Characterization of germination with physical parameters: correlation of relative mass and density as an indicator function of the germination of European Turkey oak acorn

During germination of European Turkey oak acorn (Quercus cerris L.), a linear relationship was established between mass and density. Water take-up induced by osmotic pressure of imbibition was established to be independent of the volume of the acorn. Development of the germinating acorn can be characterized by its physical parameters of relative mass (the mass of the germinating acorn divided by its mass at the beginning of germination) and density. Linear correlation between the increment of relative mass and the decrease in density reveals an important property of the germinating acorn, namely that the slopes of the straight lines fitted to the data pairs of relative mass and density can statistically be considered as a constant. On the basis of this finding, the germinating acorns having the same values of relative mass and density can be grouped into the same developmental stage.