Effects of soaking seeds in exogenous vitamins on active oxygen metabolism and seedling growth under low-temperature stress

This study investigated the influence of the exogenous application of vitamin B2 (VB2), B12 (VB12), biotin (VH), and nicotinic acid (VPP) on oxygen production in maize (Zea mays L.) seedlings at 5 °C for day 1, 3, 5 and 7. The seeds were soaked in VB2, VB12, VH, and VPP solutions for 24 h at the concentration of 100 mg/L, and control was soaked in distilled water. A total of 50 seeds were used for each treatment in germination boxes was repeated three times. The germination box was placed in a hypothermic incubator for 1, 3, 5, and 7 days in the dark at 5 °C, then moved to a plant growth room and kept for seven days. Compared with the VH and VPP treatments, the VB2 and VB12 treatments had higher thiobarbituric acid reactive substances, proline, and soluble sugars. The VB2 and VB12 treatments also increased the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) than other treatments. The VB2 and VB12 treatments reduced the contents of hydrogen peroxide (H2O2–), superoxide anion (O2–), and the damage of reactive oxygen species (ROS) to cells, increased the stability of the cell membrane and the content of cell osmoregulation substances. Moreover, VB2 and VB12 had higher seedling growth, germination rate, and index. Treatments VB2 and VB12 could promote maize seed germination and growth under low-temperature stress. Exogenous vitamins in crop production can be a valuable tool for protecting plants against low-temperature stress.