Abstract:

The storage aging of maize seeds can easily lead to the decrease of germination activity and uneven emergence. Therefore, new green and efficient seed priming technologies are urgently needed in production. β-Ocimene is an important plant signal volatile substance, but its effect as a seed initiator is not yet clear. In order to explore the regulatory effect of β-ocimene on maize seed germination, taking maize seeds as the experimental materials, five concentration levels of β-ocimene treatment groups (0, 0.5, 1, 1.5, and 2 mmol/L) and three treatment durations (6, 12, and 18 h) were set. The germination rate, germination index, vigor index, seedling root length, seedling height and biomass were measured by completely random design, and the optimal priming combination was screened by membership function method and correlation analysis. The experimental results showed that β-ocimene priming for maize seed germination was significantly better than that of the distilled water control priming group. According to the analysis of time and concentration gradients by the subordinate function method, the 18 h treatment was the best, followed by 12 h, and the 6 h treatment had the worst effect. Among all treatments, the combined treatment of 1.5 mmol/L β-ocimene priming for 18 h had the best effect. Under this combination, the seed germination index was the highest (30.38), the vigor index was the highest (1173.92), the seedling root length was the longest (24.08 cm), the seedling height was the highest (15.32 cm), the fresh weight was the highest (1.53 g), and the dry weight was the highest (0.15 g). This experiment is the first to find that pre-soaking treatment with β-ocimene can significantly improve the germination rate and vigor of maize seeds. The results of this study provide a new priming agent for maize seed priming, and also provide a useful reference for seed priming of other crops.

Key words: maize seeds, β-ocimene, seed priming, seed priming agent, seed germination, pre-soaking treatment, seed priming technology, seed germination parameters