Abstract: A field study was conducted from 2001 to 2002 in Dingxi County,Gansu Province,to analyze the seed yield and dormancy character of eight alfalfa(Medicago sativa)varieties.The results show that the seed yield of Vela is the highest,followed by Famous and Rest.The correlation between the seed yield and the yield components among the eight alfalfa varieties are similar within the two years.The statistical sequence of the correlations between the two is as follows:fertile shoots/m²>pods/fertile shoot>seeds>pod>thousand seed weight.When the viability of seeds of each of the eight alfalfa varieties are about the same,the rate of hard seed of Vela,Famous and Rest is each lower than that of the other five varieties continuously in the two years.Stored in natural conditions for a year,the viability of the seeds of the eight varieties have not changed notably,though their rates of hard seed are reduced markedly,while their rates of germination skyrocket.The rate of hard seed of Vela,Famous and Rest decreases each by 44%～56%,while their rate of germination rises to 58%～71% separately.The practical value of the seeds of the three varieties is higher than that of the other five varieties.

Key words: Grassland science, Alfalfa, Seed yield, Yield components, Dormancy character, Seed practical value

摘要： 连续2年在甘肃定西对8个紫花苜蓿品种的种子生产性能和种子休眠特性进行研究,结果表明:品种间种子产量最高的是Vela,其次是Famous和Rest;种子产量与其构成因素的相关性在年度间及品种间的表现基本一致,相关性强弱依次为生殖枝数/m²>荚果数/生殖枝>粒数/荚>千粒重;在种子生活力无显著差异情况下,Vela、Famous和Rest新收获种子的硬实率显著低于其他品种;自然条件下贮藏1年,与贮前相比种子的生活力无显著变化,硬实率显著下降,发芽率显著提高,其中Vela、Famous和Rest的硬实下降率为44%～56%,最终发芽率达58%～71%,种用价值高于其他品种。

关键词: 草原学, 紫花苜蓿, 种子产量, 产量构成因素, 休眠特性, 种用价值