Abstract: In order to study the dormancy and seed germination of Leymus secalinus,seeds were soaked with 0.01~0.17 mmol·L^-1 SA,200~600 μL·L^-1 ETH and 20~60 mg·L^-1 IAA at different time intervals (12 h,24 h and 36 h),respectively. The effects of three substances on breaking seed dormancy of Leymus secalinus were studied by measuring and analyzing four seed germination characteristics,which provided theoretical basis for artificial propagation of Leymus secalinus seeds. The results showed that:suitable concentrations of SA,ETH and IAA could break the seed dormancy of Leymus secalinus effectively. After soaking with 0.05 mmol·L^-1 SA for 12 h,the highest seed germination percentage was 64%,which was twice as much as the control;when soaking seeds with 20 mg·L^-1 IAA for 24 h,the germination energy reached the maximum (i.e. 33%),which was higher than SA and ETH treatment;after soaked with 50 mg·L^-1 IAA for 36 h and 200 μL·L^-1 ETH for 12 h,seed germination percentage reached 51% and 48% respectively,which were significantly higher than the control. However,different with IAA treatment,high concentrations of SA and ETH inhibited seed germination. Therefore,0.05 mmol·L^-1 SA for 12 h had the best effect on breaking seed dormancy of Leymus secalinus.

Key words: Leymus secalinus, SA, ETH, IAA, Breaking dormancy

摘要： 为研究破除赖草（Leymus secalinus）种子休眠的方法，采用浓度为0.01~0.17 mmol·L^-1水杨酸（Salicylic acid，SA）、200~600 μL·L^-1乙烯利（Ethephon，ETH）、20~60 mg·L^-1吲哚乙酸（Indoleacetic acid，IAA）分别对赖草种子浸种处理12 h，24 h，36 h，通过测定分析4个种子发芽指标，探究这3种物质对破除赖草种子休眠的影响，为赖草种子的人工繁殖提供理论依据。结果表明：适宜浓度的SA，ETH和IAA浸种处理均能有效打破赖草种子休眠，用0.05 mmol·L^-1 SA浸种12 h后种子发芽率最高为64%，是对照的2倍；用20 mg·L^-1 IAA浸种24 h时，种子发芽势达到最大为33%，高于SA，ETH处理；其次用50 mg·L^-1 IAA浸种36 h和200 μL·L^-1 ETH浸种12 h时，种子发芽率分别为51%和48%，均显著高于对照。然而与IAA处理不同，高浓度的SA，ETH会抑制种子发芽。因此，浓度为0.05 mmol·L^-1 SA浸种处理12 h破除赖草种子休眠的效果最佳。

关键词: 赖草, 水杨酸, 乙烯利, 吲哚乙酸, 破除休眠