Perspectives for crop protection in sustainable agriculture

The challenge facing agriculture, particularly in developing countries, is to increase productivity without causing ecological damage. An important aspect of sustainable agriculture is the substitution of chemicals and capital with locally grown biological inputs and knowledge. Production of food grains in India has risen steadily since the 1960s, partly through the introduction of high-yielding varieties of rice and wheat together with appropriate agronomic and plant protection practices. Plant breeding programmes have improved cultivated rice by the transfer, from wild species, of genes conferring resistance to viral diseases. Diversification of resistance is sought, to render the hybrids less vulnerable to sudden outbreaks of diseases and insect pests. For wheat, resistance to rusts involves the additive interaction of several gene-encoded traits. Linkage of resistance genes with morphological markers enables the inheritance of the former to be followed easily. It is important that recent advances in molecular genetics are incorporated into integrated pest management programmes. This will require appropriate social organization. Research centres that develop and exploit genetic sources of resistance and varietal diversification should be established.