黄山花楸种子休眠解除技术及其解剖学观察

Dormancy breaking techniques and anatomy mechanism of seed of Sorbus amabilis

采用赤霉素、浓硫酸、氢氧化钠、低温层积、机械划伤种皮等处理方法进行解除黄山花楸种子休眠试验,并对种子休眠解除过程中超微结构变化进行电镜观察与分析。结果表明：种皮划伤处理和低温层积75~90 d种子萌发率均可达90%以上,是打破黄山花楸种子休眠的有效途径;赤霉素浸种后低温层积处理也可打破种子休眠,但赤霉素各种浓度处理效果均不如直接层积的处理效果;其他处理未能解除黄山花楸种子休眠。层积处理过程中种子表皮扫描电镜和子叶细胞透射电镜观察显示,黄山花楸种子萌发率和休眠解除效果与种皮角质层破裂解体、子叶细胞结构变化及储藏物质降解程度密切相关。

Dormancy breaking techniques and ultra-structural changes were studied in seeds of Sorbus amabilis Cheng ex Yü.Seeds were under different treatments including various levels of GA3,NaOH,H2SO4,cold stratification and mechanical scarification.The results showed that 90 % of the seeds of S.amabilis germinated by mechanical scarification and cold stratification for a period of 75—90 days,which are effective methods to break dormancy.GA3＋cold stratification can also break seed dormancy,but less effective than treated with directly cold stratification.Other treatments could not break seed dormancy.Micro-structural characters of seed surface and cotyledon cells were observed under scanning and transmission electron microscope in different period of cold stratification,the results showed that germination rate and dormancy breaking effects are directly related to the degree of cuticles broken and disintegration on seed surfaces,and directly related to structural changes and deposition degrade in cotyledon cells.