Five winter wheat: Alcedo, Beta, Grana, Liwilla and Salwa in four levels of moisture: 5, 9, 16 and 21 % were examined. Grains came from 1984, 1985 and 1986. Static compression test of a single grain was performed between two parallel plates. Maxial compression force and deformation corresponded to it as well as force and deformation within limits of elasticity were read from the curves in force - deformation coordinate system. Point where curve bent was regard as a limit of elasticity (first failure). Alcedo was the most resistible, while Salwa was the weakest variety. Grains came from 1984 were the strongest and from 1985 were the weakest. Moisture content was the most substantial factor to the strength of wheat grains. With the increase of moisture content maxial compression force decreased, while corresponded deformation increased.
The paper presents the results of research on the mechanical properties of seven potato varieties in three different phases of the storing period. The effect of the date of damage on the stroing losses is analyzed. The correlation between the actual storage damage (the simulation drum of damage) and some of the mechanical resistance parameters is also examined.