Temperature

We can also predict survival curves for seeds stored at different temperatures. Figure 8 (below) shows the effect of storing chickpea seeds at 6% moisture content in medium-term storage (5°C) and in long-term storage (-20°C). Over a period of 280 years, you can see the survival of the seeds in medium-term storage starting to tail off. For seeds in long-term storage, it looks like they’re barely losing viability at all, but they are – just very slowly!

The graph shows the impact of temperature on seed longevity.  The x axis is passage of time. The y axis is the percentage of seeds that will germinate after removal from storage. Two graphs are plotted, corresponding to five degrees Celsius and minus twenty degrees Celsius.  At five degrees Celsius, the viability curves off perceptibly, reaching eighty five percent after about a century. At minus twenty degrees, the reduction in viability is barely detectable, although you can see a very slow decline over a timescale of two hundred and eighty years. 
Figure 8: survival of seeds at different temperatures

The fact that there are there are differences in survival as a result of temperature means that it is important, when recording seed viability in storage, that you specify the temperature at which the seeds were stored, as well as their moisture content.

Moisture content

Dormancy