盾叶薯蓣四倍体与二倍体叶表皮及气孔器显微结构的比较

Comparison on microstructures of epidermis and stomatal apparatus of leaf between tetraploid and diploid of Dioscorea zingiberensis

关键词:  盾叶薯蓣  二倍体  四倍体  表皮  气孔器  保卫细胞  显微结构

Key words:  Dioscorea zingiberensis  diploid  tetraploid  epidermis  stomatal apparatus  guard cell  microstructure

摘要:

对盾叶薯蓣四倍体和二倍体阴叶和阳叶表皮及气孔器的显微形态结构进行了比较。结果显示:叶片表皮细胞及气孔器的形态结构因染色体倍性及光照的不同而存在明显差异。表皮细胞有规则多边形与不规则细胞壁内褶2种类型; 气孔器为典型的双子叶植物无规则型气孔器,仅分布在下表皮。四倍体表皮细胞密度、气孔器密度及气孔指数平均值分别为476.28±6.87个·mm^-2、78.22±3.1个·mm^-2、14.11,较二倍体的分别小4.60%、17.95%和11.98%。前者气孔器长、宽及保卫细胞宽度平均值分别为32.78±2.09 μm、26.07±1.55 μm、9.63±1.14 μm,较后者的分别大10.73%、3.90%和18.01%,差异极显著。前者阴叶的较其阳叶的分别大5.77%、6.00%、8.72%; 后者的则分别大1.72%、1.74%、2.41%。前者叶片保卫细胞中的叶绿体数目为23.93±3.19个,较后者的多74.00%。表皮细胞及气孔器密度、气孔指数,气孔器大小,保卫细胞叶绿体数目、尤其是保卫细胞宽度,可作为倍性鉴定的参考依据。四倍体高产有其良好的叶片结构基础。

Abstract:

Morphology and microstructure of epidermis and stomatal apparatus in guard cell of sunny leaves and shady ones between diploid and tetraploid Dioscorea zingiberensis have been comparatively studied. The results are as follows:there are distinctly differences on their morphology and microstructure between diploid and tetraploid,sunny leaf and shady one. There are two morphological types of epidermal cells: regular polygon epidermis and irregular meander configuration ones. The stomatal apparatus,which exist only in under epidermis,is irregular type of stomatal apparatus as that of typical dicotyle. The mean densities of epidermic cells and stomatal apparatus,stomatal index of tetraploid,which are 476.82±6.87 cells·mm^-2,78.22±3.1 units·mm^-2 and 14.11 respectively,is smaller by 4.60%,17.95% and 11.98% respectively than that of diploid. But the even length and width of stomatal apparatus,width of guard cell of the former,which are 32.78±2.09μm,26.07±1.55μm,9.63±1.14μm respectively,is larger by 10.73%,3.90% and 18.01% than that of the latter respectively,and the difference is all at extremely distinct level. That of shady leaf of the former is larger by 5.77%,6.00% and 8.72% respectively than that of sunny one,and the latter by 1.72%,1.74% and 2.41% respectively. The chloroplast numbers in guard cell of stoma of tetraploid are 23.93±3.19,74.00% more than that of diploid. The densities of epidermic cell and stoma,stomatal index,size of stoma,chloroplast numbers in guard cell,especially the width of guard cell can be used to identify the tetraploid and diploid. The leaf structure of tetraploid is good for high yield.