Abstract:

The paper aims to study the germination characteristics of Scoparia dulcis seeds, and provide a scientific basis for standardized cultivation of S. dulcis. The seeds of S. dulcis were used as materials under different conditions of temperature, light, gibberellins (GA) soaking, polyethylene glycol (PEG) soaking and potassium nitrate (KNO₃) soaking. The results showed that: (1) the seeds of S. dulcis did not germinate under the constant temperature of 20℃ and 35℃; the germination percentages of constant temperature of 25℃ and 30℃, alternating temperature 25℃/day and 15℃/night, 30℃/day and 20℃/night and 35℃/day and 25℃/night were 78 %, 43%, 73%, 94% and 75% respectively; (2) the seeds of S. dulcis did not germinate under full dark condition, and the seeds germinated normally after light exposure; (3) at 25℃, after soaking seeds with 1%-5% PEG-6000, 1-100 mg/L GA and 1-5 mmol/L KNO₃, the germination rates were 86%-90%, 93%-95%, and 87%-88%, respectively, significantly higher than the control treatment of distilled water. The seed of S. dulcis is light-demanding, and the suitable germination temperature is alternating temperature 30℃ at day for 12 h and 20℃ at night for 12 h, soaking seeds in PEG-6000 (1%-5%), GA (1-100 mg/L), and KNO₃ (0.01-5 mg/L) solution can promote the germination of S. dulcis seeds.

Key words: Scoparia dulcis, seed germination, temperature, light, regulator