初生休眠解除状态和干燥处理对水曲柳种子萌发的影响

为探究初生休眠解除状态和干燥处理对水曲柳种子萌发的影响,本文以初生休眠的成熟水曲柳种子为材料,研究经不同裸层积(暖温10周+低温8周、暖温12周+低温8周、暖温10周+低温10周、暖温12周+低温10周)和干燥处理(干燥、不干燥)的水曲柳种子在适宜温度和较高温条件下的萌发表现。结果表明,初生休眠解除状态不同的水曲柳种子在不同温度下的萌发表现具有相似的规律,种子的萌发会受到干燥处理的影响。不经干燥处理的种子解除休眠越充分,其萌发能力就越强,但层积处理后的种子若经过干燥处理,则解除休眠越充分(尤其是低温时间越长),种子萌发能力下降越多。水曲柳种子次生休眠(热休眠)的诱导受种子初生休眠解除状态的影响较小,但受干燥处理影响较大。干燥处理会降低水曲柳种子的萌发能力,尤其是较高温条件下的萌发能力,初生休眠解除越充分的种子萌发受干燥处理影响越大。生产中如需对解除休眠的种子干燥处理,选择暖温10周+低温8周的层积方法处理种子效果最好。

Effects of Primary Dormancy-released Status and Drying Treatment on Germination of Fraxinus mandshurica Seeds

In order to explore the effects of different primary dormancy-released status and drying treatment on the germination of Fraxinus mandshurica seeds, we used mature F.mandshurica seeds with primary dormancy to study different naked stratification(warm stratification for 10 weeks and cold stratification for 8 weeks, warm stratification for 12 weeks and cold stratification for 8 weeks, warm stratification for 10 weeks and cold stratification for 10 weeks, warm stratification for 12 weeks and cold stratification for 10 weeks) and drying treatment(drying or not drying) of F.mandshurica seed germination performance under suitable temperature and higher temperature conditions. The results showed that the germination of F.mandshurica seeds with different primary dormancy-released status was similar at different temperatures, and the germination of the seeds was affected by drying treatment. The more fully the seeds without drying breaking the primary dormancy were, the stronger their germination ability was. However, if the dormancy-released seeds were subjected to the drying treatment, the more dormancy was released(especially the longer low temperature time), the more the seed germination ability decreased. The induction of secondary dormancy(hot dormancy) of F.mandshurica seeds was less affected by the state of seed primary dormancy breaking, but was more affected by the drying treatment. Drying treatment can reduce the germination ability of F.mandshurica seeds, especially under higher temperature conditions, and the more fully breaking the primary dormancy, the greater the impact of drying treatment on seed germination. In the production, if the dormancy-released seeds need to be re-dried, the best method of stratification is warm stratification for 10 weeks and cold stratification for 8 weeks.