摘要
陕西羽叶报春(Primula filchnerae)是百年绝迹、曾被植物界视为可能绝灭的二年生草本植物,其种子萌发和成苗是其种群续存的前提,也是其园林开发时繁育工作的理论依据。本研究发现,陕西羽叶报春种子细小,25℃、低光(2700 lx)和当年采集种子是其萌发的最适条件。然而,该条件的成苗率仅25%左右,成苗/萌发比也比其它处理低。29℃高温下陕西羽叶报春种子存在一定程度的休眠,赤霉素(GA3)处理后萌发率虽显著增加,始萌发时间缩短,但高浓度(200 mg/L)GA3处理使种子成苗率和成苗/萌发比显著降低。经过2个多月的高温高湿(29℃下萌发)处理后,将未萌发的种子重新在最适温度25℃下萌发,发现它们的萌发率不受影响,但始萌发时间显著缩短。以上结果说明陕西羽叶报春种子成熟后,及时采收并适当让其高温休眠一段时间,萌发时先用低浓度(20 mg/L)GA3处理,不但可以显著提高萌发率,而且可提高成苗率和成苗/萌发比。
Primula filchnerae,which disappeared more than one hundred years ago and was assumed extinct,was rediscovered in 2006 in Zhuxi and Zhushan County, Hubei Province,China. Studies on seed germination and seedling formation of P. filchnerae will contribute to the protection of the species and its landscape development. Seeds of P. filchnerae were small and the thousand seed weight was 0.90 ＋0.12 g. We determined 25℃,2700 Ix and fresh seeds as the optimum condition for seed germination, The seedling rate, however, was only about 25% and the seedling germination ratio was significantly lower than other conditions. Seed dormancy occurred at 29℃; however 200 mg/L gibberellins （ GA3） treatment significantly increased the germination rate, decreased the time to start germination, seedling rate and seedling germination ratio. After more than two months of high temperature and high humidity （29℃ germination condition） treatment,the germination rate of all un-germinated seeds remained unchanged but the time to start germination decreased significantly when they were transferred to 25℃. These results showed that dormancy at high temperature followed by soaking with 20 mg/L GA3 before seed germination, significantly increased the germination rate, seedling rate and seedlina aermination ratio of P. filchnerae.
出处
《植物科学学报》
CAS
CSCD
北大核心
2011年第2期212-217,共6页
Plant Science Journal
基金
湖北省自然科学基金项目(2009CDB030)
关键词
陕西羽叶报春
种子萌发
成苗率
极危植物
休眠
Primula filchnerae
Seed germination
Seedling rate
Critically endangered plant
Dormancy
