The effect of abscisic acid and cytokinins on the cold hardiness of winter wheat

Abstract

The effect of abscisic acid (ABA) and the cytokinins benzyladenine (BA) and kinetin on the cold hardiness of winter wheat (Triticum aestivum L.) was investigated by controlled freeze tests. ABA or BA applied as a foliar spray to nonacclimated plants or to plants acclimated for 1 week had no measurable effect on crown cold hardiness. The crown water content of winter wheat plants grown in nutrient solution supplemented with BA or kinetin decreased by twofold but cold hardiness was not increased. Thus, a reduction in water content alone does not necessarily result in increased cold hardiness. After 7 days of hardening ABA added with BA increased cold hardiness of crowns 3 to 4 °C depending upon the treatment.