论文部分内容阅读
以沙生木地肤种子为材料,置于不同变温,不同NaCl和PEG-6000浓度下进行萌发试验,探讨温度、盐胁迫和干旱胁迫对其发芽率和幼苗生长的影响。结果表明:沙生木地肤种子萌发的适宜温度为25℃/15℃,发芽率为(92±3.27)%,但与20℃/10℃和15℃/5℃下发芽率无显著差异,过高温或过低温周期对种子的萌发和幼苗生长具有抑制作用。低浓度的NaCl溶液(≤0.2mol/L)对种子的初始发芽率和最终发芽率没有显著影响,随着NaCl浓度的增加,种子的发芽率和幼苗生长高度整体呈下降趋势,种子的初始发芽时间逐渐推后,NaCl浓度>1.0mol/L,种子仍能萌发,但幼苗生长基本停止;PEG胁迫下,沙生木地肤种子表现出较好的抗旱性,渗透势≥-1.0MPa下,PEG胁迫对种子的萌发抑制作用不明显,渗透势降低到-1.6MPa时,发芽率仍高于40%,萌发幼苗仍能缓慢生长。
The seed of Saxinka tomentosa was used as the material, and germinated under different temperature and different NaCl and PEG-6000 concentrations to study the effects of temperature, salt stress and drought stress on its germination rate and seedling growth. The results showed that the suitable germination temperature was 25 ℃ / 15 ℃ and the germination rate was (92 ± 3.27)%, but there was no significant difference with the germination rate at 20 ℃ / 10 ℃ and 15 ℃ / 5 ℃, Excessively high or low temperature cycles have inhibitory effects on seed germination and seedling growth. Low concentration of NaCl solution (≤0.2mol / L) had no significant effect on the initial germination rate and final germination rate of the seeds. With the increase of NaCl concentration, the seed germination rate and seedling growth height decreased overall, and the seed germination Under the condition of NaCl concentration> 1.0mol / L, the seeds could still germinate, but the growth of seedlings basically stopped. Under the PEG stress, the seeds of A. koraiensis seedlings showed better drought resistance, osmotic potential ≥ 1.0MPa, Under PEG stress, the seed germination was not obvious. When the osmotic potential decreased to -1.6MPa, the germination rate was still higher than 40%, and germination seedlings could still grow slowly.