采用 3 种方法(用 100、200、400、600 和 800 mg· L^-1 GA₃浸种 24 h、用清水浸种 6、12 和 24 h 以及用超声波处理 10、20 和 30 min)对牛皮杜鹃(Rhododendron aureum Georgi)和小叶杜鹃(R. parvifolium Admas.)种子进行预处理,以未经预处理的种子为对照,选择发芽率、发芽势和发芽指数以及萌发时滞、萌发高峰期、发芽持续时间为分析指标,对预处理后种子的萌发状况进行了比较分析。 结果表明:采用适宜的预处理方法对牛皮杜鹃和小叶杜鹃种子的萌发有促进作用;总体上看,GA₃浸种的促进作用优于另外 2 种预处理方法。 用不同质量浓度 GA₃浸种 24 h,2 种植物种子的发芽率、发芽势和发芽指数均极显著高于对照,萌发时滞和萌发高峰期均较对照缩短;其中,用400 mg· L^-1 GA₃浸种的牛皮杜鹃种子和用 600 mg· L^-1 GA₃浸种的小叶杜鹃种子的发芽率最高,分别达到 73. 50%和 81. 00% 。 用清水浸种 6 h 的牛皮杜鹃种子和用清水浸种 24 h 的小叶杜鹃种子的发芽率分别显著和极显著高于对照。 用功率 50 W、频率 40 kHz 的超声波分别处理 10 或 20 min 后,2 种植物种子的发芽率均极显著高于对照,其中,用超声波处理 20 min 的牛皮杜鹃种子和用超声波处理 10 min 的小叶杜鹃种子的发芽率最高。 清水浸种和超声波处理对 2 种植物种子的萌发时滞、萌发高峰期和发芽持续时间的影响均不明显。 研究结果显示:用 400mg· L^-1 GA3浸泡 24 h 和用 600 mg· L^-1 GA₃浸泡 24 h 分别是牛皮杜鹃和小叶杜鹃种子的最优预处理方法,可极显著提高 2 种植物种子的发芽率并缩短发芽时间。

Seeds of Rhododendron aureum Georgi and R. parvifolium Admas. were pretreated by three methods including 100, 200, 400, 600 and 800 mg· L-1 GA3 soaking for 24 h, water soaking for 6, 12 and 24 h, ultrasonic wave treating for 10, 20 and 30 min. And taking seeds without pretreatment as the control, seed germination status of two species were comparatively analyzed by means of six analysis indexes including germination rate, germination energy, germination index and delay time, peak period and lasting time of germination. The results show that suitable pretreatment methods have an effective promotion role in seed germination of two species. Generally, the promotion role of GA₃ soaking is better than that of the other methods. Germination rate, germination energy and germination index of two species seeds soaked with different concentrations of GA3 for 24 h are all extremely significant higher and delay time and peak period of germination are shorter than those of the control. In which, germination rates of R. aureum seeds soaked with 400 mg · L^-1 GA₃ and R. parvifolium seeds soaked with 600 mg· L^-1 GA₃ are the highest with percentage of 73. 50% and 81. 00% , respectively. Germination rates of R. aureum seeds soaked for 6 h with water and R. parvifolium seeds soaked for 24 h with water are significantly and extremely significantly higher than those of the control, respectively. After treated for 10 or 20 min with ultrasonic wave (50 W, 40 kHz), germination rate of two species seeds is obviously significantly higher than that of the control, in which, that of R. aureum treated for 20 min and that of R. parvifolium treated for 10 min are the highest. But effects of water soaking and ultrasonic wave treatment on delay time, peak period and lasting time of germination are not obvious. It is suggested that the best pretreatment method to R. aureum and R. parvifolium seeds is soaked for 24 h with 400 mg· L^-1 GA3 and with 600 mg· L^-1 GA₃, respectively, which can extremely significantly improve germination rate and shorten germination time.