Implications of new technologies for seed health testing and the worldwide movement of seed

New techniques for the accurate and feasible detection of many seedborne pathogens have been developed over the last 25 years. These include conducive environmental incubation and identification (many seedborne fungi), liquid plating assay (seedborne bacteria), enzyme-linked immunosorbent assay (seedborne viruses) and polymerase chain reaction (PCR) technology. Regardless of the detection methodology, the specificity, sensitivity, reliability, efficiency of the assay and an understanding of pathogen tolerance in a seedlot need to be considered before a technique is an acceptable clinical seed health test. Acceptable seed health tests are tools for disease risk-management and routinely used in seed quality assessment. Seed health issues are increasingly important in international seed trade. With the advent of free trade, many countries are redefining their phytosanitary requirements with the goal of preventing introduction of a devastating pathogen into their country. However, many phytosanitary regulations are implemented without fully understanding the economic threat of a pathogen or a complete scientific analysis of a pathogen's presence in that country. This has led to confusing regulations, unnecessary tests or inspection requirements and unjustified trade barriers. To provide a means to answer scientifically the problems encountered in the worldwide movement of seed, an international movement has emerged to standardize seed health tests and inspection practices for international seed trade. The impact of standardization on the free trade of seed and the goals of the International Seed Health Initiative (ISHI) will be discussed. for most phytosanitary certification.