变温层积过程中圆齿野鸦椿种胚形态及生理生化变化

Changes in Embryo Morphology,Physiology and Biochemistry of Euscaphis konishii Seeds in Variable Temperature Stratification

圆齿野鸦椿种子经50%浓硫酸和200 mg/L的GA3浸泡后,再进行变温(即4℃90 d,25℃90 d,4℃90 d)层积处理。分别于变温层积前和变温层积过程中(每隔90 d)定期取样观察种胚形态、淀粉、可溶性糖、可溶性蛋白、粗脂肪含量以及淀粉酶和过氧化氢酶活性的变化。结果表明,种子采收后胚尚未分化完全,种胚形态在变温层积过程中逐渐分化发育完全。另外,在变温层积过程中,可溶性糖和可溶性蛋白的含量先升后降,再升,总体呈升高趋势;淀粉含量呈下降趋势;脂肪含量也表现为逐渐下降且低温层积较暖温层积阶段下降更明显;淀粉酶活性的变化趋势与淀粉含量的变化趋势相反,在层积过程中呈上升趋势;过氧化物酶的活性在变温层积过程中的各个阶段均表现为极显著地上升。由此可见,低温层积较暖温层积更有利于打破圆齿野鸦椿种子的生理休眠,种子生理生化变化与种胚形态后熟呈现高度的一致性。

In this study the seeds of Euscaphis konishii were selected as the trial material .First, soaked they were soaked in sulfuric acid of 50%concentration for 10 minutes;second ,soaked in GA 3 of 200 mg/L for 24 hours;lastly treated with temperature-accelerated stratification （4℃ 90 days,25 ℃ 90 days,4 ℃ 90 days）.By periodical sampling.The changes in embryo morphology;the changes in content of amylum ,soluble sugar ,soluble protein and rough fat and the changes in the activity of amylase and peroxidase were observed and recorded .The results showed that the embryo differention of Euscaphis konishii seeds completed .During the temperature-accelerated stratification , the differentiation and development of embryo matured gradually , the contents of soluble sugar and protein rose at first ,then decreased ,rose again .On the whole ,it showed a trend of rising .The content of amylum decreased .The content of rough fat decreased gradually and the decrease of rough fat was apparent during the cold stratification .The changing trend of the activity of amylase was just the oppo-site of the change of the content of amylum .It showed a rising trend .The activity of peroxidase of every process of temperature-accelerated stratification rose significantly .Therefore,cold stratification was more advantageous to breaking the dormancy of Euscaphis konishii seeds and there was a high concordance between the change law of the contents of inner substances and the morphological post-maturation .