CO_2倍增对紫花苜蓿叶片形态结构的影响

Effects of Doubled CO_2 on the Leaf Morphology and Structure of Alfalfa

应用光镜和扫描电镜研究了 Ｃ Ｏ２ 浓度倍增对紫花苜蓿（ Ｍｅｄｉｃａｇｏ ｓａｔｉｖａ） 叶片形态和结构特征的影响。结果表明，随着 Ｃ Ｏ２ 浓度升高，叶面积显著增加，气孔密度和气孔开度呈下降趋势。此外，还发现叶肉组织细胞层数增加，从而使叶片增厚。

The effects of doubled CO 2 on the morphological and anatomical characters of alfalfa (Medicago sativa) leaf were investigated by means of Light microscopy and SEM. Results showed that alfalfa grown at doubled CO 2, compared with that grown at ambient air, its leaflet area increased by 28.0%,stomatal density decreased by 18.35% at adaxial surface and 28.64% at abaxial surface because of the enlargement of epidermal cells at elevated CO 2 concentration, the maximum stomatal aperture also decreased by 10%. Furthermore, leaf thickness increased significantly due largely to the origin of an extral layer of mesphyll tissue in doubled CO 2.