Effect of seed priming with zinc, iron and selenium on the low temperature tolerance of Nicotiana tabacum L. during seed germination.

Tobacco is one of the important cash crops in China. It is sensitive to low temperature, especially in the early stage of tobacco seed germination and seedling growth. Low temperature stress directly affects the germination of tobacco seeds, leading to irregular emergence and slow growth of seedlings. Therefore, it is important to improve the vigor and cold tolerance of tobacco. In this study, two cold-sensitive tobacco varieties were primed individually with ZnSO 4 , FeSO 4 and Na 2 SeO 3 to test the effects of different microelements priming on seed germination. The results showed that under low temperature (11 °C), all three elements could improve tobacco seed vigor and promote seed germination, with selenium priming exhibiting the best effect. Selenium priming significantly increased the seed vigor index of YY97 by 29.60 % and of YY85 by 47.57 %. Moreover, selenium priming could effectively enhance POD activity in seeds, promote the oxidation of phenolic substances and enhance the activities of G-6-PDH and 6-P-GDH in the process of scavenging ROS and converting H 2 O 2 to ·O 2 −. The results suggested that selenium played an important role in promoting tobacco seed germination under low temperature. • Zn, Fe and Se priming improved tobacco seed germination and seedling establishment at low temperature. • Se priming exhibited the strongest promotion effect on the anti-oxidation system. • POD activity was particularly enhanced by Se priming. • The increased POD activity promoted seed germination from multiple physiological aspects. [ABSTRACT FROM AUTHOR]