Abstract
It was found that the water in seeds could be measured as bound and free water, and it was quantitated here by the TDR method.
When radish seeds were dried for 24 hours at 25°C, the water in the seeds suddenly decreased, and when the seeds were dried for 10 hours, the free water decreased more than the bound water, and germination was hardly affected. However if the seeds were dried for over 24 hours, theamount of bound water decreased more than the free water.
In this case, germination of seeds suddenly decreased. Germination was 20%, when the seeds were dried for 96 hours at 45°C, and it was 50% at 25°C.
Therefore both bound and free water are needed for germination, and it is the quantity of bound water which affects the germination of seeds, this can be called the vital water.
