温度对入侵植物牛膝菊种子萌发的影响

Effects of Temperature on Seed Germination Characteristics of Galinsoga Parviflora

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℃．

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.