青藏高原东缘常见40种禾本科植物种子大小变异研究

The Seed Size Variation of 40 Graminious Species in the Eastern Qinghai-Tibet Plateau

采集青藏高原东缘常见禾本科植物的种子,测量并计算种子的长、宽、高、质量等9项形态学指标,将上述指标分别与海拔高度、种子质量和种子总体方差间进行相关性分析。结果表明:①种子的各表型性状均存在一定程度的变异,其中种子长/高的变异系数最高,而种子质量的变异系数最低,表明种子质量较稳定。②相关性分析表明种子的长与种子质量间有较强的相关性;海拔高度与禾本科种子表型性状之间存在一定程度的相关性,沿海拔梯度,种子长、种子宽、种子高、种子宽/种子长和种子质量逐步减小;总体方差与种子长/种子高具有较高的相关性。认为可以用种子长/高替代总体方差来衡量禾本科种子的整体形态;海拔是影响禾本科种子大小及变异的一个重要因素。

The seeds of 40 gramineous species were collected from the alpine meadow in eastern Qinghai-Tibet Plateau.Based on the data of 9 morphological characteristics of seeds,the relativity among the morphological characteristics of seeds with altitude,variance and seed weight was analyzed.The results showed that： ①The seeds traits of 40 gramineous species exhibited certain differentiations in 9 morphological characteristics and the variation of coefficient of ratio of length to high of seed was the highest,while the coefficient of variation of seed weight was the lowest,indicating that seed weight was more stable than the others among the characteristics studied.②Correlation analyses suggested that there is significant linear correlation between the morphological variation of seeds and altitude,and there is significant linear correlation between seed length and seed weight.Variance considering three dimensions（length,breadth and high） of seeds have higher correlation to SL/SH.SL/SH instead of the variance considering three dimensions is more appropriate than the others to measure the seeds overall pattern of gramineous species;The altitude is an important factor affecting the seed size and its variation.