外来入侵植物三叶鬼针草种子萌发与贮藏特性研究

Studies on Seed Germination and Storage of the Invasive Alien Species Bidens pilosa L.

研究了光照和温度对外来入侵植物三叶鬼针草(BidenspilosaL.)种子萌发的影响及种子在不同温度下贮藏后的发芽力变化。结果表明,光照和变温不是三叶鬼针草种子萌发的必要条件,在15～30℃恒温条件下萌发率均达到80%以上,35℃恒温显著抑制其萌发且发芽的种子不能正常发育;零下低温(-10℃)和零上低温(4℃)贮藏6个月的三叶鬼针草种子萌发率(分别为95%和94.7%)与贮藏前的萌发率(97.7%)相比无显著差异,而在室温下贮藏6个月的种子,随着贮藏时间的增加萌发率逐渐下降,6个月后不仅萌发率急剧下降到16%、萌发时间延长至10d,而且发芽的种子亦不能正常发育。

Bidens pilosa L. is an invasive alien weed. The effects of temperature and illumination on seed germination of B. pilosa and changes of germination capacity during its storage under different temperature were studied. The results showed that illumination and natural temperature fluctuations are not necessary for its seed germination. Under the conditions of constant temperature from 15 to 30℃, the germination percentages reached above 80%, but under constant 35℃, seed germination was greatly restrained to a very low level and the seeds germinated could not complete their development into seedlings as well. There was nearly no difference in germination percentage between fresh seeds (97.7%) and seeds stored at -10℃ and 4℃ for 6 months (their germination percentages were 95% and 94.7%, respectively). As for the seeds stored at room temperature for 6 months, the germination rate decreased gradually and the sprouted seeds could not develop normally.