The changes in the seeds germination capacity of the hexaploid wheat variety Odesskaya 267 after different periods of immersion in water at a temperature of 4 C were studied. The seeds immersion in water for up to 104 hours was accompanied by rapid absorption of water in the first 32 hours (phase I), followed by a slow increase in seed moisture over the next 72 hours (phase II). The seeds sensitivity to the application of heat shock (4852 C) increased with the immersion time, which, together with the improvement of their germination parameters during phase I and the first part of phase II, suggests the seeds coming out of dormancy and initiating processes of germination. The sensitivity to heat shock of the seminal roots initials, especially of the radicle, gradually increased with the imbibition time expansion. Their meristems initials cells have progressed more in exit from dormancy and germination processes intensification during this period. The elaborated method of assessing the seed resistance to heat shock is prospective to compare the primary resistance (without the involvement of adaptation processes) of different wheat genotypes to high temperatures.

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The primary resistance and plasticity of the response to shock with negative temperatures (SNT) or heat shock (HS) of different winter wheat genotypes grown in Ukraine and then reproduced in Moldo-va are determined. The values of the mentioned parameters specifically varied depended on the genotype specificity and conditions of seeds reproduction. Thus, data support the hypothesis about the specificity of trans-generational inheritance of wheat genotypes adaptations to extreme temperatures. Furthermore, the correlation coefficient between the resistance SNT value to HS and inversed value (HS/SNT) ratio may indicate the epigenetically inherited effects.

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