---

作 者 ：马 跃，张 蕾，李元源，东中东，张志宏*

期 刊 ：西北植物学报 2012年 3期 页码：477~483

关键词：苹果；二倍体；同源四倍体；电镜扫描；石蜡切片；叶绿素荧光参数；

Keywords:apple, diploid, autotetraploid, scanning electron microscopy, paraffin section, chlorophyll fluorescence paramet,

摘 要 ：采用扫描电镜和石蜡切片法，以‘寒富’苹果二倍体及经秋水仙素加倍获得的同源四倍体植株为材料，比较两种倍性植株叶片超微结构、叶绿素含量及叶绿素荧光参数的日变化规律。结果显示：（1）与二倍体植株相比较，其同源四倍体叶片厚度、栅海比、气孔长、气孔宽、分别增加了15.1%、16.1%、70.5%、27.2%，而气孔密度显著减少了58.7%；其同源四倍体叶保卫细胞中叶绿体数和叶绿素含量分别比二倍体植株高出125.3%、37.7%。（2）‘寒富’苹果同源四倍体与其二倍体的叶绿素荧光参数PSⅡ的原初光能转化效率（F_v/F_m）、PSⅡ的潜在光化学效率（F_v/F₀）和以吸收光能为基础的光合性能指数（PI）值的日变化趋势相似，但PI平均值比二倍体显著高出38.6%。研究表明，同源四倍体较二倍体叶片在形态上更大、更厚，气孔更大、密度更小，栅海比更大，表现出抗病的叶片结构；同时同源四倍体较二倍体含有更高的叶绿素含量，表现更优良的光合特性。

Abstract:The study plant was autotetraploid ‘Han Fu’ apple,which was doubled by colchicin from a diploid.The leaves of autotetraploid and diploid plants were compared by using the methods of paraffin section,scanning electron microscopy(SEM) and chlorophyll fluorescence parameters diurnal fluctuations.The results showed that:(1)The thickness of leaf,the P/S,the length of stoma,the width of stoma,the number of chloroplasts per guard cell pair and the content of chlorophyll of autotetraploid were increased by 15.1%,16.1%,70.5%,27.2%,125.3% and 37.7%,but the density of stomata was decreased by 58.7% than that of diploid.The different was significant.The variation tendency of F_v/F_m,F_v/F₀ and PI value were similar.The average performance index (PI) value in autotetraploid apple was increased by 38.6% than that of diploid.So,the leaves of autotetraploid were more big,more thick.The stomata were more bigger and the stoma density was more smaller.It suggested the autotetraploid had better disease resistance and photosynthetic performance than that of diploid.

---