不同茎径甘蔗品种茎尖原生分生组织不同区域细胞分裂频率差异

Cell division frequency difference in various regions of stem tip protomeristem in sugarcane varieties with different stem diameters

关键词:  甘蔗  茎尖  原生分生组织  细胞分裂频率  茎径  株高

Key words:  sugarcane  stem tip  protomeristem  cell division frequency  stem diameter  stem length

摘要:

为探明甘蔗茎尖原生分生组织不同区域细胞分裂频率差异及其与茎径和株高的关系，对6个不同茎径品种5个不同生长时期的甘蔗茎尖进行石蜡连续纵切片显微观察，发现甘蔗茎尖原生分生组织各区域细胞分裂频率有明显差异：周缘分生区细胞(3.89%)＞原体原始细胞区(2.67%)＞髓分生区（1.46%）＞原套原始细胞区(1.30%)，以上差异均达到显著水平；各区域细胞分裂频率与甘蔗茎径均呈正相关，其中髓分生区和原套原始细胞区细胞分裂频率与茎径的相关系数较大，分别为r2=0.856*、r2=0.925*；各区域细胞分裂频率与甘蔗株高均呈负相关，其中原体原始细胞区细胞分裂频率与株高相关系数r2= 0.728*。结果表明对原生分生组织各区域细胞分裂频率的精确量化，可以揭示甘蔗茎尖原生分生组织各区细胞与其特征的内在联系和不同区域细胞活动能力差异是甘蔗茎增粗的细胞学基础。

Abstract:

In order to understand the correlation between difference of cell division frequency in various regions of stem tip protomeristem and stem diameter as well as plant height，continuous paraffin sections of six sugarcane varieties were investigated by microscopy at five different growth stages. The results showed that there was significant difference in cell division frequency of various regions of stem tip protomeristem. The difference followed the pattern:peripheral meristem(3.89%)＞corpus primary cell(2.67%)＞pith(1.46%)＞tunica primary(1.3%). There was positive correlation between cell division frequency in different regions of stem tip protomeristem and sugarcane stem diameter，and the correlation coefficients were highly significant between stem diameter and pith zone and tunica primary cell zone(r2=0.856*and r2=0.925*，respectively). However，there were negative correlations between stem length and cell division frequency of stem tip protomeristem in different zones，and the correlation coefficient between corpus primary cell and stem length was significant. The results could reveal the inherent relation between different stem tip protomeristem zones and their characteristics with precise quantifications of cell division frequency in different protomeristem zones of sugarcane. The difference of cell activity in different zones could be the basic cytology of sugarcane stem thickening.