不同温度处理对橡胶草种子发芽特性的影响

Effects of Different Temperature Treatments on Seed Germination Characteristics of Taraxacum kok-saghyz Rodin

为明确橡胶草人工育苗合理播种期和播种技术,设置了不同温度梯度和冷热预处理,研究了其对橡胶草种子发芽率、发芽势、发芽指数及活力指数的影响。结果表明：不同温度对橡胶草种子的发芽率、发芽势、发芽指数及活力指数的影响显著,在5-35℃范围内,随温度的上升呈先增后减趋势,其中25℃时种子发芽率、发芽势、发芽指数及活力指数均达到最大值,分别为85%、79%、14.17及33.87,而且该温度下种子发芽所需时间较短,发芽速度最快;冷热预处理对橡胶草种子发芽率影响不显著,而对活力指数的影响显著,5℃处理8-20天或35℃处理6-18 h的种子活力指数显著高于对照。因此,橡胶草种子发芽最适温度为25℃,5℃处理8-20天或35℃处理6-18h有利于提高种子发芽特性。

The study was carried out to explore the reasonableseeding time and techniques of Taraxacum kok- saghyz Rodin artificial breeding. Effects of temperature and cool or warm pretreatment on the germination of Taraxacum kok-saghyz Rodin seeds were studied by observing their germination characteristics such as germination rate, germination potential, germination index, and vigor index. The results showed that different temperatures significantly influenced germination characteristics mentioned above, which firstly increased and then decreased as temperature increased in the range of 5 to 35℃. Under the condition of 25℃, the germination rate, germination potential, germination index, and vigor index of seeds achieved the maximum value, 85%, 79%, 14.17 and 33.87 respectively, and the germination time was shorter and the germination rate the fastest. Besides, the vigor index of seeds was significantly influenced but germination rate was not by the cool or warm pretreatment. Seeds with pretreatment of 8 to 20 days at 5℃, or 6 to 18 hours at 35℃ got higher vigor index than that of the control. Thus, the optimum germination temperature for seeds was 25℃, and pretreatment of 8 to 20 days at 5℃, or 6 to 18 hours at 35℃ could improve the germination characteristic.