The saturated salt accelerated aging test for small-seeded crops

The accelerated aging test is an important seed vigor test for many large-seeded crops, but its value in small-seeded crops has been limited because moisture uptake is too rapid resulting in fast seed deterioration for some species. This study examined a method to retard small seed moisture uptake in an accelerated aging test. High and low quality impatiens (Impatiens wallerana Hook) seed lots were exposed to three different saturated salt solutions producing differing relative humidities (KCI-87%, NaCI-76%, and NaBr-55% RH) at 38 and 41 °C. All other equipment and procedures were the same as recommended for a standard accelerated aging test. As relative humidity of the accelerated aging chamber declined, seed moisture content decreased. Seed deterioration of the small-seeded crop increased with increasing relative humidity so that useful accelerated aging results that correlated with seed vigor could be obtained with either KCI or NaCl after 4 days germination by aging for 72 h and 96 h at 38°C for KCl and NaCl, respectively, or 48 h at 41°C for both salts. These results demonstrate that saturated salt solutions modify the relative humidity of an accelerated aging test making use of this valuable seed vigor test applicable to impatiens and likely other small-seeded crops.