RESUMO
It was shown for the first time that the treatment of winter wheat (Triticum aestivum L.) seeds with gold nanoparticles (average diameter 15.3 nm; solution concentration 20 µg/mL) increases plant tolerance to low temperature. It was found that an increase in tolerance under the influence of nanoparticles is accompanied by a number of changes depending on temperature conditions. In optimal temperature conditions, gold nanoparticles stimulated plant growth and the activity of the photosynthetic apparatus, whereas in conditions of low-temperature hardening (2°C, 7 days) they inhibited growth but maintained photosynthetic activity, contributing to the accumulation of soluble sugars (cryoprotectants) in the leaves. It is concluded that gold nanoparticles can be considered as adaptogens that increase plant tolerance to low temperatures; however, their effectiveness in this role and the subtle mechanisms of action require further study.