Abstract:

The present study investigated the response of seed vigor and seedling growth of switchgrass (Panicum virgatum L.) to the artificial aging treatments. Switchgrass seeds were treated under three different artificial aging methods including accelerated aging (AA), saturated salt accelerated aging (SSAA) and controlled deterioration (CD) tests, respectively. The physiological indices including seed germination, electrical conductivity, seed imbibition and seedling growth were used for seed vigor test. Also, the pearson correlation analysis was taken to explore the relationship of different index and discuss the aging characteristics of switchgrass seeds. Results showed that germination energy, germination rate, germination index, vigor index and seed vigor were reduced gradually with the time of aging. However, the electrical conductivity of seed and the seedling biomass increased gradually. Therefore, we can believe that the main mechanism for artificial aging of switchgrass seed may be to damage the seed vigor and seed membrane permeability. And with the time of artificial aging, the damage increases gradually. The rank of the three artificial aging methods for aging effect of switchgrass seed from strong to weak was:CD >AA >SSAA.

Key words: Switchgrass, Seed vigor, Seed germination, Artificial aging, Seedling growth

摘要：

为研究柳枝稷（Panicum virgatum L.）种子活力及幼苗生长对人工老化处理的响应，分别对供试柳枝稷种子进行高温高湿老化（AA）、饱和盐溶液老化（SSAA）以及催腐劣变（CD）处理，测定不同老化处理后柳枝稷种子萌发、种子浸出液电导率、吸水率及幼苗生长等种子活力相关的部分指标，并对部分指标做了，Pearson相关性分析，以探究各指标间的关联，从而探讨柳枝稷种子的老化特性。结果表明：随着老化时间的延长，不同老化方式种子的发芽势、发芽率、发芽指数、活力指数以及活力等指标均呈现下降趋势，而浸出液电导率和幼苗生物量呈增大趋势。由此可知，老化处理降低了柳枝稷种子活力，并破坏了种子细胞膜结构的完整性，且随着处理时间延长，膜透性逐渐加剧，3种人工老化方法对柳枝稷种子的老化作用由强到弱依次是：催腐劣变老化法（CD） >高温高湿老化法（AA） >饱和盐溶液老化法（SSAA）。

关键词: 柳枝稷, 种子活力, 种子萌发, 人工老化, 幼苗生长