Management of Seed-Borne Diseases: An Integrated Approach

Productivity and sustainability in agriculture can be achieved either by increasing crop production through the use of high-yielding crop varieties or by avoiding crop failures mainly due to pests and diseases. High-yielding cultivars are often susceptible to one or more diseases. The basic need therefore is availability of good quality healthy seed/planting materials. Seeds are known to be carriers of a large number of microorganisms. Since about 90% of the crops are grown through seeds, they are also a potent source for dissemination of various diseases and survival of pathogens from season to season. Healthy seed can be obtained through appropriate certification schemes or by effective seed treatments, but it is difficult to restrict seed-transmitted diseases, which are also soil-borne, or perpetuate on plant residues. In order to reduce yield losses caused by diseases, farmers adopt calendar-based chemical spraying schedules rather than need-based sprayings, which lead to chemical residues in the produce and development of resistance in the pathogens and disturb the natural fauna. Losses due to plant diseases are expected to have more critical influence on human being in the coming years than they have had in bygone years. An integrated approach is needed for the effective control of the diseases and production and maintenance of pathogen-free seed in the field and during storage.