温度对入侵植物牛膝菊种子萌发的影响

在人工气候箱中,测定了不同温度条件下(10、15、20、25、30℃)牛膝菊种子的初始萌发时间、萌发率、日相对萌发率、发芽势、发芽指数等指标,研究不同温度对牛膝菊种子萌发的影响.结果表明:牛膝菊种子在10℃条件下未萌发.25℃是牛膝菊种子萌发最适宜温度,其发芽率为94.67%,发芽势为84%,发芽指数为22.68,均高于其他温度处理.牛膝菊种子在20℃和25℃萌发速度最快,初始萌发时间为1d,当天就达到种子萌发高峰期.较低温度(15℃)在一定程度上推迟种子的萌发高峰期,但并没有显著降低种子的最终萌发率.较高温度(30℃)不仅推迟种子萌发高峰期,而且也显著降低种子的最终萌发率.牛膝菊具有较强的繁殖特性,对种子萌发温度要求较低,在恒温条件下的适宜发芽温度范围为15~25℃.

Effects of Temperature on Seed Germination Characteristics of Galinsoga Parvi flora

The starting time of germination, germination percentage, daily relative germination rate, germination potential and germination index of Galinsoga parviflora seeds were measured respectively at 10, 15, 20, 25 and 30 ℃ in the artificial climate chamber. The results show that the seeds of G. parviflora did not burgeon at 10 ℃ ; the optimal germination temperature for G. parviflora seeds was 25℃ at constant temperature treatment, the germination percentage was 94. 67%, the germination potential was 84%, and the germination index was 22. 68. All above indices were higher than those at other temperatures. G. parviflora seeds germinated fastest at 20 and 25 ℃, the initial germination time was 1 day, and the germination rate reached at peak on the first day. The seed germination peak was delayed at low temperature （15 ℃）, but the germination rate was not significantly decreased compared with the control. The seed germination peak was also delayed at high temperature （30 ℃）, while the germination rate was significantly decreased compared with the control.