40种常见药用草本植物根系解剖特征研究

Root Anatomical Traits of 40 Medicinal Herbs

摘要:

植物的根系具有水分吸收和运输的功能，部分还有重要的药用价值。该研究观察了40种药用草本植物粗根的解剖特征，比较了不同功能类群的差异性并分析了性状的相关性，同时结合系统发育和自然分布区气候因子解释了根系性状的种间变异性。结果表明，草本植物根系解剖特征种间差异显著；与双子叶植物相比，单子叶植物的根皮层占比更高，而中柱占比更小，揭示了两者根系吸收和运输策略的差异性。性状网络分析表明，木质部面积占比具有高的度和紧密度，是其中的中心性状，木质部面积占比与韧皮部面积占比正相关但与皮层占比负相关。除导管频度和皮层占比外，其他特征均未显示出显著的系统发育信号，说明根系性状受系统发育的影响较少。在单子叶草本植物中，年平均降水量与皮层占比呈正相关；而在双子叶草本中，年平均气温与导管直径正相关。该研究进一步揭示了药用草本植物根系结构的多样性和适应性。

Abstract:

The roots of plants have the function of water absorption and transport, and some of them also have important medical value. The anatomical characteristics of coarse roots of 40 medicinal herbs were observed, the differences among functional groups were compared, the correlations of traits were analyzed, and the interspecific variability of root traits was explained in combination with phylogenetic and natural climate factors. The results showed that the root anatomical characteristics of herbaceous plants were significantly different among species. Compared with dicotyledonous plants, the proportion of root cortex in monocotyledonous plants was higher, while the proportion of median column was smaller, which revealed the differences in root absorption and transport strategies between the two plants. Traits network analysis showed that xylem area ratio (XAR) was the central trait with the highest degree and tightness. XAR was positively correlated with phloem area ratio but negatively correlated with cortex fraction (CF). Except for vessel frequency and CF, other traits showed no significant phylogenetic signals, indicating that root characters were less affected by phylogeny. In monocotyledon herbaceous species, mean annual precipitation was positively correlated with CF, while in dicotyledon herbaceous species, mean annual temperature was positively correlated with average vessel diameter. These would further reveal the diversity and adaptability of the root structure of medicinal herbs.