Improved Equations for the Prediction of Seed Longevity

Equations for predicting seed longevity in storage have been improved so that they now take into account variations within a species in initial seed quality—which is affected by genotype and pre-storage environment—and so that they are more accurate over a wider range of storage environments These improvements have been incorporated into a seed viability nomograph for barley (Hordeum distichum L.) which may be used to predict percentage viabihty of any seed lot after any time in any storage environment within the range −20 to 90 °C and 5–25 per cent moisture content. Applications of the improved equations to seed drying and to long-term seed storage for genetic conservation are discussed.