Abstract:

In order to study the effect of different methods on seed dormancy breaking, explore the reasons of seed dormancy and seek the best method of breaking seed dormancy, seven kinds of leguminous forages YeYe pea (Vicia tenuifolia), Sophora alopecuroides (Sophora alopecuroides), sainfoin (Onobrychis viciaefolia Scop), Rome alfalfa (Medicago falcata VAT. Romanina), Junggar rock astragalus membranaceus (Hedysarum songaricum), mountain rock astragalus membranaceus (Hedysarum shandi) and floret sainfoin (Onobrychis micrantha) seeds were used as materials, and machinery, hot water and sulfuric acid were used to break the seed dormancy, and the germination of the seedlings were counted after 15 days cultivation. The results showed that the seed dormancy of the 7 kinds of legumes all belonged to physical dormancy. Mechanical damage of skin or 5 min 80℃ hot water processing could effectively break the seed dormancy, and significantly improve the germination rate (P < 0.05), and the plant height and root length of the seedling growth for 15 ds had no significant differences compared with the blank treatment. Effect of sulfuric acid treatments varies in different species and treatment time, and the seed germination rate was increased firstly and then reduced with the extension of processing time. Overall, treatment with 98%sulfuric acid for 5 min showed the best result, the seed germination rate was significantly increased (P < 0.05). However, seedling growth had no significant differences compared with blank treatment. The results could provide a method of seed dormancy breaking for cultivation of artificial grassland and recovery of the degradation of vegetation in desert area.

Key words: Legume seed, Seed dormancy, Treatment methods, Germination, Seedling growth

摘要：

以7种豆科牧草线叶野豌豆（Vicia tenuifolia）、苦豆子（Sophora alopecuroides）、红豆草（Onobrychis viciaefolia）、罗马苜蓿（Medicago falcata）、准噶尔岩黄芪（Hedysarum songaricum）、山地岩黄芪（Hedysarum shandi）和小花红豆草（Onobrychis micrantha）的种子为材料，采用机械、热水和硫酸3种不同方法破除种子休眠，并对萌发种子所形成的幼苗进行连续15 d的培养，以期研究不同方法对种子休眠的解除效应，探讨种子休眠的原因并寻求打破种子休眠的最佳途径。结果表明：这7种豆科植物种子的休眠类型均属于物理性休眠，机械破损种皮和80℃热水处理5 min均能有效打破种子休眠、显著提高萌发率（P<0.05），且幼苗生长15 d后株高和根长与处理前相比差异均不显著。硫酸处理因物种和处理时长不同而异，且随处理时间的延长种子萌发率呈现先增加后降低的趋势。综合考虑，以98%硫酸处理5 min效果最好，此时种子萌发率显著提高（P<0.05），幼苗生长状况与处理前相比差异不显著。研究结果可为荒漠区人工草地的种植与植被退化恢复提供科学依据。

关键词: 豆科种子, 休眠解除, 处理方法, 萌发, 幼苗生长