**Table 6.**

*Influence of pollen heating in F1 hybrids on seed germination of BC1 offspring on osmotic in oil flax.*

placed in a thermostat and heated at 35°C for 1–2 hours. Pollen heating at a higher temperature is undesirable, since treatment at 45°C even for a short time results in a complete loss of pollen viability.

After heating, pollen was applied to the stigmas of one of the parental components of the hybrid. The fact of selection in the experiment was evaluated by the setting of seeds and capsules in comparison with pollination with freshly collected pollen. The selection efficiency was determined by the germinating BC1 seeds in an osmotic medium (**Table 6**).

As a result of pollination with heated pollen, the setting of bolls and seeds significantly (almost by 2–3 times) decreased. Even after 1 h treatment of pollen, these parameters were significantly lower than in the control.

The heating of pollen from hybrid plants influenced both the percentage of seed germination and the length of roots developed in a medium with an osmotic. At the same time, the maximum differences from the control were observed when the pollen was heated for 120 min. Thus, the selection of pollen resistant to high temperatures in *F*1 makes it possible to significantly increase the percentage of drought-resistant genotypes in the progeny of sporophytes obtained after pollination with the heated pollen. With the help of this methodological technique flax variety "Pivdenna nich" was developed which is a National Standard in Ukraine, and is perfectly adapted to the arid conditions of the south of the country.
