不同谷子品种叶片表皮微形态学特征

为了解谷子叶片表皮微形态学特征,利用扫描电镜对3个谷子品种叶片表皮微形态结构进行观察。结果表明:谷子叶片表皮主要由表皮细胞、气孔器、乳突和表皮毛等结构组成;下表皮表皮毛分布浓密,气孔大小、气孔密度、单位面积内气孔总面积均大于上表皮。豫谷1号、豫谷18和冀谷19下表皮气孔周长分别比上表皮长9.77%、20.51%和24.36%,单个气孔面积分别是上表皮的1.22、1.58和1.34倍,气孔密度分别比上表皮高4.79%、37.60%和4.56%,单位面积内气孔总面积分别是上表皮的1.31、2.23和1.52倍。品种间比较,豫谷18叶片上下表皮表皮毛分布最为密集,气孔密度最大(上表皮221.84个/mm₂,下表皮305.25个/mm₂),气孔较小(上下表皮单个气孔面积分别为262.49、414.13 m₂),单位面积内气孔总面积最大(174162.13?滋m₂/mm₂)。由此可见,品种间叶片表皮微形态结构的差异性可为揭示品种高产及抗性机理提供形态学依据。

Comparative Study of Micromorphological Characteristics of the Leaf Epidermis of Different Foxtail Millet Varieties

In order to determine the micromorphological characteristics of the leaf epidermis of foxtail millet,the three foxtail millet varieties Yugu1,Yugu No.18,and Jigu 19 were studied by using scanning electron microscopes to observe their leaf epidermis structure.The results showed that their leaf epidermis is made up of epidermal cells,stomata,papillae,epidermal hairs and so on.The lower epidermis has denser epidermal hairs,larger stomatal size,higher stomatal density,and larger total stomatal area per unit area than the upper epidermis.In Yugu No.1,Yugu 18,and Jigu19,the stomatal perimeter of the lower epidermis is larger than that of the upper epidermis by 9.77%,20.51%,and 24.36%,respectively;the single stomatal area of the lower epidermis is 1.22,1.58,and 1.34 times that of the upper epidermis,respectively;the stomatal density of the lower epidermis is larger than that of the upper epidermis by 4.79%,37.60%,and 4.56%,respectively;the total stomatal area per unit area of the lower epidermis is 1.31,2.23,and 1.52 times that of the upper epidermis,respectively.Of the three varieties,Yugu 18 has the densest epidermal hairs on the upper and lower epidermis and the largest stomatal density(the stomatal densities of the upper and lower epidermis are 221.84 No./mm₂ and 305.25 No./mm₂,respectively),smaller stomatal size(single stomatal areas of the upper and the lower epidermis are 262.49 m₂ and 414.13 m₂,respectively),and the largest total stomatal area per unit area(174162.13μm₂/mm₂).Such micromorphological features of the leaf epidermis of Yugu 18 are consistent with its high-yielding ability and strong tolerance to stresses.Therefore,the differences in micromorphological features of leaf epidermis structure among various millet varieties provide an insight into the mechanisms of the high-yielding capacity and stress tolerance of some foxtail millet varieties.