多巴胺引发对盐胁迫下水稻种子萌发及幼苗生长的影响

目的]探讨多巴胺(Dopamine,DA)引发对盐胁迫下水稻种子萌发及幼苗生长的影响.方法]以新疆自育水稻品种新稻17号为研究对象,分别用0(纯水)、0.1、0.5、1、1.5 mg/L的DA溶液(分别用S0、S0.1、S0.5、S1、S1.5表示)引发种子,采用浓度为100 mmol/L的NaCl溶液模拟盐胁迫,...

Effects of Dopamine Priming on Seed Germination and Seedling Growth of Rice Under Salt Stress

【Objective】 It is of significance to clarify the effects of dopamine priming on rice seed germination and seedling growth under salt stress. 【Method】 The effects of seed priming on seed germination, seedling growth and physiological characteristics under salt stress were analyzed. Rice (Variety: Xindao 17) seeds were primed with 0（H₂O）, 0.1, 0.5, 1 and 1.5 mg/L dopamine solution, respectively. Salt stress was simulated with 100 mmol/L NaCl solution. The no-priming and no-salt stress treatment was kept as control 1(CK), and the no-priming with salt stress was kept as control 2(S-CK). 【Result】 Compared with CK, salt stress (S-CK) obviously slowed down or stopped the germination of rice seeds, and the rice seedlings grew weakly. The priming treatment relieved the inhibitory effect of salt stress on rice seeds germination, speeded up the germination (13.3%–25.8%), promoted seedling growth, increased the contents of soluble sugar(16.4%–51.8%), proline(6.5%–31.2%), and enhanced the activities of SOD(28.9%–72.7%), POD(15.0%–60.1%) and CAT(35.1%–133.0%), decreased the content of MDA(7.1%–26.8%). The results indicated that seed priming could enhance salt tolerance of rice seeds and seedlings by improving the vigor of rice seeds, the activities of antioxidant enzymes and the contents of osmotic regulatory substances, and decreasing the content of MDA. The medium concentration of dopamine solution (S1) was better than water(S0). 【Conclusion】 The suitable priming solution for Xindao 17 was 1.0 mg/L dopamine, which could effectively enhance salt tolerance of rice seeds, and promote seed germination and seedling growth.