“吸湿-回干”处理对砂生槐种子萌发的影响

Effects of hydration-dehydration treatment on seed germination characteristics of Sophora moorcroftiana

砂生槐(Sophora moorcroftiana)是西藏特有沙生药用植物,在极其恶劣的自然生态环境下,种群的自然更新受到诸多非生物逆境的影响,比如干旱或降雨不稳定等因素的影响,土壤中的种子经常由于吸收的水分不足又出现回干的现象,反复经历"吸湿-回干"的过程.本文研究了砂生槐种子的吸水率、不同吸湿时间和不同"吸湿-回干"处理次数对砂生槐种子萌发情况的影响.结果表明,只要打破种皮的限制,砂生槐种子在极短的时间里即能达到饱和,吸水率最高达367.03%;并且"吸湿-回干"处理能够明显的促进砂生槐种子的萌发,种子的发芽势、发芽指数均有显著的提高(P<0.05),但是对砂生槐种子发芽率的影响并不明显;其中以经历1次"吸湿-回干"处理且浸种6 h的处理效果最好,砂生槐种子萌发的各项指标最高,发芽势、发芽率、发芽指数分别为60.67%、91.33%、22.65,均高于对照.

Sophora moorcroftiana is a kind of particular desert medicinal plant in Xizang. In extremely harsh natural environment,natural regeneration of population was affected by many abiotic stresses, such as drought or instability in the rainfall. As a result of lack water, seeds in soil often experience dehydration. After raining, seeds would go through ＂hydration-dehydration＂ process.Therefore, this paper maily studies the water absorption rate of Sophora moorcroftiana seed, and the effect of different absorbent time and different ＂hydration-dehydration＂ process times on Sophora moorcroftiana seed germination. The results show that Sophora moorcroftiana seed can reach saturation in a very short period of time, as long as the broken seed coats, the water absorption rate up to 367.03%; ＂hydration-dehydration＂ process can significantly promote seed germination of Sophora moorcroftiana. And germination energy and germination index showed a significant increase（P0.05）, but impact on germination rate is not significant. In all treatments, seed soaking 6 h and ＂hydration-dehydration＂ process once is the best. In this treatment, Sophora moorcroftiana＇s seed germination energy, germination rate, germination index were 60.67%, 91.33%, 22.65 respectively, they are higher than those of the control.