Abstract: In this experiment, the seeds of Kentucky bluegrass 'Midnight' which had been stored for 5 years were used as materials. The seeds were primed by KNO₃ or ascorbic acid at different concentrations for 0, 1 or 2 d, respectively, then dehydrated for 8 h. The germination percentage, vigor index, mean germination time, shoot length, shoot fresh weight, root length and root fresh weight were determined to explore the effects of KNO₃ and ascorbic acid priming on the vigor of aged Poa pratensis seeds. The results were as follows. The germination percentage, vigor index, root length, shoot length and root fresh weight of aged seeds under KNO₃ or ascorbic acid treatment were significantly higher than those of the control, and the mean germination time was significantly shortened, but the effect on shoot fresh weight was not significant. With the membership function analysis, 0.5 mmol·L^-1ascorbic acid priming for 2 d was considered as the best treatment, resulting in that the germination percentage and vigor index were elevated by 25.24% and 41.54%, respectively, and the mean germination time was shortened by 1.76 d, compared with the control.

Key words: Poa pratensis, Aged seeds, Priming treatment

摘要： 试验以贮藏5年自然老化的草地早熟禾(Poa pratensis)'午夜’种子为材料，采用不同浓度的KNO₃(0%，1.0%，2.0%和4.0%)和抗坏血酸(0，0.5，1.0和1.5 mmol·L^-1)引发0，1和2 d后，回干进行发芽试验，测定发芽率、活力指数、平均发芽天数、芽长、芽鲜重、根长和根鲜重等指标，探究其对草地早熟禾老化种子活力的影响。结果表明：各浓度梯度KNO₃和抗坏血酸处理后，草地早熟禾老化种子的发芽率、活力指数、根长、芽长和根鲜重均较未引发处理显著提高，平均发芽天数显著缩短，对芽鲜重的影响不显著；通过隶属函数分析得出，0.5 mmol·L^-1抗坏血酸引发2 d缓解老化效果最佳，发芽率和活力指数分别比对照提高25.24%和41.54%，平均发芽天数比对照缩短1.76 d。

关键词: 草地早熟禾, 种子老化, 引发处理