Abstract:

To investigate the adaptation mechanism to alpine environment, the stomatal characteristics of Ligularia virgaurea in Tibetan Plateau were observed and the ways they responded to environmental variables were researched. The results showed that stomata were distributed randomly on both upper and lower epidermis and the stomatal apparatus was anomocytic type. Besides, stomata density and stomata index were relatively high. Geographic variations and eight temperature factors had significant effect on stomata length of leaf epidermis(P<0.01). And ABT, MTWM, MTGS and WI only had relationship with stomata index of upper epidermis (0.01 < P < 0.05). Precipitation variables influenced stomata density and stomata index of upper epidermis and there were no significant effects on stomata density and stomata index of lower epidermis and stomata length. Overall, the morphological characteristics of the stomata showed an adaptive relationship with the extreme surroundings.

Key words: Ligularia virgaurea, Leaf epidermis, Stomata, Features, Environmental response, Tibetan Plateau

摘要：

为探讨黄帚橐吾（Ligularia virgaurea）对高寒环境的适应机制，对青藏高原的优势物种黄帚橐吾的叶表皮气孔特征进行观察，分析其对气候生态因子的响应。结果表明：黄帚橐吾叶片上、下表皮均分布有气孔，气孔分布无规律，随机散生排列，气孔器为无规则型，气孔密度与气孔指数相对较高。地理分异变量对黄帚橐吾叶表皮气孔长度的效应极其显著（P<0.01）。8个温度因子对黄帚橐吾叶片上、下表皮气孔长度效应极其显著（P<0.01），ABT（年生物温度）、MTWM（最热月温）、MTGS（生长季温度）与WI（温暖指数）对上表皮气孔指数效应显著（0.01 < P < 0.05）；水分因子会影响黄帚橐吾叶片上表皮的气孔密度与气孔指数，而对下表皮气孔密度、气孔指数以及上、下表皮气孔长度无影响。黄帚橐吾叶表皮气孔特征在形态、数量及与环境关系的这些特点，反映了其对高寒极端环境的适应。

关键词: 黄帚橐吾, 叶表皮, 气孔, 特征, 环境响应, 青藏高原