Reconciling today's farming with water quality protection illustrates the potential of the PA approach.